Co-reporter:Ning Lin, Tianjun Xu, Tieqiang Li, Ying Han, and Yitai Qian
ACS Applied Materials & Interfaces November 15, 2017 Volume 9(Issue 45) pp:39318-39318
Publication Date(Web):October 23, 2017
DOI:10.1021/acsami.7b10639
Si-containing graphite-based composites are considered as promising high-capacity anodes for lithium-ion batteries (LIBs). Here, a controllable and scalable self-assembly strategy is developed to produce micro-nanostructured graphite/Si/reduced graphene oxides composite (SGG). The self-assembly procedure is realized by the hydrogen bond interaction between acylamino-modified graphite and graphene oxides (GO); Si nanoparticles are in situ embedded between graphite and GO sheets uniformly. This architecture is able to overcome the incompatibility between Si nanoparticles and microsized graphite. Accordingly, the as-prepared SGG anode (Si 8 wt %) delivers a reversible Li-storage capacity of 572 mAh g–1 at 0.2 C, 502.2 mAh g–1 after 600 cycles at 0.8 C with a retention of 92%, and a capacity retention of 64% even at 10 C. The impressive electrochemical properties are ascribed to the stable architecture and three-dimensional conductive network constructed by graphite and graphene sheets, which can accommodate the huge volume change of Si, keep the conductive contact and structural integrity, and suppress side reactions with electrolyte. Additionally, the full-cell (LiFePO4 cathode/SGG anode) delivers a specific capacity of 550 mAh g–1 with a working potential beyond 3.0 V.Keywords: graphene; graphite; Li-ion batteries; self-assembly; Si;
Co-reporter:Lei Hu, Yue Lu, Tianwen Zhang, Tao Huang, Yongchun Zhu, and Yitai Qian
ACS Applied Materials & Interfaces April 26, 2017 Volume 9(Issue 16) pp:13813-13813
Publication Date(Web):April 7, 2017
DOI:10.1021/acsami.7b01387
We report an activation-free approach for fabricating ultramicroporous carbon as an accommodation of sulfur molecules for Li–S and Na–S batteries applications in carbonate-based electrolyte. Because of the high specific surface area of 967 m2 g–1, as well as 51.8% of the pore volume is contributed by ultramicropore with pore size less than 0.7 nm, sulfur cathode exhibits superior electrochemical behavior in carbonate-based electrolyte with a capacity of 507.9 mA h g–1 after 500 cycles at 2 C in Li–S batteries and 392 mA h g–1 after 200 cycles at 1 C in Na–S batteries, respectively.Keywords: activation-free approach; carbonate-based electrolyte; lithium−sulfur batteries; metal−sulfur batteries; sodium−sulfur batteries; ultramicroporous carbon;
Co-reporter:Qianqian Yang;Jie Zhou;Genqiang Zhang;Cong Guo;Meng Li;Yongchun Zhu
Journal of Materials Chemistry A 2017 vol. 5(Issue 24) pp:12144-12148
Publication Date(Web):2017/06/20
DOI:10.1039/C7TA03060F
Sb nanoparticles encapsulated in 1-D N-doped porous carbon (denoted as Sb/NPC) have been fabricated by an in situ nanoconfined replacement reaction between SbCl3 and the intermediate Ni/NPC, in which Ni/NPC was obtained by annealing the hydrothermally synthesized nickel–nitrilotriacetic acid (Ni–NTA) precursor in an argon atmosphere. The Sb nanoparticles with a size of 10–20 nm were uniformly encapsulated in the 1-D N-doped porous carbon scaffolds. When the Sb/NPC composite was applied as an anode material in the batteries, it exhibited a high reversible capacity of 556 mA h g−1 at 200 mA g−1 after 100 cycles for Li-ion batteries (LIBs) and a reversible capacity of 400.9 mA h g−1 at 100 mA g−1 after 100 cycles for Na-ion batteries (NIBs). Such enhanced electrochemical performance of the designed Sb/NPC can be attributed to the synergistic effect between uniformly dispersed Sb nanoparticles and the 1-D N-doped porous carbon matrices.
Co-reporter:Zhiguo Hou;Xueqian Zhang;Xiaona Li;Yongchun Zhu;Jianwen Liang
Journal of Materials Chemistry A 2017 vol. 5(Issue 2) pp:730-738
Publication Date(Web):2017/01/03
DOI:10.1039/C6TA08736A
Aqueous rechargeable batteries have received significant attention because of their low-cost and security. However, the narrow electrochemical stability window (about 1.23 V) of the aqueous electrolyte sets a limit on their energy output. Herein, we have developed an aqueous rechargeable hybrid battery using Na2MnFe(CN)6 nanocubes as the cathode and a zinc metal sheet as the anode, which delivered a high energy density of 170 W h kg−1 and a capacity retention of 75% over 2000 cycles with an operating voltage of up to 2.0 V. By adding sodium dodecyl sulfate (SDS) to the aqueous electrolyte, the electrochemical stability window of the electrolyte was expanded to about 2.5 V. The results of the experiments and calculations based on the density functional theory indicate that SDS can not only inhibit the decomposition of water, suppress the dissolution of Mn and the corrosion of zinc but also increase the cycle life and rate capability. The low-cost, high energy density, and long cycle life of the battery suggest that it is a promising candidate for energy storage applications.
Co-reporter:Meng Li, Jianbin Zhou, Jie Zhou, Cong Guo, Ying Han, Yongchun Zhu, Gongming Wang, Yitai Qian
Materials Research Bulletin 2017 Volume 96, Part 4(Volume 96, Part 4) pp:
Publication Date(Web):1 December 2017
DOI:10.1016/j.materresbull.2017.05.016
•Ultrathin SnS2 nanosheets have large surface area and fast charge transfer properties.•Ultrathin SnS2 nanosheets can greatly improve the electrochemical properties of S/C composites for Li-S batteries.•Superior electrochemical performance of S/C-SnS2-10 composites can be ascribed to the optimized synergistic effects between SnS2 and porous carbon.Ultrathin SnS2 nanosheets modified sulfur/carbon (S/C-SnS2) composites were synthesized through a facile method by mixing sublimed sulfur, Ketjen Black and ultrathin SnS2 nanosheets. The ultrathin SnS2 nanosheets can provide remarkable binding strength, large surface area and fast charge transfer, therefore leading to favorable chemical interaction with polysulfides in Li-S batteries. Accompanied with the synergistic effects between physical confinement of porous carbon and chemical interactions of SnS2, S/C-SnS2 composites with different mass ratio of ultrathin SnS2 nanosheets and C show much improved electrochemical properties. Among them, S/C-SnS2 composite with 10 wt% of ultrathin SnS2 nanosheets and 75 wt% of sulfur maintains superior long term cycling capacities of 800 mAh g−1 at 0.5 C after 300 cycles and 540 mAh g−1 at 2 C after 700 cycles.Download high-res image (123KB)Download full-size image
Co-reporter:Jun Pan;Nana Wang;Yanli Zhou;Xianfeng Yang;Wenyao Zhou
Nano Research 2017 Volume 10( Issue 5) pp:1794-1803
Publication Date(Web):04 March 2017
DOI:10.1007/s12274-017-1501-y
High-capacity anode materials are highly desirable for sodium ion batteries. Here, a porous Sb/Sb2O3 nanocomposite is successfully synthesized by the mild oxidization of Sb nanocrystals in air. In the composite, Sb contributes good conductivity and Sb2O3 improves cycling stability, particularly within the voltage window of 0.02–1.5 V. It remains at a reversible capacity of 540 mAh·g–1 after 180 cycles at 0.66 A·g–1. Even at 10 A·g–1, the reversible capacity is still preserved at 412 mAh·g–1, equivalent to 71.6% of that at 0.066 A·g–1. These results are much better than Sb nanocrystals with a similar size and structure. Expanding the voltage window to 0.02–2.5 V includes the conversion reaction between Sb2O3 and Sb into the discharge/charge profiles. This would induce a large volume change and high structure strain/stress, deteriorating the cycling stability. The identification of a proper voltage window for Sb/Sb2O3 paves the way for its development in sodium ion batteries.
Co-reporter:Xueqian Zhang, Zhiguo Hou, Xiaona Li, Jianwen Liang, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2016 vol. 4(Issue 3) pp:856-860
Publication Date(Web):27 Nov 2015
DOI:10.1039/C5TA08857G
Layer structure Na-birnessite (Na-Bir) Na0.58MnO2·0.48H2O has been synthesized through a precipitation reaction at room temperature and used as a rechargeable aqueous sodium-ion battery (RASIB) cathode material for the first time. As a RASIB cathode material, the layered Na-birnessite manifests a high specific capacity of 80 mA h g−1 at 1C without obvious capacity loss after 150 cycles. After heat treatment of the Na-Bir sample, it can deliver a specific capacity of 79 mA h g−1 at 1C but only retains 60% of the initial capacity after 150 cycles. The XRD analysis of the Na-Bir sample after 150 cycles reveals that the layer structure is retained, while inductively coupled plasma atomic emission spectroscopy (ICP-AES) indicates that the dissolution of Mn is merely 0.008 wt% of Na-Bir after 150 cycles. As a cathode electrode in full batteries coupled with a NaTi2(PO4)3 anode electrode, a high capacity of 39 mA h g−1 at 10C is obtained with a capacity retention of 94% after 1000 cycles.
Co-reporter:Jianbin Zhou, Yang Lan, Kailong Zhang, Guoliang Xia, Jin Du, Yongchun Zhu and Yitai Qian
Nanoscale 2016 vol. 8(Issue 9) pp:4903-4907
Publication Date(Web):05 Feb 2016
DOI:10.1039/C5NR08961A
The composites of carbon nanotube wrapped Si particles (CNTWS) were synthesized in situ by using the catalytic chemical vapor deposition (CCVD) method. In this process, carbon nanotubes were produced in situ to wrap Si by the catalysis action of nascent Cu* under an acetylene atmosphere at a relatively low temperature of 400 °C, in which nascent Cu* was created by the reaction between Si particles and CuCl synchronously. The weight ratio of Si/C in CNTWS is 0.76/0.24. As anode materials for lithium ion batteries, the CNTWS composites exhibit a reversible discharge capacity of 1031.1 mA h g−1 at 1.8 A g−1 after 500 cycles, and 868.2 mA h g−1 at 10.0 A g−1. The high electrochemical performance of CNTWS composites is associated with the in situ formed carbon nanotubes.
Co-reporter:Kailong Zhang, Yanhua Xu, Yue Lu, Yongchun Zhu, Yuying Qian, Danfeng Wang, Jianbin Zhou, Ning Lin and Yitai Qian
Journal of Materials Chemistry A 2016 vol. 4(Issue 17) pp:6404-6410
Publication Date(Web):22 Mar 2016
DOI:10.1039/C6TA01118G
Composites of the graphene oxide-wrapped bipyramidal sulfur@polyaniline core–shell structure (S@PANI/GO) have been prepared at low temperature. The FT-IR and Raman spectra illustrated the chemical effect between PANI and GO, and the SEM images illustrated the tight connection with each other. As a cathode for Li–S batteries, the S@PANI/GO composite demonstrated better electrochemical performance than S@PANI, or S/GO composites. The S@PANI/GO composite delivered enhanced cycle stability (0.2 C, 875 mA h g−1 after 100 cycles) and high-rate capability (4 C, 466 mA h g−1). Even at 1 C, the S@PANI/GO composite still delivered a capacity of 641 mA h g−1 after 300 cycles. The enhanced performance should benefit from the core–shell structure with a synergistic effect between polyaniline and graphene oxide.
Co-reporter:Xiaona Li, Yue Lu, Zhiguo Hou, Wanqun Zhang, Yongchun Zhu, and Yitai Qian , Jianwen Liang and Yitai Qian
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 30) pp:19550-19557
Publication Date(Web):July 15, 2016
DOI:10.1021/acsami.6b06565
The common sulfur/carbon (S/C) composite cathodes in lithium sulfur batteries suffer gradual capacity fading over long-term cycling incurred by the poor physical confinement of sulfur in a nonpolar carbon host. In this work, these issues are significantly relieved by introducing polar SnO2 or SnS2 species into the S/C composite. SnO2- or SnS2-stabilized sulfur in porous carbon composites (SnO2/S/C and SnS2/S/C) have been obtained through a baked-in-salt or sealed-in-vessel approach at 245 °C, starting from metallic tin (mp 231.89 °C), excess sulfur, and porous carbon. Both of the in situ-formed SnO2 and SnS2 in the two composites could ensure chemical interaction with lithium polysulfide (LiPS) intermediates proven by theoretical calculation. Compared to SnO2/S/C, the SnS2/S/C sample affords a more appropriate binding effect and shows lower charge transfer resistance, which is important for the efficient redox reaction of the adsorbed LiPS intermediates during cycling. When used as cathodes for Li–S batteries, the SnS2/S/C composite with sulfur loading of 78 wt % exhibits superior electrochemical performance. It delivers reversible capacities of 780 mAh g–1 after 300 cycles at 0.5 C. When further coupled with a Ge/C anode, the full cell also shows good cycling stability and efficiency.Keywords: chemical interaction; energy storage; lithium sulfur batteries; tin dioxide; tin disulfide;
Co-reporter:Wenlong Cai, Jianbin Zhou, Gaoran Li, Kailong Zhang, Xianyu Liu, Can Wang, Heng Zhou, Yongchun Zhu, and Yitai Qian
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 41) pp:27679
Publication Date(Web):October 3, 2016
DOI:10.1021/acsami.6b08852
B,N-Co-doped graphene supported sulfur (S@BNG) composite is synthesized by using melamine diborate as precursor. XPS spectra illustrates that BNG with a high percentage and dispersive B, N (B = 13.47%, N = 9.17%) and abundant pyridinic-N and N–B/N═B bond, show strong interaction with Li2Sx proved by adsorption simulation experiments. As cathode for Li–S half cell, S@BNG with a sulfur content of 75% displays a reversible capacity of 765 mA h g–1 at 1 C even after 500 cycles (a low fading rate of 0.027% per cycle). Even at a high sulfur loading of 4.73 mg cm–2, S@BNG still shows a high and stable areal capacity of 3.5 mA h cm–2 after 48 cycles. When S@BNG composite as cathode combines with high performance lithiated Ge anode (discharge capacity of 1138 mA h g–1 over 1000 cycles at 1 C in half cell), the assembled Ge–S full battery exhibits a superior capacity of 530 mA h g–1 over 500 cycles at the rate of 1 C.Keywords: B; Ge−S full battery; high content of heteroatoms; N-co-doped graphene; nano Ge; strong chemisorption
Co-reporter:Ying Han, Ning Lin, Yuying Qian, Jianbin Zhou, Jie Tian, Yongchun Zhu and Yitai Qian
Chemical Communications 2016 vol. 52(Issue 19) pp:3813-3816
Publication Date(Web):04 Feb 2016
DOI:10.1039/C6CC00253F
N-doped Si nanoparticles were prepared synchronously by nitridation of Mg2Si. The existence of nitrogen doping can be demonstrated by the XPS spectrum and EELS energy-filtered images. When the N-doped Si nanoparticles were used as an anode for Li-ion batteries, a high reversible capacity of 2595 mA h g−1 at 0.36 A g−1 after 40 cycles, and 805 mA h g−1 at 3.6 A g−1 after 800 cycles could be obtained.
Co-reporter:Xiaona Li, Jianwen Liang, Yue Lu, Zhiguo Hou, Wanqun Zhang, Yongchun Zhu, Yitai Qian
Journal of Power Sources 2016 Volume 329() pp:379-386
Publication Date(Web):15 October 2016
DOI:10.1016/j.jpowsour.2016.08.101
•A synchronous approach for S/Bi2S3/C composite cathodes is described.•The in-situ formed Bi2S3 could provide anchoring effect with lithium polysulfides.•Those S/Bi2S3/C composites exhibit good performance in LiS batteries.S/Bi2S3/C composites have been prepared based on melt strategy at 280 °C starting from metallic bismuth (mp 271.3 °C), excess sulfur powder and porous carbon with different ratio. In the as-prepared composites, the in-situ formed Bi2S3 in molten S environment can homogeneously dispersed in S and carbon. Combining the physical confinement of porous carbon and chemical interaction of the in-situ formed Bi2S3, the dissolution of polysulfides has been well inhibited. Thus, the obtained S/Bi2S3/C composite exhibits good electrochemical performance, which could deliver capacity of ∼825 mAh g−1 at 0.5 C over 400 cycles, with 91% capacity retention and high Coulombic efficiency.
Co-reporter:Jie Zhou, Ning Lin, Wen long Cai, Cong Guo, Kailong Zhang, Jianbin Zhou, Yongchun Zhu, Yitai Qian
Electrochimica Acta 2016 Volume 218() pp:243-251
Publication Date(Web):10 November 2016
DOI:10.1016/j.electacta.2016.09.130
•S/CoS2 Nanoparticles-Embedded N-doped Carbon Polyhedrons are prepared.•The composites deliver the enhanced cycling stability in lithium-sulfur battery.•The enhanced electrochemical performance is mainly due to the synergistic effects of N-doped carbon polyhedrons and embedded CoS2.S/CoS2 nanoparticles-embedded N-doped carbon polyhedrons (S/CoS2-NC) as the cathode of lithium-sulfur battery are prepared. The synthesis is via the carbonization of metal organic frameworks polyhedron ZIF-67, followed by the heat treatment with sulfur. XRD confirms the existence of CoS2 and S, TEM shows the polyhedrons morphology and EDX mapping analysis displays the uniform distribution of Co, S and N in the carbon polyhedrons. As cathode for lithium-sulfur battery, S/CoS2-NC exhibit the enhanced cycling stability with the capacity of 702 mA h g−1 at 0.5C after 250 cycles and rate performance, which is superior to S/Co nanoparticles-embedded N-doped carbon polyhedrons composites (S/Co-NC), S/N-doped carbon polyhedrons composites (S-NC) and the bare sulfur. When coupled with the Ge anode, the discharge capacity of 502 mA h g−1 is obtained after 75 cycles at 0.5C. The enhanced property is mainly attributed to the synergistic effects of N-doped carbon polyhedrons and embedded CoS2.
Co-reporter:Yanhua Xu, Jianwen Liang, Kailong Zhang, Yongchun Zhu, Denghu Wei, Yitai Qian
Electrochemistry Communications 2016 Volume 65() pp:44-47
Publication Date(Web):April 2016
DOI:10.1016/j.elecom.2016.02.009
•Mesoporous nanospheres consisting of ZnSe@C core-shell nanoparticles are prepared.•This composite delivers a high reversible 960 mA h g− 1 at 0.2 A g− 1 after 400 cycles.•The Se element is firstly proved to be generated and activated during the charging processes.Metal sulfides/selenides (MSx/MSex) are used as promising alternative electrode materials for Li-ion batteries. However, the performance of MSx/MSex electrodes is often accompanied by rising and additional reversible capacities beyond their theoretical capacities during cycling, the mechanisms of which are still poorly understood. This study employs ex situ X-ray photoelectron spectroscopy, along with cyclic voltammetry to control the electrochemical charge/discharge process, to explore the origin of the additional capacities in ZnSe@C composite electrodes. Such ZnSe@C composites exhibit a rising reversible capacity of 960 mAh g− 1 (approximately 2 times its theoretical capacity) at 0.2 A g− 1 after 400 cycles at 0.01–3 V. The analysis shows that a major contribution to the extra rising capacity in this system is due to the generation and activation of Se during the electrochemical process.The mesoporous ZnSe@C nanospheres exhibit a high rising reversible capacity. The major contribution to this extra rising capacity in this system is due to the generation and activation of Se during the electrochemical charging process.
Co-reporter:Xueqian Zhang, Zhiguo Hou, Xiaona Li, Jianwen Liang, Yongchun Zhu, Yitai Qian
Electrochimica Acta 2016 Volume 213() pp:416-422
Publication Date(Web):20 September 2016
DOI:10.1016/j.electacta.2016.07.134
Uniform MoO2 nanoparticles were synthesized and evaluated as intercalation-type lithium anode material within the potential window of 1.0–2.5 V. A remarkable high capacity of 226 mA h g−1 at 0.1 C and ultra-long cycle life of 7000 cycles at 5 C with capacity retention of 135 mA h g−1 (96% of initial capacity) have been achieved, which is comparable than that of commercial Li4Ti5O12 anode but with higher capacity. Furthermore, a full cell composed of MoO2 anode and LiCoO2 cathode was assembled exhibiting a high energy density of 179 Wh kg−1 (based on total mass of cathode and anode active material) and capacity retention of 169 mA h g−1 (87% of initial capacity) after 500 cycles at 1 C.
Co-reporter:Ning Lin, Tianjun Xu, Ying Han, Kangze Shen, Yongchun Zhu and Yitai Qian
RSC Advances 2016 vol. 6(Issue 83) pp:79890-79893
Publication Date(Web):17 Aug 2016
DOI:10.1039/C6RA16336J
The preparation of a porous Si@C nano-composite from Si-rich biomass such as bamboo leaves is realized through baking the precursor at 400 °C in air, followed by reduction in molten AlCl3 at 200 °C. During this process, both Si and C components in those natural precursors are recovered as active materials. The obtained crystallized Si nanoparticles are embedded well in the pyrolyzed porous carbon matrix. As an anode for Li-ion batteries, the Si@C nano-composite exhibits long-term cycling stability with a capacity of 600 mA h g−1 at 2.0 A g−1 after 3700 cycles.
Co-reporter:Lei Hu, Tianwen Zhang, Jianwen Liang, Yongchun Zhu, Kailong Zhang and Yitai Qian
RSC Advances 2016 vol. 6(Issue 1) pp:456-463
Publication Date(Web):03 Dec 2015
DOI:10.1039/C5RA22373C
Various LiFePO4 micro/nanostructures have been solvothermally synthesized using FeSO4 and ethylene glycol (EG) as the reactant and reaction medium, respectively. The LiFePO4 micro/nanostructures including nanoflakes, stacked microsheets, micro-dumbbells and micro-spindles have been selectively fabricated and tuned via adjusting trace Fe3+ obtained from oxidation of the reactant. The content of mediated-Fe3+ in the EG system plays an important role in the formation of the micro/nanostructures as well as the change in the pH value. In this work, the content of mediated-Fe3+ in the precursor solution as a problem worthy of attention was put forward and the evolution process of the LiFePO4 micro/nanostructures has been extensively studied. Among these micro/nanostructures of LiFePO4, the LiFePO4 micro-dumbbells as a cathode material for lithium-ion batteries showed the most excellent electrochemical performance with a discharge capacity of 117 mA h g−1 at a high rate of 10C (1C = 169 mA h g−1), which demonstrates that the exposed crystal plane and morphology of LiFePO4 play critical roles in the electrochemical performance. This work not only provides deeper knowledge into the formation mechanism of LiFePO4 microstructures, but also paves a facile way to prepare scalable LiFePO4 with a high rate performance and high tap density.
Co-reporter:Danfeng Wang, Kailong Zhang, Yongchun Zhu, Yang Lan, Lei Hu, Ning Lin, Jianbin Zhou, Yitai Qian
Materials Letters 2016 Volume 175() pp:32-35
Publication Date(Web):15 July 2016
DOI:10.1016/j.matlet.2016.03.135
•A novel strategy is developed to wrap nanocrystals within GO.•The assembly process proceeds fast at room temperature.•The nanocrystals can be uniformly wrapped by GO sheets.•This method is widely applicable.•The prepared GO-wrapped SnSe composite exhibits good lithium storage performance.A novel strategy is developed to prepare graphene oxide-wrapped nanocrystals composite (GO@NCs) by the assistance of chitosan (CS). This assembly process can be accomplished at room temperature within two minutes, which is driven by both hydrogen bonding and electrostatic interaction between GO sheets and CS chains. It's also worth pointing out that this novel method can be widely applied in preparing various kinds of GO-wrapped nanocrystals composites, and the coated GO can further enhance the electrochemical performance of the GO@NCs composite. For instance, the GO-wrapped tin selenide nanorods composite (GO@SnSe) prepared by this method is evaluated as an anode for lithium ion batteries and delivers an enhanced reversible capacity of 764 mA h g−1 at the current density of 100 mA g−1 after 100 cycles, which is much higher than that of bare SnSe nanorods.A novel approach is developed to fabricate graphene oxide-wrapped nanocrystals composite (GO@NCs) at room temperature for much better lithium storage performance.
Co-reporter:Cong Guo, Qianqian Yang, Jianwen Liang, Lili Wang, Yongchun Zhu, Yitai Qian
Materials Letters 2016 Volume 184() pp:332-335
Publication Date(Web):1 December 2016
DOI:10.1016/j.matlet.2016.08.053
•Sn nanoparticles are uniformly dispersed in N-doped hollow carbon nanospheres.•SnO2 serves as both self-template and Sn source.•The Sn@NC structure makes for good lithium storage performances.Sn-contained N-doped carbon composite (Sn@NC) with Sn nanoparticles of 5–30 nm uniformly dispersed in N-doped hollow carbon nanosphere matrix was produced by in-situ polymerization of pyrrole, and reduction of SnO2 synchronous with decomposition of polypyrrole. SnO2 nanospheres serve as both the template of hollow carbon nanospheres and the Sn source. Due to the cooperation of the uniformly dispersed Sn particles and N-doped hollow carbon structure, the obtained Sn@NC shows a reversible capacity of 1070 mA h g−1 over 200 cycles at 0.2 C and 500 mA h g−1 over 500 cycles at 5 C.
Co-reporter:Jianwen Liang, Xiaona Li, Zhiguo Hou, Wanqun Zhang, Yongchun Zhu, and Yitai Qian
ACS Nano 2016 Volume 10(Issue 2) pp:2295
Publication Date(Web):January 20, 2016
DOI:10.1021/acsnano.5b06995
A deep reduction and partial oxidation strategy to convert low-cost SiO2 into mesoporous Si anode with the yield higher than 90% is provided. This strategy has advantage in efficient mesoporous silicon production and in situ formation of several nanometers SiO2 layer on the surface of silicon particles. Thus, the resulted silicon anode provides extremely high reversible capacity of 1772 mAh g–1, superior cycling stability with more than 873 mAh g–1 at 1.8 A g–1 after 1400 cycles (corresponding to the capacity decay rate of 0.035% per cycle), and good rate capability (∼710 mAh g–1 at 18A g–1). These promising results suggest that such strategy for mesoporous Si anode can be potentially commercialized for high energy Li-ion batteries.Keywords: general strategy; high stabilization; lithium ion batteries; mesoporous; silicon;
Co-reporter:Ning Lin, Ying Han, Jie Zhou, Kailong Zhang, Tianjun Xu, Yongchun Zhu and Yitai Qian
Energy & Environmental Science 2015 vol. 8(Issue 11) pp:3187-3191
Publication Date(Web):23 Sep 2015
DOI:10.1039/C5EE02487K
A low temperature molten salt process is developed to prepare crystalline Si nanoparticles through the reduction of micro-sized high silicon zeolite by metallic Al (or Mg) in molten AlCl3. The reaction can be initiated at 200 °C, and the yield is about 40%. As the reaction temperature increases to 250 °C, the yield can reach about 75%. When the prepared Si was used as an anode for Li-ion batteries, reversible capacities of 2663 mA h g−1 at 0.5 A g−1 after 50 cycles and 870 mA h g−1 at 3 A g−1 after 1000 cycles can be obtained. Similarly, this synthetic strategy is employed to synthesize Si nanoparticles starting from various abundant raw materials including SiO2 powder, kieselguhr, fiberglass, and even the natural mineral of albite.
Co-reporter:Xiaona Li, Jianwen Liang, Kailong Zhang, Zhiguo Hou, Wanqun Zhang, Yongchun Zhu and Yitai Qian
Energy & Environmental Science 2015 vol. 8(Issue 11) pp:3181-3186
Publication Date(Web):27 Jul 2015
DOI:10.1039/C5EE01470K
Polysulfide dissolution and the insulating nature of sulfur cause significant capacity fading and low efficiency in rechargeable lithium–sulfur batteries. Here, we show that these defects can be effectively diminished by immobilizing sulfur in porous carbon via the interaction of a small amount of selenium. Amorphous S-rich S1−xSex/C (x ≤ 0.1) composites have been prepared starting from Se and S powders at 260 °C. Raman spectra reveal the existence of S–Se bonds in S1−xSex/C composites. As cathodes for lithium–sulfur batteries, S1−xSex/C (x ≤ 0.1) composites exhibit high electrochemical performance in a carbonate-based electrolyte. S0.94Se0.06/C composites deliver the best performance with a capacity of 910 mA h g−1 at 1 A g−1 over 500 cycles, 1105 mA h g−1 at 0.2 A g−1 after 100 cycles and a good rate capability of 617 mA h g−1 at 20 A g−1.
Co-reporter:Xiaona Li;Jianwen Liang;Zhiguo Hou;Wanqun Zhang;Yan Wang;Yongchun Zhu
Advanced Functional Materials 2015 Volume 25( Issue 32) pp:5229-5238
Publication Date(Web):
DOI:10.1002/adfm.201501956
For lithium-selenium batteries, commercial applications are hindered by the inferior electrical conductivity of selenium and the low utilization ratio of the active selenium. Here, we report a new baked-in-salt approach to enable Se to better infiltrate into metal-complex-derived porous carbon (Se/MnMC-B). The approach uses the confined, narrow space that is sandwiched between two compact NaCl solid disks, thus avoiding the need for protection with argon or a vacuum environment during processing. The electrochemical properties for both lithium and sodium storage of our Se/MnMC-B cathode were found to be outstanding. For lithium storage, the Se/MnMC-B cathode (with 72% selenium loading) exhibited a capacity of 580 mA h g−1 after 1000 cycles at 1 C, and an excellent rate capability was achieved at 20 C and 510 mA h g−1. For sodium storage, a specific capacity of 535 mA h g−1 was achieved at 0.1 C after 150 cycles. These results demonstrate the potential of this approach as a new effective general synthesis method for confining other low melting point materials into a porous carbon matrix.
Co-reporter:Jianwen Liang, Xiaona Li, Zhiguo Hou, Tianwen Zhang, Yongchun Zhu, Xuedong Yan, and Yitai Qian
Chemistry of Materials 2015 Volume 27(Issue 11) pp:4156
Publication Date(Web):May 12, 2015
DOI:10.1021/acs.chemmater.5b01527
Macro-Ge powder has been synthesized with a novel hydrothermal reduction of commercial GeO2 at 200 °C in an autoclave. The obtained macro-Ge product demonstrates a honeycomb-like macroscopic network structure with a high tap density of 2.19 g cm–3. As for the anode material of lithium ion batteries, the macro-Ge electrode exhibits 1350 mAh g–1 at the current rate of 0.2 C and with 64% capacity retention over 3500 total cycles at 1 C. The macro-Ge contains a honeycomb porous structure, which allows for a high volumetric capacity (∼3000 mAh cm–3). Moreover, the symmetrical and asymmetric rate behaviors also provide its excellent electrochemical property. For example, the macro-Ge electrode can be rapidly charged to 1130 mAh g–1 in 3 min (20 C) and 890 mAh g–1 in 90 s (40 C) using the constant discharge mode of 1 C. Furthermore, the Ge electrode still maintains over 1020 mAh g–1 at 1 C for 300 cycles at the high temperature (55 °C) environment. When coupled with a commercial LiCoO2 cathode, a 3.5 V lithium-ion battery with capacity retention of 91% (∼364 Wh kg–1) over 100 cycles is achieved. These outstanding properties may be attributed to the honeycomb structure, for which the porous architectures supply the high efficient ionic transport and buffers the volume change during the lithiation/delithiation processes. Moreover, with bulk frameworks it ensures the high tap density and further improves the energy density. It is supported that the macro-Ge acts as attractive anode materials for further application in rechargeable lithium ion batteries.
Co-reporter:Ning Lin, Jie Zhou, Jianbin Zhou, Ying Han, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2015 vol. 3(Issue 34) pp:17544-17548
Publication Date(Web):29 Jul 2015
DOI:10.1039/C5TA04354A
Commercial micron-sized bulk Si is chemically converted into a nano-sized Si/Cu/C ternary composite. The Si particles, Cu crystals, and amorphous carbon are generated synchronously and mixed uniformly. As an anode, the Si/Cu/C exhibits a capacity of 1560 mA h g−1 after 80 cycles at 0.5 mA g−1, long-term cycling stability with a capacity of 757 mA h g−1 at 2 A g−1 after 600 cycles, and fine rate capability.
Co-reporter:Ning Lin, Liangbiao Wang, Jianbin Zhou, Jie Zhou, Ying Han, Yongchun Zhu, Yitai Qian and Changhe Cao
Journal of Materials Chemistry A 2015 vol. 3(Issue 21) pp:11199-11202
Publication Date(Web):17 Apr 2015
DOI:10.1039/C5TA02216A
A Si/Ge nanocomposite composed of interconnected Si and Ge nanoparticles is prepared through a one-step solid-state metathesis reaction between Mg2Si and GeO2 for the first time. As an anode, the Si/Ge electrode exhibits a reversible capacity of 2404.7 mA h g−1 at 0.5 A g−1 over 60 cycles and long-term cycling stability with a capacity of 1260 mA h g−1 over 500 cycles even at 5 A g−1.
Co-reporter:Jianbin Zhou, Ning Lin, Liangbiao Wang, Kailong Zhang, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2015 vol. 3(Issue 14) pp:7463-7468
Publication Date(Web):25 Feb 2015
DOI:10.1039/C5TA00516G
Hexagonal MoO3 nanorods with an average diameter of 40 nm have been synthesized in an immiscible mixture of water and methylbenzene. Both citric acid, which can chelate molybdic acid in water solution, and the interface reaction occurring between the two phases of the mixture are favorable for the formation of hexagonal MoO3 nanorods. As an anode material for lithium-ion batteries, hexagonal MoO3 nanorods exhibit a capacity of over 780 mA h g−1 after 150 cycles at 150 mA g−1, which is higher than that of hexagonal MoO3 microrods with diameters of 2–3 μm.
Co-reporter:Long Fan, Jingjing Zhang, Jianhua Cui, Yongchun Zhu, Jianwen Liang, Lili Wang and Yitai Qian
Journal of Materials Chemistry A 2015 vol. 3(Issue 7) pp:3276-3280
Publication Date(Web):14 Jan 2015
DOI:10.1039/C4TA06771A
Rod-like Sb–C composite has been synthesized by a synchronous reduction and carbon deposition process. The Sb–C composite anode exhibits a reversible capacity of 478.8 mA h g−1 at 100 mA g−1 after 100 cycles for Li-ion batteries and exhibits a reversible capacity of 430.9 mA h g−1 at 50 mA g−1 after 100 cycles for Na-ion batteries.
Co-reporter:Zhiguo Hou, Xiaona Li, Jianwen Liang, Youngchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2015 vol. 3(Issue 4) pp:1400-1404
Publication Date(Web):28 Nov 2014
DOI:10.1039/C4TA06018K
Due to the costly short-term transients, frequency regulation, and load balancing, the electrical power grid faces an urgent need for large-scale energy storage. The long durability, high power and energy density, and low cost needed for stationary energy storage posing constant challenges for conventional battery technology inspire people to explore new kinds of energy storage technologies. Here, we assembled an aqueous rechargeable sodium ion battery by using NaMnO2 as a cathode material and NaTi2(PO4)3/C composites as anode materials in 2 M CH3COONa aqueous electrolyte. This battery system could work in a wide voltage range from 0.5 V to 1.8 V, giving an energy density of 30 W h kg−1 (based on the total mass of active materials) and could retain 75% of the initial capacity after 500 cycles at the 5 C rate. What is more, the earth-abundant precursors, environmental friendliness and inherent safety made this battery system particularly attractive for stationary energy storage applications.
Co-reporter:Jianbin Zhou, Ning Lin, Ying Han, Jie Zhou, Yongchun Zhu, Jin Du and Yitai Qian
Nanoscale 2015 vol. 7(Issue 37) pp:15075-15079
Publication Date(Web):24 Aug 2015
DOI:10.1039/C5NR04456A
Cu3Si@Si core–shell nanoparticles with a Si shell coated over the Cu3Si core are synthesized by a solid-state reaction between CuCl and Si. The evaluation process of the core–shell structure shows a mechanism analogous to the Kirkendall effect. As anode materials for lithium ion batteries, Cu3Si@Si core–shell nanoparticles retained a capacity of 903.6 mA h g−1 at the current density of 2 A g−1 over 400 cycles.
Co-reporter:Cong Guo, Lili Wang, Yongchun Zhu, Danfeng Wang, Qianqian Yang and Yitai Qian
Nanoscale 2015 vol. 7(Issue 22) pp:10123-10129
Publication Date(Web):05 May 2015
DOI:10.1039/C5NR01953B
Fe3O4 nanoflakes in an N-doped carbon matrix (Fe3O4 NF@NC) were prepared by solvothermal synthesis of Fe3O4 nanoflakes and in situ polymerization of pyrrole on the surface of Fe3O4 followed by heat treatment. The Fe3O4 NF@NC is composed of Fe3O4 nanoflakes with a width of 50–60 nm and a thickness of 10 nm dispersed in the N-doped carbon matrix. The carbon content varies from 18% to 50% on controlling the amount of pyrrole added, therefore the Fe3O4 NF@NC with 44% carbon content performs the best. Due to the cooperation of the two-dimensional (2D) structure of Fe3O4 nanoflakes and the N-doped carbon matrix, the obtained Fe3O4 NF@NC (44% carbon content) exhibits electrochemical performance with a reversible capacity of 1046 mA h g−1 at 0.2 C (1 C = 924 mA g−1) over 200 cycles, 662 mA h g−1 at 1 C after 500 cycles and 600 mA h g−1 at 5 C over 200 cycles.
Co-reporter:Ning Lin, Jie Zhou, Ying Han, Kailong Zhang, Yongchun Zhu and Yitai Qian
Chemical Communications 2015 vol. 51(Issue 96) pp:17156-17159
Publication Date(Web):05 Oct 2015
DOI:10.1039/C5CC06178D
Direct metathesis reaction between Mg2Ge and SnCl4 is introduced to prepare porous hierarchical Ge–Sn binary composites, in which the Ge and Sn components are distributed uniformly, with a tap density of 2.3 g cm−3. As an anode for LIBs, the Ge–Sn composite displays a specific capacity of 980 mA h g−1 at 0.5 A g−1 after 250 cycles, and 890 mA h g−1 at 3 A g−1 over 1700 cycles. When paired with a commercial LiCoO2 cathode, a 3.6 V full battery with a capacity of 830 mA h g−1 is obtained.
Co-reporter:Jianwen Liang, Xiaona Li, Zhiguo Hou, Cong Guo, Yongchun Zhu and Yitai Qian
Chemical Communications 2015 vol. 51(Issue 33) pp:7230-7233
Publication Date(Web):19 Mar 2015
DOI:10.1039/C5CC01659B
Nanoporous silicon has been prepared through the air-oxidation demagnesiation of Mg2Si at 600 °C for 10 hours (Mg2Si + O2 → Si + MgO), followed by HCl washing. Mg2Si was prepared from 200 mesh commercial Si at 500 °C for 5 h in an autoclave. The as-prepared Si exhibits a reversible capacity of 1000 mA h g−1 at 36 A g−1 and ∼1200 mA h g−1 at 1.8 A g−1 over 400 cycles.
Co-reporter:Xiaona Li, Jianwen Liang, Zhiguo Hou, Yongchun Zhu, Yan Wang and Yitai Qian
Chemical Communications 2015 vol. 51(Issue 18) pp:3882-3885
Publication Date(Web):29 Jan 2015
DOI:10.1039/C5CC00080G
A novel approach via reduction and carbonization of germanium chelate synchronously to in situ formed uniform Ge–carbon hybrid nanoparticles has been developed. The Ge–carbon composites, derived from the homogenous dispersion of the elements within the chelate complex matrix at the molecular level, exhibit outstanding electrochemical lithium-storage performance with high capacity, excellent rate capability, and ultra long cycling life.
Co-reporter:Liangbiao Wang, Ning Lin, Jianbing Zhou, Yongchun Zhu and Yitai Qian
Chemical Communications 2015 vol. 51(Issue 12) pp:2345-2348
Publication Date(Web):22 Dec 2014
DOI:10.1039/C4CC09233C
Silicon (Si) nanoparticles have been prepared by a “metathesis” reaction of magnesium silicide (Mg2Si) and zinc chloride (ZnCl2) in an autoclave at 300 °C. The as-prepared Si nanoparticles exhibit a reversible capacity of 795 mA h g−1 at a current density of 3.6 A g−1 over 250 cycles.
Co-reporter:Ning Lin, Jianbin Zhou, Liangbiao Wang, Yongchun Zhu, and Yitai Qian
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 1) pp:409
Publication Date(Web):December 11, 2014
DOI:10.1021/am506404b
A novel approach to fabricate Si@carbon/reduced graphene oxides composite (Si@C/RGO) assisted by polyaniline (PANI) is developed. Here, PANI not only serves as “glue” to combine Si nanoparticles with graphene oxides through electrostatic attraction but also can be pyrolyzed as carbon layer coated on Si particles during subsequent annealing treatment. The assembled composite delivers high reversible capacity of 1121 mAh g–1 at a current density of 0.9 A g–1 over 230 cycles with improved initial Coulombic efficiency of 81.1%, while the bare Si and Si@carbon only retain specific capacity of 50 and 495 mAh g–1 at 0.3 A g–1 after 50 cycles, respectively. The enhanced electrochemical performance of Si@C/RGO can be attributed to the dual protection of carbon layer and graphene sheets, which are synergistically capable of overcoming the drawbacks of inner Si particles such as huge volume change and low conductivity and providing protective and conductive matrix to buffer the volume variation, prevent the Si particles from aggregating, enhance the conductivity, and stabilize the solid–electrolyte interface membrane during cycling. Importantly, this method opens a novel, universal graphene coating strategy, which can be extended to other fascinating anode and cathode materials.Keywords: dual protection; graphene; lithium-ion batteries; polyaniline assistance; Si particles
Co-reporter:Xiaona Li, Jianwen Liang, Zhiguo Hou, Wanqun Zhang, Yan Wang, Yongchun Zhu, Yitai Qian
Journal of Power Sources 2015 Volume 293() pp:868-875
Publication Date(Web):20 October 2015
DOI:10.1016/j.jpowsour.2015.06.031
•Galvanostatic cycling in half-cells was applied for prelithiating Ge/C electrodes.•Different pre-lithiated degrees influence the corresponding full cell performance.•After appropriate pre-lithiation, the Ge/LiCoO2 cell exhibits high energy density.High capacity electrodes based on Ge composite anode and commercial LiCoO2 cathode, are evaluated and combined to fabricate a high energy lithium ion battery. The Ge composite anode, Ge/CHNs (Ge/carbon hybrid nanoparticles), is prepared with a co-precipitation followed by pyrolysis process, delivering a capacity of >1000 mA h g−1 over 2000 cycles. While for full cell assembling, galvanostatic cycling in lithium half-cells has been applied for prelithiating Ge/CHNs anodes to eliminate the first cycle irreversible capacity loss. Such process is shown to enable capacity matching between Ge/CHNs anodes and LiCoO2 cathodes, further influence the working voltage and cycle stability of the full cells. Finally, the lithium ion battery system based on the prelithiated Ge/CHNs anode and LiCoO2 cathode demonstrates a high energy density of 370 Wh kg−1 after 300 cycles between 2.7 and 4.4 V at 1C (the energy density here is based on the total weight of Ge/CHNs and LiCoO2), with average capacity fading about 0.018% per cycle. Thus, the designed battery system is promising candidate for energy storage applications with demand of high energy density and long cycle life.
Co-reporter:Kailong Zhang, Xiaona Li, Jianwen Liang, Yongchun Zhu, Lei Hu, Qiushi Cheng, Cong Guo, Ning Lin, Yitai Qian
Electrochimica Acta 2015 Volume 155() pp:174-182
Publication Date(Web):10 February 2015
DOI:10.1016/j.electacta.2014.12.108
Nitrogen-doped porous interconnected double-shelled hollow carbon spheres (N-DHCSs) have been synthesized by chemical treatment of Fe3O4@C precursors using HNO3 at low temperature. When the precursors are disposed with HCl or H2SO4, uniform porous interconnected double-shelled hollow carbon spheres (DHCSs) are prepared. Comparing with DHCSs, the as-prepared N-DHCSs show higher Li-storage capacity and both show good cycling stability as anode materials in lithium ion batteries. The N-DHCSs offer a capacity of 512 mA h g−1 at 1.5 C after 500 cycles and their porous interconnected double-shelled hollow structure could be well kept. The N-DHCSs also show high reversible capacity of 598 mA h g−1 at 1 C after cycled at different current densities. In addition, the N-DHCSs as anode materials in sodium half-cell exhibit high reversible capacity of 120 mA h g−1 at a current rate of 0.2 A g−1 after 100 cycles.
Co-reporter:Zhiguo Hou, Xueqian Zhang, Jianwen Liang, Xiaona Lia, Xuedong Yan, Yongchun Zhu and Yitai Qian
RSC Advances 2015 vol. 5(Issue 87) pp:71355-71359
Publication Date(Web):17 Aug 2015
DOI:10.1039/C5RA13155C
Si@C composites have been solvothermally synthesized by the reaction of ethanol or acetone with Mg2Si at 650 °C, followed by HCl washing. Ethanol or acetone can oxidise Mg2Si to form Si, and at the same time, they are reduced to synchronously form carbon coated on the surface of the generated Si nanoparticles. As lithium ion battery anode, the as-synthesized Si@C composites obtained from the reaction of acetone with Mg2Si deliver a reversible capacity of 3277 mA h g−1 at 0.36 A g−1 and remain 892 mA h g−1 at 3.6 A g−1 after 350 cycles.
Co-reporter:Kailong Zhang, Tingwei Zhang, Jianwen Liang, Yongchun Zhu, Ning Lin and Yitai Qian
RSC Advances 2015 vol. 5(Issue 19) pp:14828-14831
Publication Date(Web):20 Jan 2015
DOI:10.1039/C4RA14819C
Fe7S8@C nanospheres were prepared by a simple solid–solid reaction and showed a high specific capacity and an excellent high rate performance as the anode material in lithium ion batteries. The core–shell Fe7S8@C composites delivered a very high reversible capacity of 695 mA h g−1 at 0.1 A g−1 after 50 cycles between 0.01 and 3.00 V. The Fe7S8@C composites also showed a discharge plateau at 1.5 V, cycling between 1.20 and 2.50 V, and exhibited a specific capacity of 397 mA h g−1 at 0.1 A g−1 over 200 cycles, which is higher than the theoretical capacity of Li4Ti5O12 (about 175 mA h g−1).
Co-reporter:Jingjing Zhang, Yanhua Xu, Long Fan, Yongchun Zhu, Jianwen Liang, Yitai Qian
Nano Energy 2015 Volume 13() pp:592-600
Publication Date(Web):April 2015
DOI:10.1016/j.nanoen.2015.03.028
•A novel nanocomposite of graphene–encapsulated selenium/polyaniline core–shell nanowires has been fabricated.•The G@Se/PANI was synthesized under the condition of low temperature without heating.•The G@Se/PANI nanocomposite exhibits enhanced cycling performance and high-rate capability.A novel nanocomposite of graphene–encapsulated selenium/polyaniline core–shell nanowires (G@Se/PANI) has been designed and synthesized under the condition of low temperature without heating and investigated as a cathode material for Li-ion batteries. In this nanocomposite, selenium nanowires are well-sealed in the PANI layer with a thickness of ≈25 nm forming a core/shell structure and then the Se/PANI core–shell nanowires are uniformly encapsulated in the graphene nanosheets. As expected, the G@Se/PANI nanocomposite exhibits enhanced cycling performance and high-rate capability. The G@Se/PANI nanocomposite displays a reversible discharge capacity of 567.1 mA h/g at 0.2 C after 200th cycle and 510.9 mA h/g at 2 C, which could be associated with the highly electrical conductivity of graphene sheets and the unique PANI shell, together with the one-dimensional structure of selenium in the G@Se/PANI nanocomposite.The novel nanocomposite of graphene–encapsulated selenium/polyaniline core–shell Nanowires (G@Se/PANI) displays excellent electrochemical performance for Li–Se batteries.
Co-reporter:Jianwen Liang;Xiaona Li;Yongchun Zhu;Cong Guo
Nano Research 2015 Volume 8( Issue 5) pp:1497-1504
Publication Date(Web):2015 May
DOI:10.1007/s12274-014-0633-6
There have been few reports concerning the hydrothermal synthesis of silicon anode materials. In this manuscript, starting from the very cheap silica sol, we hydrothermally prepared porous silicon nanospheres in an autoclave at 180 °C. As anode materials for lithium-ion batteries (LIBs), the as-prepared nano-silicon anode without any carbon coating delivers a high reversible specific capacity of 2,650 mAh·g−1 at 0.36 A·g−1 and a significant cycling stability of about 950 mAh·g−1 at 3.6 A·g−1 during 500 cycles.
Co-reporter:Denghu Wei, Xiaona Li, Yongchun Zhu, Jianwen Liang, Kailong Zhang and Yitai Qian
Nanoscale 2014 vol. 6(Issue 10) pp:5239-5244
Publication Date(Web):11 Mar 2014
DOI:10.1039/C4NR00250D
A peony-like Ag/Ag0.68V2O5 hybrid assembled from nanosheets with the thickness of 40 nm was synthesized through a one-pot hydrothermal approach from vanadium pentoxide (V2O5), oxalic acid (H2C2O4), and silver nitrate (AgNO3) at 180 °C for 24 h. The hybrid exhibits high performance as both anode and cathode materials for rechargeable lithium batteries. Electrochemical measurements revealed that the as-prepared Ag/Ag0.68V2O5 hybrid displayed excellent cycling stability, especially as an anode material. The resulting anode retains 100% of the initial capacity after 1000 cycles under a current density of 400 mA g−1. This phenomenon may be attributed to electron conductivity improvement by the existence of metallic silver in the hybrid in addition to the convenient access to lithium ion ingress/egress because of its unique structure.
Co-reporter:Lili Wang, Cong Guo, Yongchun Zhu, Jianbin Zhou, Long Fan and Yitai Qian
Nanoscale 2014 vol. 6(Issue 23) pp:14174-14179
Publication Date(Web):10 Oct 2014
DOI:10.1039/C4NR05070C
A composite with FeCl2 nanocrystals sandwiched between Cl-doped graphite layers has been created via a space-confined nanoreactor strategy. This composite can be used as a new type of anode material for Li-ion batteries, which exhibit high reversible capacity and superior rate capability with excellent cycle life.
Co-reporter:Jingjing Zhang, Long Fan, Yongchun Zhu, Yanhua Xu, Jianwen Liang, Denghu Wei and Yitai Qian
Nanoscale 2014 vol. 6(Issue 21) pp:12952-12957
Publication Date(Web):02 Sep 2014
DOI:10.1039/C4NR03705G
A kind of Se/C nanocomposite is fabricated by dispersing selenium in interconnected porous hollow carbon bubbles (PHCBs) via a melt-diffusion method. Such PHCBs are composed of porous hollow carbon spheres with a size of ∼70 nm and shells of ∼12 nm thickness interconnected to each other. Instrumental analysis shows that the porous shell of the PHCBs could effectively disperse and sequester most of the selenium, while the inner cavity remains hollow. When evaluated as cathode materials in a carbonate-based electrolyte for Li–Se batteries, the Se/PHCBs composites exhibit significantly excellent cycling performance and a high rate capability. Especially, the Se/PHCBs composite with an optimal content of ∼50 wt% selenium (Se50/PHCBs) displays a reversible discharge capacity of 606.3 mA h g−1 after 120 cycles at 0.1 C charge–discharge rate. As the current density increased from 0.1 to 1 C (678 mA g−1), the reversible capacity of the Se50/PHCBs composite can still reach 64% of the theoretical capacity (431.9 mA h g−1). These outstanding electrochemical features should be attributed to effective sequestration of Se in the PHCBs, as well as to the ability to accommodate volume variation and enhance the electronic transport by making Se have close contact with the carbon framework.
Co-reporter:Xing Zhang, Yitai Qian, Yongchun Zhu and Kaibin Tang
Nanoscale 2014 vol. 6(Issue 3) pp:1725-1731
Publication Date(Web):04 Nov 2013
DOI:10.1039/C3NR05551E
Mn2O3 has been demonstrated to be a promising electrode material for lithium-ion batteries. Thus, the fabrication of Mn2O3 nanomaterials with high specific capacity and cycling stability is greatly desired. Here we report a simple but effective method to synthesis Mn2O3 nanomaterials from a Mn(OH)2 precursor, which was prepared from manganese acetate in ethylene glycol and water at 180 °C for 12 h. The morphology and sheet thickness of Mn(OH)2 precursor could be tuned by controlling the ethylene glycol/H2O volume ratio, resulting in a further tunable morphology and sheet thickness of the porous Mn2O3 nanomaterials. In the electrochemical tests the prepared Mn2O3 nanomaterials, with the porous architecture and thin thickness exhibited a high and stable reversible capacity, indicating that both small thickness and porous sheets structure are crucial for improving the electrochemical performance of Mn2O3 in terms of specific capacity and stability.
Co-reporter:Ning Lin, Jianbin Zhou, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2014 vol. 2(Issue 46) pp:19604-19608
Publication Date(Web):08 Oct 2014
DOI:10.1039/C4TA05089D
A Si/reduced graphene oxide composite with 3D framework is constructed by a typical cross-linking reaction between polyacrylamide and graphene oxides, which delivers a high reversible capacity of 1610 mA h g−1 at 1.2 A g−1 after 200 cycles, good rate capability, and cycling stability with negligible capacity degradation over 200 cycles.
Co-reporter:Jie Yue, Xin Gu, Liang Chen, Nana Wang, Xiaolei Jiang, Huayun Xu, Jian Yang and Yitai Qian
Journal of Materials Chemistry A 2014 vol. 2(Issue 41) pp:17421-17426
Publication Date(Web):27 Aug 2014
DOI:10.1039/C4TA03924F
The use of manganese oxides as promising candidates for anode materials in lithium ion batteries has attracted a significant amount of attention recently. Here, we develop a general approach to synthesize hollow nanospheres of MnO2, Mn3O4 and MnO, using carbon nanospheres as a template and a reagent. Depending on the calcination temperature, time and atmosphere, hollow nanospheres of MnO2 assembled by randomly dispersed nanosheets, or hollow nanospheres of Mn3O4 and MnO composed of aggregated nanoparticles, are produced. The electrochemical properties of the three hollow nanoparticles are investigated in terms of cycling stability and rate capability. They deliver the specific capacities of 840, 1165 or 1515 mA h g−1 after 60 cycles at 100 mA g−1 for MnO2, Mn3O4 and MnO. Even at 500 mA g−1, the reversible capacities could be still kept at 637, 820, and 1050 mA h g−1 after 150 cycles. The outstanding performances might be related with their hollow structure, porous surface and nanoscale size.
Co-reporter:Qiushi Cheng, Jianwen Liang, Yongchun Zhu, Lulu Si, Cong Guo and Yitai Qian
Journal of Materials Chemistry A 2014 vol. 2(Issue 41) pp:17258-17262
Publication Date(Web):03 Sep 2014
DOI:10.1039/C4TA04184D
Ti2Nb10O29 is fabricated directly by solid-state reaction from commercial TiO2 and Nb2O5. Without further modification, the bulk Ti2Nb10O29 anode exhibits a reversible capacity of 144 mA h g−1 at 10 C after 800 cycles. More impressively, the capacity of the Ti2Nb10O29/LiFePO4 full-cell at 1 C stabilizes at 100 mA h g−1 after 1000 cycles.
Co-reporter:Lulu Si, Zhengqiu Yuan, Jianwen Liang, Lei Hu, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2014 vol. 2(Issue 25) pp:9784-9791
Publication Date(Web):30 Apr 2014
DOI:10.1039/C4TA01234H
Carbon-coated one-dimensional (1-D) SnO2/MoO3 nanostructure (SnO2/MoO3/C) composed of densely stacked SnO2 nanosheets, uniformly distributing in amorphous MoO3 matrix, is obtained from the 1-D SnO2/MoO3 heterostructure, which is prepared for the first time by a facile, one-pot hydrothermal method. The precursor 1-D SnO2/MoO3 heterostructure is composed of SnO2 nanosheets, adhering to the two edges of 1-D MoO3 nanobelt by lattice matching between the (140) plane of orthorhombic MoO3 and (110) plane of rutile SnO2. By prolonging the hydrothermal reaction time, the as-obtained 1-D SnO2/MoO3 heterostructure is converted to a novel 1-D nanostructure, amorphous MoO3 that deposits uniformly on the surface of the SnO2 nanosheets with the preservation of the front SnO2 1-D architecture. For optimizing performance, 1-D SnO2/MoO3/C nanostructure is obtained by carbon coating on the surface of the novel 1-D nanostructure MoO3/SnO2via the pyrolysis of acetylene. Because of the 1-D nanostructure composed of nanosheets and the carbon matrix, the SnO2/MoO3/C nanocomposites exhibit an outstanding high-rate cycling performance, delivering a reversible discharge capacity of more than 560 mA h g−1 after 120 cycles at a high current density of 200 mA g−1.
Co-reporter:Linlin Wang, Wanqun Zhang, Caihua Wang, Dake Wang, Zhongping Liu, Qiaoyan Hao, Yan Wang, Kaibin Tang and Yitai Qian
Journal of Materials Chemistry A 2014 vol. 2(Issue 14) pp:4970-4974
Publication Date(Web):17 Jan 2014
DOI:10.1039/C3TA14563H
CdSnO3 materials have been extensively studied as gas-sensing materials. However, there are few reports on the synthesis and use of porous CdSnO3 nanostructures for energy storage. Herein, we report highly porous CdSnO3 nanoparticles prepared using citric acid with sizes in the range of ∼7.8 nm to 28.7 nm and the application of these nanoparticles as an anode material for rechargeable Li-ion batteries (LIBs). Electrochemical measurements showed that the highly porous CdSnO3 nanoparticles delivered a high reversible capacity of ∼515 mA h g−1 for up to 40 cycles at a current rate of 70 mA g−1. Even at a high rate of 150 mA g−1, the porous CdSnO3 could still deliver a capacity of 506 mA h g−1. It is observed that the electrochemical performance of the highly porous CdSnO3 nanoparticles is much better than that (∼370 mA h g−1 for up to 40 cycles) of a counterpart obtained without citric acid, which also demonstrates the capacity enhancement and high rate capacity.
Co-reporter:Jingjing Zhang, Jianwen Liang, Yongchun Zhu, Denghu Wei, Long Fan and Yitai Qian
Journal of Materials Chemistry A 2014 vol. 2(Issue 8) pp:2728-2734
Publication Date(Web):10 Dec 2013
DOI:10.1039/C3TA13228E
A Co2SnO4 hollow cube/graphene composite (Co2SnO4 HC@rGO) was synthesized by pyrolysis-induced transformation from the hydrothermally synthesized hollow cubic precursor and subsequent combination with graphene sheets via the analogous mechanism of electrostatic interactions. The Co2SnO4 HCs with a size of 240 nm and the shell of 50–70 nm thickness were uniformly encapsulated in the graphene sheets. As an anode material for lithium-ion batteries, the Co2SnO4 HC@rGO exhibited significantly enhanced cyclability and superior rate capability compared to the pure Co2SnO4 counterpart. Even after 100 cycles, it still delivered a capacity over 1000 mA h g−1 at 100 mA g−1.
Co-reporter:Xiaona Li, Jianwen Liang, Zhiguo Hou, Yongchun Zhu, Yan Wang and Yitai Qian
Chemical Communications 2014 vol. 50(Issue 90) pp:13956-13959
Publication Date(Web):12 Sep 2014
DOI:10.1039/C4CC06658H
A new (NH4)3H(Ge7O16)(H2O)2.72 precursor-pyrolyzation approach was designed and developed for the facile synthesis of nanostructured GeO2, avoiding the use of any hazardous or expensive germanium compounds. The products show promising anode application in lithium ion batteries with high capacity and excellent cycling stability.
Co-reporter:Jianwen Liang, Denghu Wei, Ning Lin, Youngchun Zhu, Xiaona Li, Jingjing Zhang, Long Fan and Yitai Qian
Chemical Communications 2014 vol. 50(Issue 52) pp:6856-6859
Publication Date(Web):18 Mar 2014
DOI:10.1039/C4CC00888J
Honeycomb porous silicon (hp-Si) has been synthesized by a low temperature (200 °C) magnesiothermic reduction of Na2SiO3·9H2O. This process can be regarded as a general synthesis method for other silicide materials. Significantly, hp-Si features excellent electrochemical properties after graphene coating.
Co-reporter:Xiaona Li, XiaoBo Zhu, Yongchun Zhu, Zhengqiu Yuan, LuLu Si, Yitai Qian
Carbon 2014 Volume 69() pp:515-524
Publication Date(Web):April 2014
DOI:10.1016/j.carbon.2013.12.059
Porous nitrogen-doped carbon vegetable-sponges (N-DCSs) have been fabricated by chemical treatment of the Cu@C precursors using HNO3 for the first time. The obtained N-DCSs are porous three-dimensional (3D)-structure and similar to numerous agglomerated fluffy micro-vegetable-sponges. When the precursors are treated by H2SO4, carbon vegetable-sponges (CSs) without nitrogen doping are prepared. As anode materials in lithium ion batteries, the as-prepared N-DCSs show improved Li-storage capacity and cycling stability as compared with the pure CSs. They offer 870 mA h g−1 at 0.5 A g−1 after 300 cycles and high reversible capacity with 910 mA h g−1 at 0.2 A g−1 after cycled at different current densities, which are much higher than those of CSs. It is envisaged that the large surface area, unique 3D porous nanostructure and appropriate nitrogen doping are favorable for the superior electrochemical properties of N-DCSs.
Co-reporter:Xiaobo Zhu, Xiaona Li, Youngchun Zhu, Shasha Jin, Yan Wang, Yitai Qian
Journal of Power Sources 2014 Volume 261() pp:93-100
Publication Date(Web):1 September 2014
DOI:10.1016/j.jpowsour.2014.03.047
•Porous LiNi0.5Mn1.5O4 microspheres are produced through a simple two-step method.•The pore condition is able to be altered by changing the lithium sources.•Microspheres with larger pores exhibit excellent rate and cycle performance.•Tinier pores coupled with larger surface area show distinct disadvantages.Here two types of LiNi0.5Mn1.5O4 (LNMO) microspheres with different pore conditions are prepared through a facile two-step method. Initially, nickel manganese carbonate microspheres are obtained through a solvothermal reaction, and then they are heated with different lithium sources to obtain the two products. Scanning electron microscopy images clearly disclose that the two types of microspheres are respectively covered with dense tinier pores and sparse larger pores while both of their interiors are constituted by nanoparticles in similar size. Nitrogen adsorption/desorption analyses indicate that their maximum pore diameters are 2.2 nm and 3.5 nm. As cathodes of lithium ion batteries, the LNMO microspheres equipped with larger pores exhibit much more excellent electrochemical performance especially in terms of rate performance, achieving a discharge capacity of 101.7 mAh g−1 even at 50C, while their counterparts only receive 14.3 mAh g−1 coupled with severe polarization. And the capacities of them respectively maintain at 102.9 and 67 mAh g−1 after 100 cycles at 20C. Their distinct performance is suggested due to both the pore parameter and its related surface area.Two types of LNMO microspheres with different pore conditions are produced for lithium battery cathodes, resulting in distinct electrochemical performance.
Co-reporter:Xiaobo Zhu, Xiaona Li, Yongchun Zhu, Shasha Jin, Yan Wang, Yitai Qian
Electrochimica Acta 2014 Volume 121() pp:253-257
Publication Date(Web):1 March 2014
DOI:10.1016/j.electacta.2013.12.176
•LiNi0.5Mn1.5O4 nanostructures are prepared from urchin-like γ-MnO2.•Subsequent annealing brings about different phase and cationic composition.•Two-phase intergrowth is observed in the sample without annealing treatment.•The special structural characteristics endow the sample enhanced performance.LiNi0.5Mn1.5O4 (LNMO) nanostructures (microspheres composed of nanoparticles) are prepared from urchin-like γ-MnO2 by calcinating under 800 °C, the product shows Fd3m-based phase involving minor rock salt phase and Mn3+ ions confirmed by its Raman spectra, X-ray diffraction pattern and electrochemical activities. Furthermore, HRTEM images and EDS line-scanning spectroscopy patterns focusing on a single nanoparticle provide direct observation of intergrowth of two phases that minor P4332 phase is found on the edge of Fd3 m body coupled with the varying Mn/Ni ratio. In comparison, the other sample is obtained by adding an annealing treatment at 700 °C after calcinating at 800 °C, which preserves the nanostructured architecture of C800 and displays all the structural characteristics of pure P4332 phase. As cathode materials for lithium-ion batteries, merely calcined sample receives discharge capacities of 91 mAh•g−1 even at 50 C, and 100.5 mAh•g−1 after 300 cycles at 5 C, which shows better combination of rate and cycling performances than its counterpart with pure P4332 phase.
Co-reporter:Denghu Wei, Jianwen Liang, Yongchun Zhu, Lei Hu, Kailong Zhang, Jingjing Zhang, Zhengqiu Yuan, Yitai Qian
Electrochemistry Communications 2014 Volume 38() pp:124-127
Publication Date(Web):January 2014
DOI:10.1016/j.elecom.2013.11.021
•α-FeSe/C composites are prepared by a one-pot reaction.•They deliver a reversible capacity of 350 mAh g-1 located at 1.5 V.•The electrochemical reaction mechanism is investigated by ex situ XRD.Carbon-coated α-FeSe nanoparticles in an average size of 200 nm have been prepared by a facile one-pot reaction. As an anode material for lithium batteries, the core-shell α-FeSe@C composites showed a discharge plateau at 1.5 V, which could effectively avoid the formation of the lithium dendrites and the solid-electrolyte interface layer. They delivered a sustainable reversible capacity of 340 mAh g− 1 after 40 cycles, which is about twice as much as that of the Li4Ti5O12 (175 mAh g− 1), thereby indicating its promising applications for lithium storage.
Co-reporter:Long Fan, Yongchun Zhu, Jingjing Zhang, Jianwen Liang, Lili Wang, Denghu Wei, Xiaona Li, Yitai Qian
Electrochimica Acta 2014 Volume 121() pp:21-26
Publication Date(Web):1 March 2014
DOI:10.1016/j.electacta.2013.12.117
•An acetylene reduction route is designed to synthesis uniformly dispersed Sn-MnO@C nanocomposite.•Synchronously formed Sn and MnO nanocrystalline are uniformly dispersed in the amorphous carbon matrix.•The composite shows a reversible capacity of 684 mA h g−1 after 280 cycles.•Fine electrochemical performance attributes to uniformly dispersed nanoparticles, porous structure and carbon matrix coating.Uniformly dispersed carbon coated Sn-MnO nanocomposite (Sn-MnO@C) has been fabricated by thermal annealing of MnSn(OH)6 nanoparticles precursor in acetylene/argon gas (1/9; v/v). Benefiting from this unique method, the synchronously formed Sn and MnO nanocrystals both with size about 12 nm were uniformly dispersed in the amorphous carbon matrix. Meanwhile, a porous structure appeared which could be attributed to the dehydration of MnSn(OH)6 in the calcination process. As the anode for lithium-ion batteries, the Sn-MnO@C nanocomposite demonstrates a reversible capacity of 684 mA h g−1 after 280 cycles at a current of 100 mA g−1. The fine electrochemical performance mainly attributes to uniformly dispersed nanoparticles, porous structure as well as amorphous carbon matrix coating.
Co-reporter:Xiaolei Jiang, Huayun Xu, Jian Yang, Jing Liu, Hongzhi Mao and Yitai Qian
RSC Advances 2014 vol. 4(Issue 75) pp:39889-39893
Publication Date(Web):11 Aug 2014
DOI:10.1039/C4RA06392A
Carambola and jujube-seed-shaped Li2FeSiO4 assembled by nanoplates have been successfully synthesized by a simple hydrothermal method. The different morphologies are induced by two different iron precursors, which affect the self-organization behaviour of primary particles of Li2FeSiO4. The electrochemical performances of the two Li2FeSiO4/C composites are also influenced by the different morphology.
Co-reporter:Dr. Jianwen Liang;Dr. Denghu Wei;Dr. Qiushi Cheng;Dr. Yongchun Zhu;Dr. Xiaona Li;Dr. Long Fan;Dr. Jingjing Zhang ; Yitai Qian
ChemPlusChem 2014 Volume 79( Issue 1) pp:143-150
Publication Date(Web):
DOI:10.1002/cplu.201300324
Abstract
A new thread for improving the cycling stability of Fe2O3 nanorice is proposed through combining the electrochemical porousness (EP) effect and solid–electrolyte interphase (SEI) thermolysis approach. Starting from solid Fe2O3 nanorice, this process could be applied to prepare porous Fe2O3 nanorice with a good coating of a porous SEI thermolysis layer composed of carbon and Li2O. The interconnecting pores and full coating of the SEI thermolysis layer provides not only mechanical resistance of the Fe2O3 nanorice against pulverization, but also high electrical and ionic conductivity over the electrode throughout long cell cycles. This method results in the enhancement of cycling ability and capacity, which is demonstrated by comparison with the starting Fe2O3 nanorice. After the EP and SEI thermolysis approach, the Fe2O3 nanorice exhibits an energy capacity retention about of 680 mAh g−1 at a current density of 1000 mA g−1 over 250 cycles, which is more than 82 % of the initial reversible capacity. Moreover, it also has an excellent rate capability and high coulombic efficiency. This strategy provides a simple and convenient route toward stable charge/discharge cycling for not only Fe2O3, but also for other electrode materials that are subject to large volume changes and low charge voltages. At the same time, it also contributes to a fundamental understanding of improved cycling stability and reversible capacity for electrode materials.
Co-reporter:Dr. Lili Wang;Dr. Yongchun Zhu;Cong Guo;Xiaobo Zhu;Jianwen Liang; Yitai Qian
ChemSusChem 2014 Volume 7( Issue 1) pp:87-91
Publication Date(Web):
DOI:10.1002/cssc.201300874
Abstract
Ferric chloride-graphite intercalation compounds (FeCl3–GICs) with stage 1 and stage 2 structures were synthesized by reacting FeCl3 and expanded graphite (EG) in air in a stainless-steel autoclave. As rechargeable Li-ion batteries, these FeCl3–GICs exhibit high capacity, excellent cycling stability, and superior rate capability, which could be attributed to their unique intercalation features. This work may enable new possibilities for the fabrication of Li-ion batteries.
Co-reporter:Zhengqiu Yuan ; Lulu Si ; Denghu Wei ; Lei Hu ; Yongchun Zhu ; Xiaona Li
The Journal of Physical Chemistry C 2014 Volume 118(Issue 10) pp:5091-5101
Publication Date(Web):February 7, 2014
DOI:10.1021/jp410550v
The growth of mesoporous bundles composed of orthorhombic MoO3 nanowires with diameters ranging from 10 to 30 nm and lengths of up to 2 μm by topotactic chemical transformation from triclinic α-MoO3·H2O nanorods under vacuum condition at 260 °C is achieved. During the process of vacuum topotactic transformation, the nanorod frameworks of the precursor α-MoO3·H2O can be preserved. The crystal structures, molecular structures, morphologies, and growth behavior of the precursory, intermediate and final products are characterized using powder X-ray diffraction (PXRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected-area electron diffraction (SAED). Detailed studies of the mechanism of the mesoporous MoO3 nanowire bundles formation indicate topotactic nucleation and oriented growth of the well-organized orthorhombic MoO3 nanowires inside the nanorod frameworks. MoO3 nanocrystals prefer [001] epitaxial growth direction of triclinic α-MoO3·H2O nanorods due to the structural matching of [001] α-MoO3·H2O//[100] MoO3. The electrochemical measurement of the mesoporous MoO3 nanowire bundles indicates that their galvanostatic Li storage performance can be significantly improved. The high reversible capacities of 954.8 mA h g–1 can be retained over 150 cycles. The topotactic growth under vacuum based on the crystal structural relationship of hydrated metal oxide and related metal oxide will provide an effective and all-purpose route to controlled preparation of novel micro/nanostructured oxides (such as V2O5 and WO3 nanowires, etc.) with enhanced properties (energy storage/conversion, organic electronics, catalysis, gas-sensor, and so on).
Co-reporter:Nana Wang, Xiaojian Ma, Huayun Xu, Liang Chen, Jie Yue, Feier Niu, Jian Yang, Yitai Qian
Nano Energy 2014 Volume 6() pp:193-199
Publication Date(Web):May 2014
DOI:10.1016/j.nanoen.2014.04.001
•Porous ZnMn2O4 microspheres composed of interconnected nanoparticles have been prepared by a two-step process.•ZnMn2O4 microspheres exhibit a reversible capacity of 800 mAh g−1 at 500 mA g−1 over 300 cycles.•Even at 2 A g−1, ZnMn2O4 microspheres deliver a capacity of 395 mAh g−1, higher than the theoretical capacity of graphite.•The superior electrochemical performances can be associated with the porous structure and nanoscale building blocks.High-quality porous ZnMn2O4 microspheres composed of interconnected nanoparticles have been achieved by calcination of metal carbonates synthesized by a solvothermal reaction. The porous microspheres are characterized by XRD patterns, SEM, TEM, and HRTEM images to reveal the crystal phase and particle morphology. The porous structure and nanoscale building blocks of ZnMn2O4 microspheres make them a promising anode material for lithium ion batteries. After 300 cycles at a current density of 500 mA g−1, they still preserve a reversible capacity of 800 mAh g−1. Even at 2 A g−1, the reversible capacity could be 395 mAh g−1, higher than the theoretical capacity of graphite. The superior electrochemical performances can be associated with the porous structure and nanoscale building blocks, which promote the contacting between electrolyte and electrode, accommodate volume change during discharge/charge processes, and provide a large number of active surface sites for lithium storage.
Co-reporter:Lili Wang;Qiushi Chen;Yongchun Zhu
Science Bulletin 2014 Volume 59( Issue 32) pp:4271-4273
Publication Date(Web):2014 November
DOI:10.1007/s11434-014-0556-3
Graphene-wrapped Fe2O3 nanorings (RGO/Fe2O3) were synthesized by a facile approach, which assembled with graphene and the Fe2O3 nanorings precursor through the colloidal coagulation effect at room temperature. The uniform Fe2O3 nanorings prepared by hydrothermal routes were homogeneously distributed and well wrapped by graphene. When tested as anode for lithium ion batteries, RGO/Fe2O3 exhibits a high capacity and good cycling stability. This could be attributed to the interaction of ring-shaped structure and graphene sheets, which inherit the good kinetic property of Fe2O3 nanorings and enhance the structural integrity with graphene sheets’ support.
Co-reporter:Long Fan;Jingjing Zhang;Yongchun Zhu
Science Bulletin 2014 Volume 59( Issue 17) pp:2006-2011
Publication Date(Web):2014 June
DOI:10.1007/s11434-014-0278-6
Urchin-like Sn–ZnO–C composite have been successfully prepared by thermal annealing of ZnSn(OH)6 precursor in acetylene/argon gas (1/9; v/v). The phase of the urchin-like Sn–ZnO–C has been characterized by X-ray diffraction (XRD) and Raman spectrum. The images of scanning electron microscopy (SEM) and transmission electron microscope (TEM) demonstrate that the Sn–ZnO–C composite with an average of 3 μm in diameter is composed of many core–shell nanowires and carbon nanotubes emanated from the center. The thermal annealing temperature and time have crucial effects on the formation of urchin-like structure and carbon content of the Sn–ZnO–C composites. As an anode for lithium-ion batteries, the urchin-like Sn–ZnO–C composite delivers a discharge capacity of 1,034.5 mAh/g in initial cycle and 571.9 mAh/g reversible discharge capacity after 25 cycles at a current density of 50 mA/g. The superior energy storage properties highlight the urchin-like Sn–ZnO–C composite as a potential alternative anode material in lithium-ion batteries.
Co-reporter:Lili Wang, Jianwen Liang, Yongchun Zhu, Tao Mei, Xing Zhang, Qing Yang and Yitai Qian
Nanoscale 2013 vol. 5(Issue 9) pp:3627-3631
Publication Date(Web):06 Mar 2013
DOI:10.1039/C3NR00353A
Fe3O4@C core–shell nanorings (R-Fe3O4@C) were fabricated by a synchronous reduction and carbon deposition process. As the anodes for lithium-ion batteries, these R-Fe3O4@C exhibit a high capacity, excellent cycling stability and good rate performance. This ring-shaped core–shell nanostructure design may pave the way to enhance electrochemical performances of electrode materials.
Co-reporter:Xiaona Li, Yongchun Zhu, Xing Zhang, Jianwen Liang and Yitai Qian
RSC Advances 2013 vol. 3(Issue 25) pp:10001-10006
Publication Date(Web):23 Apr 2013
DOI:10.1039/C3RA41132J
MnO@1-D carbon composites were synthesized simultaneously through a single heating procedure using C4H4MnO6 as the precursor for both the MnO and 1-D carbon. MnO nanoparticles are uniformly dispersed inside or adhered to the surface of the 1-D carbon nanotubes, and these carbon nanotubes overlap each other to form carbon scaffolds. As an anode for lithium-ion batteries, the MnO@1-D carbon composites deliver a reversible capacity of 1482 mA h g−1 at a current density of 200 mA g−1. When the current density rises to 1460 mA g−1, the capacity remains at 810 mA h g−1 even after 1000 cycles. Such a unique carbon structure can act as a scaffold for MnO, which not only improves the electronic conductivity, but also provides a support for loading MnO nanoparticles. This synchronous process may pave a way to obtain such uniform and stable electrode materials with enhanced performance, which may find use in other applications such as catalysis, water treatment and supercapacitors.
Co-reporter:Linlin Wang, Wei Cheng, Huaxu Gong, Caihua Wang, Dake Wang, Kaibin Tang and Yitai Qian
Journal of Materials Chemistry A 2012 vol. 22(Issue 22) pp:11297-11302
Publication Date(Web):30 Mar 2012
DOI:10.1039/C2JM31023F
In this work, nanocrystalline-assembled bundle-like CuO structures were successfully synthesized in large-quantity by a friendly, facile two-step process. The bundle-like CuO particles are produced by thermolysis of bundle-like Cu(OH)2 precursors, which exhibit excellent high specific capacity, high stability, and especially high rate performance for anode materials in lithium-ion batteries, superior to that of most reported CuO-based anodes. The assembled structure of CuO endows it with high rate capacities of 666 mAh g−1, 609 mAh g−1, and 499 mAh g−1 at a current rate of 0.3 C, 1 C and 2 C after 50 cycles, respectively. Even at a high rate of 6 C, the bundle-like CuO can still deliver a capacity of 361 mAh g−1. It is observed that the electrochemical performance of the nanocrystalline-assembled bundle-like CuO is much better than that of CuO nanoparticles obtained by destroying the assembled bundle-like CuO through grinding. XRD analysis of both the electrodes after ending the discharge/charge proved that during the discharge/charge process, the conversion reactions occurring in the assembled structures have better reversibility, leading to the high rate capacity and cycling performances. The better reversibility originates from the better contact area for CuO/electrolyte, enhancing many sites to the access of Li+ in the electrolyte Li+. In addition, the assembled bundle-like CuO architectures can also relieve the volume variations during the Li+ uptake–release process, which also contributes to the excellent electrochemical performance. The high rate capacity and enhanced cycling stability of the bundle-like CuO structure make it a promising candidate as an anode material for high-performance Li-ion batteries.
Co-reporter:Xing Zhang, Zheng Xing, Lili Wang, Yongchun Zhu, Qianwen Li, Jianwen Liang, Yang Yu, Tao Huang, Kaibin Tang, Yitai Qian and Xiaoyan Shen
Journal of Materials Chemistry A 2012 vol. 22(Issue 34) pp:17864-17869
Publication Date(Web):13 Jul 2012
DOI:10.1039/C2JM32421K
MnO@C core–shell nanoplates with a size of ∼150 nm have been prepared via thermal treatment deposition of acetylene with the precursor of Mn(OH)2 nanoplates, which has been hydrothermally synthesized. The thickness of the carbon shells varied from ∼3.1 to 13.7 nm by controlling the treatment temperature and reaction duration time. The electrochemical performance of the MnO@C nanoplates, which were synthesized at 550 °C for 10 h with a carbon shell thickness of ∼8.1 nm, display a high reversible capacity of ∼770 mA h g−1 at a current density of 200 mA g−1 and good cyclability after prolonged testing, which is higher than that of MnO@C nanoplates with a carbon shell thickness of ∼3.1, 4.0, 4.2, 10.9 and 13.7 nm.
Co-reporter:Linlin Wang, Huaxu Gong, Caihua Wang, Dake Wang, Kaibin Tang and Yitai Qian
Nanoscale 2012 vol. 4(Issue 21) pp:6850-6855
Publication Date(Web):24 Aug 2012
DOI:10.1039/C2NR31898A
Various CuO nanostructures have been well studied as anode materials for lithium ion batteries (LIBs); however, there are few reports on the synthesis of porous CuO nanostructures used for anode materials, especially one-dimensional (1D) porous CuO. In this work, novel 1D highly porous CuO nanorods with tunable porous size were synthesized in large-quantities by a new, friendly, but very simple approach. We found that the pore size could be controlled by adjusting the sintering temperature in the calcination process. With the rising of calcination temperature, the pore size of CuO has been tuned in the range of ∼0.4 nm to 22 nm. The porous CuO materials have been applied as anode materials in LIBs and the effects of porous size on the electrochemical properties were observed. The highly porous CuO nanorods with porous size in the range of ∼6 nm to 22 nm yielded excellent high specific capacity, good cycling stability, and high rate performance, superior to that of most reported CuO nanocomposites. The CuO material delivers a high reversible capacity of 654 mA h g−1 and 93% capacity retention over 200 cycles at a rate of 0.5 C. It also exhibits excellent high rate capacity of 410 mA h g−1 even at 6 C. These results suggest that the facile synthetic method of producing a tunable highly porous CuO nanostructure can realize a long cycle life with high reversible capacity, which is suitable for next-generation high-performance LIBs.
Co-reporter:Yang Yu, Yongchun Zhu, Huaxu Gong, Yanmei Ma, Xing Zhang, Na Li, Yitai Qian
Electrochimica Acta 2012 Volume 83() pp:53-58
Publication Date(Web):30 November 2012
DOI:10.1016/j.electacta.2012.08.003
Fe3O4/C composites have been prepared by sucrose calcining with Fe3O4 particles obtained from ferrous oxalate decomposition. The scanning electron microscopy (SEM) images show that Fe3O4 nanoparticles (Fe3O4 NPS) with average size of 200 nm are embedded in the three-dimensional (3D) carbon-framework. As an anode material for rechargeable lithium-ion batteries, the Fe3O4/C composite delivers a reversible capacity of 773 mAh g−1 at a current density of 924 mA g−1 after 200 cycles, higher than that of the bare Fe3O4 NPS which only retain a capacity of 350 mAh g−1. When the current density rises to 1848 mA g−1, Fe3O4/C material still remains 670 mAh g−1 even after 400 cycles. The enhanced high-rate performance can be attributed to the 3D carbon-framework, which improves the electric conductivity, relaxes the strain stress and prevents the aggregation of Fe3O4 particles during the charge/discharge process.Highlights► Fe3O4 nanoparticles are embedded in the three-dimensional carbon-framework. ► Carbon layers and Fe3O4 nanoparticles bulid a special micro-nanostructure. ► Carbon-framework favors fast electrons transportation during the charge/discharge process. ► Carbon-framework improves the cyclic stability of the composite. ► Fe3O4/C composite show higher capacity retention in comparison with that of Fe3O4 nanoparticles.
Co-reporter:Na Li, Tao Mei, Yongchun Zhu, Linlin Wang, Jianwen Liang, Xing Zhang, Yitai Qian and Kaibin Tang
CrystEngComm 2012 vol. 14(Issue 20) pp:6435-6440
Publication Date(Web):12 Jul 2012
DOI:10.1039/C2CE25900A
Lithium titanate oxide hydrate (Li1.81H0.19Ti2O5·xH2O) nanosheets were prepared via simple hydrothermal treatment of the low cost tetrabutyl titanate in LiOH solution. The orthorhombic Li1.81H0.19Ti2O5·xH2O nanosheets with thickness less than 10 nm were single crystalline and grew along the (100) facet. Time-dependent experiments confirmed that the formation of Li1.81H0.19Ti2O5·xH2O nanosheets underwent a hydrolysis–Kirkendall effect–Ostwald ripening process. As these Li1.81H0.19Ti2O5·xH2O nanosheets calcined at 500 °C for 2 h, the Li4Ti5O12 nanosheets with thickness of 10–20 nm were synthesized. The Li4Ti5O12 nanosheets were single crystalline and grew along the (110) facet. As an anode material for rechargeable lithium-ion batteries, Li4Ti5O12 nanosheets delivered an initial discharge capacity of 183 mAh g−1 together with a discharge capacity of 160 mAh g−1 after 100 cycles at 1 C. The discharge capacity could reach up to 120 mAh g−1 even after 300 cycles at 10 C. The morphology of nanosheets with large BET value (155.5 m2 g−1) and the high lithium-ion diffusion coefficient (1.51 × 10−8 cm2 s−1) could be favorable for the enhanced high-rate performance.
Co-reporter:Xing Zhang, Zheng Xing, Yang Yu, Qianwen Li, Kaibin Tang, Tao Huang, Yongchun Zhu, Yitai Qian and Dong Chen
CrystEngComm 2012 vol. 14(Issue 4) pp:1485-1489
Publication Date(Web):13 Dec 2011
DOI:10.1039/C1CE06289A
Mn3O4
nanowires with diameter of ∼15 nm and a length of up to several micrometres have been hydrothermally synthesized at 200 °C for 15 h without any surfactants. It was investigated that during the formation process of Mn3O4 nanowires the length of the nanowires increased while the diameter did not obviously change. The coercivity of the Mn3O4 nanowires is up to 5600 Oe at 5 K. As these Mn3O4 nanowires were treated with LiOH by solid state reaction at 750 °C for 6 h, interconnected LiMn2O4 polyhedrons were obtained. The achieved discharge capacity of the LiMn2O4 polyhedrons was 115 mAh g−1 and they retained 98.3% of this capacity after 60 cycles at 0.1 C.
Co-reporter:Tao Mei, Yongchun Zhu, Kaibin Tang and Yitai Qian
RSC Advances 2012 vol. 2(Issue 33) pp:12886-12891
Publication Date(Web):08 Oct 2012
DOI:10.1039/C2RA21392C
LiNi1/3Co1/3Mn1/3O2/carbon core–shell nanocomposites with sizes of ∼100 nm and carbon shell thicknesses of ∼6 nm are obtained by a modified Pechini process, in which LiNi1/3Co1/3Mn1/3O2 is formed synchronously with a carbon coating in the presence of polyethylene glycol-600. Electrochemical measurements show that the nanocomposites deliver a stable discharge capacity of 175 mA h g−1 at 1 C and a capacity decay rate of <3% after 100 cycles. The effects of synthesis temperature on the electrochemical performance of the nanocomposites are examined, which shows that the discharge capacities increase from 154 to 175 mA h g−1 as the temperature increases from 800 to 1000 °C. Meanwhile, the electrochemical performances of the nanocomposites with carbon content varying from 0 to 20.8% are examined. Among these composites, that with 15.5% carbon content exhibits the highest and most stable discharge behaviour at 1 C for 100 cycles.
Co-reporter:Liangbiao Wang, Qianwen Li, Tao Mei, Liang Shi, Yongchun Zhu, Yitai Qian
Materials Chemistry and Physics 2012 Volume 137(Issue 1) pp:1-4
Publication Date(Web):15 November 2012
DOI:10.1016/j.matchemphys.2012.08.008
Starting from waste polytetrafluoroethylene (PTFE), metal oxides (TiO2, V2O5, Nb2O5, and MoO3) and metal sodium, several nanocrystalline transition metal carbides (TiC, VC, NbC, and Mo2C) have been prepared through a thermal reduction route in an autoclave at 600 °C. It is found that the obtained NbC nanocrystallines have a superconducting transition temperature at 11.6 K.Highlights► NbC can be prepared from metal sodium, Nb2O5 and waste polytetrafluoroethylene. ► The obtained NbC have a superconducting transition temperature at 11.6 K. ► This route has been extended for the preparation of carbides (TiC, VC, Mo2C).
Co-reporter:Tao Mei, Jingjing Zhang, Lili Wang, Zheng Xing, Yongchun Zhu, Yitai Qian
Materials Letters 2012 Volume 82() pp:1-3
Publication Date(Web):1 September 2012
DOI:10.1016/j.matlet.2012.05.032
Ca9Co12O28 nanoparticles with size of about 25 nm were prepared by Pechini process at 850 °C for 4 h. The as-obtained nanoparticles demonstrated initial charge/discharge capacities of 908 and 816 mAh/g and a stable discharge capacity of 210 mAh/g after 50 cycles. Different morphologies of Ca9Co12O28 as multilayer structure and micro-plates were also obtained by solid-state reaction and coprecipitation-precursor technique at 850 °C for 20 h. When they were studied in the charge/discharge experiments of lithium ion batteries, the initial discharge capacities reached values of 762 and 790 mAh/g, together with stable discharge capacities of 141 and 151 mAh/g after 50 cycles, respectively, which were both lower than those of nanoparticles.Graphical abstractHighlights► Ca9Co12O28 nanoparticles (25 nm) were rapidly prepared by Pechini process. ► Ca9Co12O28 multilayer structures were obtained by solid-state reaction. ► Ca9Co12O28 micro-plates were prepared by coprecipitation-precursor technique. ► The electrochemical performances of Ca9Co12O28 were firstly researched. ► The capacities and cyclical stabilities of different morphologies were compared.
Co-reporter:Tao Mei, Na Li, Qianwen Li, Zheng Xing, Kaibin Tang, Yongchun Zhu, Yitai Qian, Xiaoyan Shen
Materials Research Bulletin 2012 47(6) pp: 1604-1608
Publication Date(Web):
DOI:10.1016/j.materresbull.2012.03.011
Co-reporter:Yongchun Zhu, Tao Mei, Yan Wang and Yitai Qian
Journal of Materials Chemistry A 2011 vol. 21(Issue 31) pp:11457-11463
Publication Date(Web):22 Jun 2011
DOI:10.1039/C1JM11079A
Formation and morphology control of nanomaterials is a crucial issue in nanoscience research in the exploitation of novel properties. This article presents a review of some research activities on the formation and morphology control of nanoparticlesvia solution routes in an autoclave over the last decade. Several solution systems, including hydrothermal, solvothermal and mixed solvothermal routes, are specifically discussed and highlighted. A helical belt template mechanism was proposed for the formation of the Te nanotubes in aqueous ammonia. Assisted by the surfactant of sodium dodecyl benzenesulfonate (SDBS), nickel nanobelts were hydrothermally synthesized. Ethylenediamine (En) and n-butylamine can be used as shape controllers to one-dimensional (1D) semiconductor nanostructures in the solvothermal process. The phase of metastable and stable MnS crystallites can be controlled by solvothermal reaction in various solvents. Selective preparation of 1D to 3D CdS nanostructures was achieved by controlling the volume ratio of the mixed solvents. With poly(vinylpyrrolidone) (PVP) serving as a soft template, the transformation from nanowires to nanotubes, then to nanowires was observed in the mixed solvents of distilled water and ethanolamine (EA).
Co-reporter:Yongchun Zhu, Qianwen Li, Tao Mei and Yitai Qian
Journal of Materials Chemistry A 2011 vol. 21(Issue 36) pp:13756-13764
Publication Date(Web):21 Jul 2011
DOI:10.1039/C1JM11893E
This feature article provides a brief overview of the latest developments in the solid state synthesis of various nitride, carbide and boride nanocrystals in an autoclave at mild temperatures. An additive assisted route was developed for nitride, carbide and boride nanocrystals. In the presence of S powder, 3C–SiC nanocrystals were obtained utilizing waste plastics and Si powder at 350–500 °C. With the assistance of I2, rare-earth and alkaline-earth hexaboride nanocrystals were prepared at temperatures below 400 °C. As N-aminothiourea and iodine were added to the system containing Si and NaN3, β-Si3N4 nanorods and α,β-Si3N4 nanoparticles could be prepared at 60 °C. A ternary nitride of MgSiN2 can also be prepared at 350–500 °C using Si, Mg, and NaN3 as reactants.
Co-reporter:Tao Mei, Kaibin Tang, Yongchun Zhu and Yitai Qian
Dalton Transactions 2011 vol. 40(Issue 29) pp:7645-7650
Publication Date(Web):24 Jun 2011
DOI:10.1039/C1DT10228A
LiCoO2 concaved cuboctahedra with a size of about 1.0 μm were hydrothermally prepared from CoCO3 and LiOH·H2O at 150 °C. Field-emitting scanning electron microscope (FESEM) images show that the cuboctahedra consisted of four hexagonal plates, with angles of 70.5° in neighboring plates. Electron diffraction (ED) patterns of the hexagonal plates show 100 diffraction of LiCoO2 in rhombohedral phase and 220 diffraction in spinel phase, which means LiCoO2 concaved cuboctahedra are comprised of two intergrown phases. The electrochemical performance of these concaved cuboctahedra of LiCoO2 at a rate of 0.5 C demonstrated first run charge/discharge capacities of 155 and 141 mAh g−1 and a stable discharge capacity of 114 mAh g−1 after 100 cycles. After that, FESEM images show the LiCoO2 concaved cuboctahedra have undergone no significant change. At a temperature of 120 °C and under the same conditions, only a small amount of LiCoO2 concaved cuboctahedron appeared. As the temperature rose to 180 °C, flower-like LiCoO2 microstructures with a size of about 1.0 μm were formed, constructed of irregular plates. The electrochemical performance of the products prepared at 120 °C and 180 °C indicates lower stability than that of LiCoO2 concaved cuboctahedra.
Co-reporter:Qianwen Li, Liangbiao Wang, Yongchun Zhu, Yitai Qian
Materials Letters 2011 Volume 65(15–16) pp:2410-2412
Publication Date(Web):August 2011
DOI:10.1016/j.matlet.2011.04.102
Graphene nanosheets (GS) had been solvothermally synthesized through reducing hexachloro-1,3-butadiene (C4Cl6) by metallic sodium (Na) in polyethylene glycol-600 (PEG-600) at 300 °C. Atomic force microscopy (AFM) and high-resolution transmission electron microscopy (HRTEM) investigations indicated that 1–3 graphite layers could be observed. The Raman spectrum showed that the peak of 2D band at 2693 cm− 1 of GS had a smaller wave number and stronger intensity compared to the 2717 cm− 1 of commercial graphitic flakes. Meanwhile, the ID/IG value of GS was 0.40 indicating a lower density of defects of GS. The possible reaction process was that C4Cl6 was dechlorinated by Na in the presence of PEG-600 to produce carbon framework, then these newly produced carbon framework would connect to each other to form the hexagonal network of graphene.Research Highlights► GS had been synthesized through reducing C4Cl6 by Na in PEG-600 at 300 °C. ► AFM and HRTEM indicated 1~3 graphite layers could be observed. ► Raman showed the peak of 2D band had a red shift compared to the bulk graphite. ► The ID/IG value of GS was 0.4, indicating a low number of defects.
Co-reporter:Wenjun Kang ; Haibo Li ; Yan Yan ; Peipei Xiao ; Lingling Zhu ; Kaibin Tang ; Yongchun Zhu
The Journal of Physical Chemistry C 2011 Volume 115(Issue 14) pp:6250-6256
Publication Date(Web):March 23, 2011
DOI:10.1021/jp111702s
Worm-like palladium/carbon (Pd/C) core−shell nanocomposites have been hydrothermally prepared starting from PdCl2 and α-lactose monohydrate (α-LM) in the presence of polyacrylamide (PAM) at 200 °C. The thickness of carbonaceous shells varied from 5 to 45 nm with increasing temperature from 140 to 200 °C. When the dose of PAM or PdCl2 was increased, spherical Pd/C core−shell nanocomposites were obtained. Time-dependent experiments confirmed that formation of Pd/C core−shell nanocomposites underwent an entrapment−reduction−carbonization process. Such a route has also been extended to synthesize spherical Ag/C core−shell composites. A cyclic voltammetry (CV) study reveals that the as-prepared Pd/C core−shell nanocomposites exhibit electrocatalytic activity toward oxidation of ascorbic acid (AA).
Co-reporter:Zhaoping Liu;Xufeng Zhou
Advanced Materials 2010 Volume 22( Issue 17) pp:1963-1966
Publication Date(Web):
DOI:10.1002/adma.200903813
Abstract
Carbon nanomaterials have advanced rapidly over the last two decades and are among the most promising materials that have already changed and will keep on changing human life. Development of synthetic methodologies for these materials, therefore, has been one of the most important subjects of carbon nanoscience and nanotechnology, and forms the basis for investigating the physicochemical properties and applications of carbon nanomaterials. In this Research News article, several synthetic strategies, including solvothermal reduction, solvothermal pyrolysis, hydrothermal carbonization, and soft-chemical exfoliation are specifically discussed and highlighted, which have been developed for the synthesis of novel carbon nanomaterials over the last decade.
Co-reporter:Haibo Li, Wenjun Kang, Baojuan Xi, Yan Yan, Huiyun Bi, Yongchun Zhu, Yitai Qian
Carbon 2010 Volume 48(Issue 2) pp:464-469
Publication Date(Web):February 2010
DOI:10.1016/j.carbon.2009.09.063
A Cu@carbon (Cu@C) spherical core–shell structure has been synthesized from carbonaceous matrices containing embedded copper particles by thermal treatment at 600 °C under an argon atmosphere. The matrices are prepared by reducing CuCl2 with vitamin C (VC) in the existence of polyacrylamide (PAM) at 180 °C, accompanied by the partial carbonization of VC. It is found that small Cu nanoparticles with diameters of ∼3 nm homogeneously disperse in the carbonaceous matrices. Subsequent thermal treatment at 600 °C under an argon atmosphere leads to the diffusion of these Cu nanoparticles and further carbonization of carbonaceous matrices to form a Cu@C core–shell structure. The core–shell ratio can be controlled by varying the dose of CuCl2, VC, or PAM. It is found that the carbon shell can effectively shield the metallic Cu core from oxidation in the mixed solution of dilute hydrogen peroxide and nitric acid.
Co-reporter:Tao Mei;Ting Li;Huiyun Bi;Liangbiao Wang;Yongchun Zhu
European Journal of Inorganic Chemistry 2010 Volume 2010( Issue 27) pp:4314-4320
Publication Date(Web):
DOI:10.1002/ejic.201000387
Abstract
Carbon nanoplates with diameters and thicknesses of up to approximately 1.2 μm and 18 nm, respectively, were prepared by a reaction using CaC2, ferrocene, and NH4HCO3 as starting materials at 600 °C for 10 h. These carbon nanoplates form aggregates that have a specific surface area of up to 831 m2 g–1 and a specific capacitance of up to 184 F g–1 at a scanning rate of 10 mV s–1 in a 3 mol L–1 H2SO4 solution. Without using NH4HCO3, hexagonal carbon nanoplates with an average edge length of 500 nm and thickness of approximately 22 nm were obtained with a specific capacitance of up to 42 F g–1. If NaN3 or NaHCO3 was used instead of NH4HCO3, carbon nanoplates with a curved surface or irregular circular carbon nanoplates were obtained with specific capacitances of 87 or 36 F g–1, respectively.
Co-reporter:Maofeng Zhang;Ying Jia;Guogen Xu;Pengfei Wang;Xiaoqing Wang;Shenglin Xiong;Xuanjun Wang
European Journal of Inorganic Chemistry 2010 Volume 2010( Issue 8) pp:1289-1294
Publication Date(Web):
DOI:10.1002/ejic.200901015
Abstract
Submicron crystalline rare-earth hexaborides (RB6; R = Sm, Eu, Gd, and Tb) have been successfully prepared by a facile one-step solid-state reaction of RCl3·6H2O, B2O3, and Mg powder in an autoclave at the relatively low temperature of 500 °C. By controlling the reaction conditions, submicron-sized cubes (RB6) and rod- and needlelike SmB6 are obtained. The possible growth mechanism of the 1D SmB6 structures has also been discussed. The XRD patterns of the products show that all of the hexaborides can be indexed to a cubic phase with high crystallinity and high purity. The field-emission scanning electron microscopy (FESEM) and TEM images display their cube-, rod-, and needlelike morphologies. The selected-area electron diffraction (SAED) patterns reveal the single-crystalline nature of the products.
Co-reporter:Jie Cao;Yongchun Zhu;Liang Shi;Lingling Zhu;Keyan Bao;Shuzhen Liu
European Journal of Inorganic Chemistry 2010 Volume 2010( Issue 8) pp:1172-1176
Publication Date(Web):
DOI:10.1002/ejic.200901116
Abstract
Double-shelled Mn2O3 hollow spheres have been successfully prepared on a large scale by using core-shell-structured MnCO3 microspheres as sacrificial templates. This new method is based on an inward oxidation/etching treatment and sequential heat treatment in air. The as-prepared double-shelled Mn2O3 hollow spheres consist of small nanoparticles with a size of ca. 50 nm, and there are many nanopores among the particles. As the double-shelled Mn2O3 hollow spheres were employed in water treatment, they could remove about 86 % of phenol without any other additives.
Co-reporter:Jun Gu, Yongchun Zhu, Haibo Li, Shenglin Xiong, Xianwen Zhang, Xiaoqing Wang, Xiaoyan Liu, Yitai Qian
Solid State Sciences 2010 Volume 12(Issue 7) pp:1192-1198
Publication Date(Web):July 2010
DOI:10.1016/j.solidstatesciences.2010.03.015
NaLa(WO4)2:Eu microcrystals with shapes of four-arris shuttle, quadrangled star, and quadrangled dendrite were hydrothermally synthesized at 180 °C for 16 h. The concentration of the reactants and cetyltrimethyl ammonium bromide (CTAB) influenced the morphologies of the products. As La(NO3)3, Na2WO4 and CTAB was 0.375, 1.0, and 1.0 mmol, respectively, four-arris shuttle was obtained. As the concentration of the reactants doubled and the amount of CTAB ranged from 0.4 to 2.0 mmol, quadrangled dendrite, quadrangled star and four-arris shuttle were prepared, respectively. Luminescence intensity measurement of the three morphologies of NaLa(WO4)2:Eu showed that quadrangled dendrite was the strongest and four-arris shuttle was the lowest.
Co-reporter:Jun Gu, Yongchun Zhu, Haibo Li, Xianwen Zhang, Yitai Qian
Journal of Solid State Chemistry 2010 Volume 183(Issue 3) pp:497-503
Publication Date(Web):March 2010
DOI:10.1016/j.jssc.2009.12.019
Uniform shuttle-like Ln3+ (Eu3+, Tb3+) doped NaLa(WO4)2 nanocrystals have been solvothermally synthesized, and the size of the nanocrystals could be easily controlled by adjusting the volume ratio of ethylene glycol (EG) to water. Doped with 5 mol% Eu3+ and Tb3+ ions, the NaLa(WO4)2 nanocrystals showed strong red and green emissions with lifetimes of 0.8 and 1.40 ms, respectively. A high quenching concentration of 15 mol% was observed in Eu3+-doped NaLa(WO4)2 nanocrystals and 35 mol% in Tb3+-doped NaLa(WO4)2 nanocrystals. The emission intensity measurements of Eu3+-doped NaLa(WO4)2 with different sizes indicated that the emission intensity of shuttles with length of 300 nm in average was stronger than that of shuttles with length of 900 nm in average, but was weaker than that of needles with length of 4 and 9 μm in average.Uniform shuttle-like Ln3+(Eu3+, Tb3+) doped NaLa(WO4)2 nanocrystals have been solvothermally synthesized in the mixed solvent of ethylene glycol (EG) and water at 180 °C for 16 h.
Co-reporter:Tingting Wang, Junli Wang, Yongchun Zhu, Fei Xue, Jie Cao, Yitai Qian
Journal of Physics and Chemistry of Solids 2010 Volume 71(Issue 7) pp:940-945
Publication Date(Web):July 2010
DOI:10.1016/j.jpcs.2010.04.001
Zinc blende (ZB) CdSe hollow nanospheres were solvothermally synthesized from the reaction of Cd(NO3)2·4H2O with a homogeneously secondary Se source, which was first prepared by dissolving Se powder in the mixture of ethanol and oleic acid at 205 °C. As Se power directly reacted with Cd(NO3)2·4H2O in the above mixed solvents, wurtzite (W) CdSe solid nanoparticles were produced. Time-dependent experiments suggested that the formation of CdSe hollow nanospheres was attributed to an inside-out Ostwald ripening process. The influences of reaction time, temperature and ethanol/oleic acid volume ratio on the morphology, phase and size of the hollow nanospheres were also studied. Infrared (IR) spectroscopy investigations revealed that oleic acid with long alkene chains behaved as a reducing agent to reduce Se powder to Se2− in the synthesis. Photoluminescence (PL) measurements showed that the ZB CdSe hollow nanospheres presented an obvious blue-shifted emission by 42 nm, and the W CdSe solid nanoparticles exhibited a band gap emission of bulk counterpart.
Co-reporter:Lili Wang, Yongchun Zhu, Haibo Li, Qianwen Li, Yitai Qian
Journal of Solid State Chemistry 2010 Volume 183(Issue 1) pp:223-227
Publication Date(Web):January 2010
DOI:10.1016/j.jssc.2009.10.021
NiS nanobelts of hexagonal phase have been hydrothermally synthesized starting from Ni(CH3COO)2·4H2O and Na2S2O3·5H2O at 200 °C for 12 h. The as-prepared nanobelts were 50 nm thick, 70–200 nm wide and more than 10 μm long. As ethylenediaminetetraacetic acid (EDTA) added, in similar condition, 2 μm NiS2 microspheres of cubic phase were prepared. However, as Ni2+/S2O32- ratio was 1:1 and the temperature was decreased to 160 °C, 5 μm NiS2 microspheres constructed of cuboids were formed.Hexagonal NiS nanobelts and cubic NiS2 microspheres were hydrothermally synthesized in the reaction of Ni(CH3COO)2·4H2O and Na2S2O3·5H2O.
Co-reporter:Xianwen Zhang, Maofeng Zhang, Yongchun Zhu, Pengfei Wang, Fei Xue, Jun Gu, Huiyun Bi, Yitai Qian
Materials Research Bulletin 2010 45(9) pp: 1324-1329
Publication Date(Web):
DOI:10.1016/j.materresbull.2010.04.022
Co-reporter:Haibo Li, Yongchun Zhu, Zhenghao Mao, Jun Gu, Junhao Zhang, Yitai Qian
Carbon 2009 Volume 47(Issue 1) pp:328-330
Publication Date(Web):January 2009
DOI:10.1016/j.carbon.2008.09.053
Carbon fibrils with length of 2–3 μm formed by stacking graphite sheets of ∼10–40 nm in thickness along the 〈0 0 1〉 direction were prepared by pyrolysis of tetrahydrofuran at 600 °C in the existence of metallic nickel. The spacing of adjacent sheets concentrated on ∼3.8 nm and ∼50 nm. Metallic nickel played a catalytic role in the formation of carbon fibrils, and a possible formation process was proposed.
Co-reporter:Hongyang Zhou, Shenglin Xiong, Lingzhi Wei, Baojuan Xi, Yongchun Zhu and Yitai Qian
Crystal Growth & Design 2009 Volume 9(Issue 9) pp:3862-3867
Publication Date(Web):July 7, 2009
DOI:10.1021/cg801405e
Uniform 5 μm Bi2S3 microspheres and 8 μm microflowers were solvothermally synthesized in acetylacetone solution through thermolysis of the Bi3+-dithizone complex without any templates or surfactants. Bi2S3 microspheres composed of nanorods with a diameter of 20−40 nm were synthesized at 180 °C for 12 h. In similar conditions at 240 °C for 3 days, microflowers composed of nanowires with lengths up to several micrometers and diameter of 20−40 nm were obtained. Field-emission scanning electron microscopy (FESEM) showed in the initial stage in the formation process that smooth spherical cores were observed, then on the surface of the cores nanoparticles appeared, and finally nanorods or nanowires grew out and microspheres and microflowers formed. Electrochemical experiments using Bi2S3 in a lithium ion battery indicated that the first discharge capacity of Bi2S3 microflowers could reach about 148 mA h g−1.
Co-reporter:Jun Pan;Shenglin Xiong;Baojuan Xi;Jiangfa Li;Jiangying Li;Hongyang Zhou
European Journal of Inorganic Chemistry 2009 Volume 2009( Issue 35) pp:
Publication Date(Web):
DOI:10.1002/ejic.200900607
Abstract
Alveolate amorphous Sb2S3 microspheres about 2 μm in diameter were hydrothermally synthesized in aqueous solution without the use of a surfactant at 180 °C by using SbCl3, L-cysteine, and tartaric acid as starting materials. After annealing at 250 °C for 3 h under a nitrogen atmosphere, polycrystalline Sb2S3 hollow spheres were obtained. The morphology, structure, and phase composition of alveolate Sb2S3 microspheres were characterized by X-ray diffraction, field-emission scanning electron microscopy, energy dispersive X-ray analysis, and X-ray photoelectron spectroscopy. It was demonstrated that tartaric acid and L-cysteine play a key role in the formation of such hierarchical structures. In addition, the possible aggregation mechanism was proposed to illustrate the formation of Sb2S3 microspheres on the basis of the experimental results and analyses.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Co-reporter:Xiaoyan Liu, Renzhi Hu, Shenglin Xiong, Yankuan Liu, Lanlan Chai, Keyan Bao, Yitai Qian
Materials Chemistry and Physics 2009 Volume 114(Issue 1) pp:213-216
Publication Date(Web):15 March 2009
DOI:10.1016/j.matchemphys.2008.09.009
Co-reporter:Maofeng Zhang, Xiaoqing Wang, Xianwen Zhang, Pengfei Wang, Shenglin Xiong, Liang Shi, Yitai Qian
Journal of Solid State Chemistry 2009 Volume 182(Issue 11) pp:3098-3104
Publication Date(Web):November 2009
DOI:10.1016/j.jssc.2009.08.032
Co-reporter:Fei Xue, Haibo Li, Yongchun Zhu, Shenglin Xiong, Xianwen Zhang, Tingting Wang, Xin Liang, Yitai Qian
Journal of Solid State Chemistry 2009 Volume 182(Issue 6) pp:1396-1400
Publication Date(Web):June 2009
DOI:10.1016/j.jssc.2009.02.031
Hexagonal phase BiPO4 nano-cocoons and monoclinic phase BiPO4 nanorods have been synthesized in the mixed solvents of glycerol and distilled water with the volume ratio of 2:1 at 200 °C. The solvothermal evolution process from hexagonal phase BiPO4 nano-cocoons to monoclinic phase BiPO4 nanorods was observed by varying the reaction time from 1 to 3 h. In the hydrothermal condition at 160 °C, the similar phase transformation from hexagonal phase BiPO4 to monoclinic phase BiPO4 was also observed, accompanying with a morphology transformation from nanorods to octahedron-like microcrystals. It was found that the volume ratio of glycerol to water in the solvothermal condition had a great impact on the shapes of products, while it had no influence on the formation of different phases. The fluorescence spectra of hexagonal phase BiPO4 nano-cocoons and monoclinic phase BiPO4 nanorods were also studied.Hexagonal phase BiPO4 nano-cocoons were fabricated by solvothermal method at 200 °C for 1 h. When the reaction time was increased to 3 h, monoclinic phase BiPO4 nanorods were formed.
Co-reporter:Keyan Bao, Fengyang Yu, Liang Shi, Shuzhen Liu, Xiaobo Hu, Jie Cao, Yitai Qian
Journal of Solid State Chemistry 2009 Volume 182(Issue 4) pp:925-931
Publication Date(Web):April 2009
DOI:10.1016/j.jssc.2009.01.004
Highly crystalline rhombohedral boron nitride (r-BN) with regular triangular shapes were synthesized on a large scale in a stainless steel autoclave using B2O3 and NaNH2 as reactants at 600 °C for 6 h. The as-prepared BN triangular nanoplates have an average edge length of 400 nm and the thickness of about 60 nm. The photoluminescence measurements reveal that the r-BN products show strong yellow-green emission. The as-prepared r-BN has potential optical and optoelectronic applications in high temperature devices due to its excellent thermal stability and anti-oxidation properties.Rhombohedral BN triangular nanoplates were synthesized at 600 °C. The products exhibit excellent luminescence, thermal stability and anti-oxidation properties; they are expected to become good candidates for optical and optoelectronic devices.
Co-reporter:Yankuan Liu, Han Wang, Yongchun Zhu, Xiaoqing Wang, Xiaoyan Liu, Haibo Li, Yitai Qian
Solid State Communications 2009 Volume 149(37–38) pp:1514-1518
Publication Date(Web):October 2009
DOI:10.1016/j.ssc.2009.06.008
The concentration of the Mn(NO3)2 solution has significant influence on the morphologies and the phases of the MnO2 products. A large number of εε- MnO2 nanowires were prepared via a simple pyrolysis under lower reaction concentration. The nanowires have lengths up to tens of micrometers and diameters in the range of 20–100 nm. The ββ- MnO2 nanobundles and nanoflowers were prepared by increasing the concentration of Mn(NO3)2 solution. The superparamagnetism of εε- MnO2 nanowires and paramagnetism of ββ- MnO2 nanoflowers indicate their potential applications in magnetic materials.
Co-reporter:Xiaoqing Wang, Maofeng Zhang, Jinyun Liu, Tao Luo, Yitai Qian
Sensors and Actuators B: Chemical 2009 Volume 137(Issue 1) pp:103-110
Publication Date(Web):28 March 2009
DOI:10.1016/j.snb.2008.11.027
Hexagonal In2O3 microspheres, cubic In2O3 porous nanoparticles, and cubic In2O3 porous nanorectangles were fabricated by calcining precursors at 450 °C, respectively. The precursors InOOH microspheres, In(OH)3 nanoparticles, and In(OH)3 nanorectangles were solvothermally synthesized by adjusting the volume ratios of ethylenediamine and distilled water in autoclave at 160 °C. Gas-sensing properties determination of ethanol, formaldehyde, and ammonia gases show that the cubic In2O3 porous nanoparticles have a higher response than the hexagonal In2O3 microspheres.
Co-reporter:Xin Liang, Baojuan Xi, Shenglin Xiong, Yongchun Zhu, Fei Xue, Yitai Qian
Materials Research Bulletin 2009 44(12) pp: 2233-2239
Publication Date(Web):
DOI:10.1016/j.materresbull.2009.08.003
Co-reporter:Shenglin Xiong Dr.;Changzhou Yuan Dr.;Xiaogang Zhang ;Baojuan Xi Dr.
Chemistry - A European Journal 2009 Volume 15( Issue 21) pp:5320-5326
Publication Date(Web):
DOI:10.1002/chem.200802671
Co-reporter:Jie Cao, Yongchun Zhu, Keyan Bao, Liang Shi, Shuzhen Liu and Yitai Qian
The Journal of Physical Chemistry C 2009 Volume 113(Issue 41) pp:17755-17760
Publication Date(Web):September 16, 2009
DOI:10.1021/jp905482z
Various Mn2O3 hollow structures, such as spheres, cubes, ellipsoids, and dumbbells have been synthesized through the following process: The surfaces of the prepared MnCO3 microspheres, microcubes, and microellipsoids were oxidized by KMnO4 to form a core/shell structure. Similarly, the surface of a dumbbell-like MnCO3 intermediate can also be oxidized by KMnO4. As the MnCO3 or MnCO3 intermediate cores were dissolved by acid, the MnO2 shells were formed. Calcining these MnO2 shells at 500 °C, polycrystalline Mn2O3 hollow structures were obtained. The morphologies of these hollow structures were similar to their precursors. The as-prepared hollow Mn2O3 materials were used as adsorbents in water treatment, and the hollow Mn2O3 spheres, cubes, ellipsoids, and dumbbells could respectively remove about 77%, 83%, 81%, and 78% of phenol.
Co-reporter:Shuzhen Liu, Shenglin Xiong, Keyan Bao, Jie Cao and Yitai Qian
The Journal of Physical Chemistry C 2009 Volume 113(Issue 30) pp:13002-13007
Publication Date(Web):July 1, 2009
DOI:10.1021/jp8104437
PbS fishbone-like architectures were synthesized by using a biomolecule (l-methionine)-assisted approach in a mixture solvent made of ethanolamine (EA) and distilled water. Additionally, other PbS homogeneous morphologies (e.g., hexapod-like, coralloid, and dendritic) were obtained through altering the experimental parameters, such as the molar ratio of the reactants and the volume ratio of the mixture solvent. It is noteworthy that our experiments were envionmentally friendly, because no disgusting scent (H2S) appeared in our experiments, which could be hardly avoided in other previous reports. The as-prepared PbS products were examined by using XRD, FESEM, TEM, HRTEM, SAED, and PL. Furthermore, a possible growth mechanism (an initial nucleating stage and a subsequent growth stage) was proposed to explain the formation of dendritic architectures on the basis of TEM observations, XRD, and FTIR analyses. Up to now, this is the first case of the direct growth of novel PbS with various hierarchical nanostructures with l-methionine’s assistance. The synthesized PbS fishbone-like structure was found to indicate strong photoluminescence in the blue-light range.
Co-reporter:Hai Fan, Yuanguang Zhang, Maofeng Zhang, Xuyang Wang and Yitai Qian
Crystal Growth & Design 2008 Volume 8(Issue 8) pp:2838
Publication Date(Web):July 3, 2008
DOI:10.1021/cg7011364
In this study, a glucose-assisted method has been developed to prepare CoTe nanotubes using Te nanorods as the in situ templates under hydrothermal conditions. It was found that the concentration of glucose has an important influence on the morphology of the products. The average inner diameter of CoTe nanotubes can be adjusted from 60 to 20 nm by changing the quantity of glucose from 0.5 to 1.0 g. The samples are characterized by means of X-ray power diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectra (XPS), selected area electron diffraction (SAED), and transmission electron microscopy (TEM). The formation mechanism of the CoTe nanotubes is discussed based on the experimental results.
Co-reporter:Xiaoqing Wang, Guangcheng Xi, Yankuan Liu and Yitai Qian
Crystal Growth & Design 2008 Volume 8(Issue 4) pp:1406-1411
Publication Date(Web):March 12, 2008
DOI:10.1021/cg070415x
Octopod-like PbSe structures with eight symmetric arms of 1.0−3.0 µm in length have been hydrothermally synthesized without any surfactant. Keeping the other conditions the same, only by changing the molar ratio of NaOH/Pb(NO3)2 from 40 to 5, quasi-spherical nanoparticles were obtained. As poly(vinyl pyrrolidone) (PVP) was added, single-crystal PbSe nanosheets of 20−60 nm in thickness and 0.5−5.0 µm in-plane sizes can be formed. Similarly, by changing the molar ratio of NaOH/Pb(NO3)2 from 40 to 5, the nanocubes of ∼70 nm in edge length were formed. The possible growth mechanisms for the nanosheets and octopod-like structures of PbSe are discussed on the basis of transmission electron microscopy and scanning electron microscopy analysis from the time-dependent experiments.
Co-reporter:Maofeng Zhang, Liang Yuan, Xiaoqing Wang, Hai Fan, Xuyang Wang, Xueying Wu, Haizhen Wang, Yitai Qian
Journal of Solid State Chemistry 2008 Volume 181(Issue 2) pp:294-297
Publication Date(Web):February 2008
DOI:10.1016/j.jssc.2007.12.011
Nanocrystalline lanthanum hexaboride (LaB6) with mean particle size of 30 nm has been successfully synthesized at 400 °C in an autoclave starting from metallic magnesium powder, NaBH4 and LaCl3. In this case, by using B2O3 instead of NaBH4, LaB6 nanocubes with mean size of ∼200 nm were formed at 500 °C. The X-ray diffraction (XRD) pattern can be indexed as cubic LaB6 with the lattice constant of a=4.151 Å for LaB6 nanoparticles and 4.154 Å for LaB6 nanocubes. An atomic ratio of La and B as 1:5.94 was determined from EDS for LaB6 nanoparticles. XPS data of LaB6 nanocubes indicate the atomic ratio of La to B as 1:5.95. Raman spectra indicate the formation of LaB6.Nanocrystalline lanthanum hexaboride (LaB6) with mean particle size of 30 nm has been successfully synthesized at 400 °C in an autoclave starting from NaBH4, LaCl3 and metallic magnesium powder. In this case, by using B2O3 instead of NaBH4, LaB6 nanocubes with mean size of ∼200 nm were formed at 500 °C. In comparison with previous routes, the present route allows for the formation of nanocrystalline LaB6 through a simpler process and at a much lower synthesis temperature.Figure optionsDownload full-size imageDownload as PowerPoint slide
Co-reporter:Junhao Zhang, Ju Li, Jie Cao, Yitai Qian
Materials Letters 2008 Volume 62(12–13) pp:1839-1842
Publication Date(Web):30 April 2008
DOI:10.1016/j.matlet.2007.10.015
Carbon nanotubes with larger diameter of about 160 nm have been synthesized through catalytic decomposition of polypropylene and maleated polypropylene using Ni as catalysts in autoclave at 700 °C. Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM) and high-resolution transmission electron microscope (HRTEM) images reveal the morphologies and structures of carbon nanotubes. The possible growth process of carbon nanotubes was also discussed. The results indicate that reaction temperature, maleated polypropylene and Ni catalysts play key roles in the synthesis of large diameters carbon nanotubes. Also, using waste polypropylene as starting material for preparing carbon nanotubes is feasible.
Co-reporter:Jun Li, Junhao Zhang, Yitai Qian
Solid State Sciences 2008 Volume 10(Issue 11) pp:1549-1555
Publication Date(Web):November 2008
DOI:10.1016/j.solidstatesciences.2008.03.026
Bundle-like nanostructures have been synthesized via a hydrothermal treatment with the assistance of cetyltrimethylammonium bromide (CTAB). The as-synthesized bundle-like nanostructures are composed of well-aligned tellurium (Te) nanorods with lengths of 500 nm and diameters ranging from 30 to 50 nm. The formation mechanism of the Te nanostructures has been investigated and discussed. The concentration of CTAB and hydrothermal treatment temperature played crucial roles, and could be used as the parameters to control morphology of the bundle-like nanostructures. Moreover, the photoluminescence properties of the bundle-like Te nanostructures have also been studied.Bundle-like nanostructures with well-aligned Te nanorods have been synthesized on a large scale via a simple hydrothermal approach assisted by cetyltrimethylammonium bromide (CTAB). The lengths of the bundle-like Te nanostructures are about 500 nm, and the widths of these bundles are ranging from several hundred nanometers to several micrometers.
Co-reporter:Hai Fan, Jianbo Liang, Yuanguang Zhang, Maofeng Zhang, Baojuan Xi, Xuyang Wang, Yitai Qian
Solid State Sciences 2008 Volume 10(Issue 7) pp:901-907
Publication Date(Web):July 2008
DOI:10.1016/j.solidstatesciences.2007.10.008
The phase transition of CdSe nanocrystallines from zinc blende to wurtzite phase can be controlled by varying the volume ratio of ethanolamine (EA) and water (WA) in their mixed solution and the morphologies of the CdSe nanocrystals are controlled simultaneously. The phase transition has been demonstrated by XRD patterns and HRTEM images. The samples are investigated by Raman spectrum. The Raman shifts of the samples show a gradual blue shift with the gradual transformation from zinc blende to wurtzite CdSe phase. This method is convenient and controllable which can provide a strategy way to control the phase and morphology of the nanomaterials and study their phase transitions in nanoscale field.The phase transition of CdSe nanocrystals from zinc blende to wurtzite phase could be controlled by varying the volume ratio of ethanolamine and water in their mixed solution. Zinc blend CdSe nanocrystals would gradually transform into wurtzite CdSe nanocrystals with the decrease of the volume ratio of EA and WA.
Co-reporter:Keyan Bao, Shuzhen Liu, Liang Shi, Shenglin Xiong, Jun Li, Xiaobo Hu, Jie Cao, Yitai Qian
Journal of Solid State Chemistry 2008 Volume 181(Issue 7) pp:1634-1641
Publication Date(Web):July 2008
DOI:10.1016/j.jssc.2008.06.002
Co-reporter:Haizhen Wang, Jianbo Liang, Hai Fan, Baojuan Xi, Maofeng Zhang, Shenglin Xiong, Yongchun Zhu, Yitai Qian
Journal of Solid State Chemistry 2008 Volume 181(Issue 1) pp:122-129
Publication Date(Web):January 2008
DOI:10.1016/j.jssc.2007.11.010
SnO2 urchin-like structures composed of nanorods with diameters of 10–15 nm and lengths of 50–70 nm have been hydrothermally synthesized via a H2O2-assisted route without any surfactant, using SnCl2 as raw material. With the addition of methenamine (HMT), SnO2 hollow microspheres with diameters of 2–3 μm and shell thickness of 60–140 nm were also prepared. The as-obtained products were examined using diverse techniques including X-ray powder diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), high-resolution TEM and photoluminescence spectra. The gas sensitivity experiments have demonstrated that the as-synthesized SnO2 materials exhibit good sensitivity to alcohol vapors, which may offer potential applications in gas sensors.SnO2 urchin-like structures composed of short nanorods with diameter of 10–15 nm and length of 50–70 nm and SnO2 hollow microspheres have been synthesized via a simple H2O2-assisted hydrothermal method in the absence of any surfactant. With the addition of methenamine (HMT), SnO2 hollow microspheres with diameter of 2–3 μm and shell thickness of 60–140 nm were obtained. The gas sensitivity experiments showed that the as-synthesized SnO2 materials show good sensitivity to alcohol vapors and thus are expected to be useful in industrial applications such as gas sensors.
Co-reporter:Duoli Chai, XinSong Yuan, BaoJun Yang, Yitai Qian
Solid State Communications 2008 Volume 148(9–10) pp:444-447
Publication Date(Web):December 2008
DOI:10.1016/j.ssc.2008.09.018
Bismuth sulfide nanorods were synthesized on a large scale via a simple self-sacrificing template route, by the direct reaction between the pre-prepared precursor metallic bismuth NT arrays and thiourea (Tu) in air at 100 ∘C for 16 h. XRD, TEM, SEM and HRTEM characterizations show that the prepared Bi2S3 samples are all phase pure and the Bi2S3 nanorods have uniform diameters of approximately 30–50 nm and lengths up to several micrometers.
Co-reporter:S. Xiong;B. Xi;C. Wang;D. Xu;X. Feng;Z. Zhu;Y. Qian
Advanced Functional Materials 2007 Volume 17(Issue 15) pp:
Publication Date(Web):17 AUG 2007
DOI:10.1002/adfm.200600891
Semiconductor ZnS with novel and complex 3D architectures such as nanorods (or nanowires) networks, urchinlike nanosturctures, nearly monodisperse nanospheres self-assembled from nanorods and 1D nanostructures (rods and wires) had been synthesized in a binary solution by controlling the reaction conditions, such as the volume ratio of the mixed solvents and the reaction temperature. The morphology of ZnS changed from 3D architectural structures to 1D rodlike (or wirelike) shape when the temperature was increased from 160 to 200–240 °C. The possible growth mechanisms for the formation of nanospheres self-assembled from nanorods are tentatively discussed according to the experimental results. The photocatalytic activity of various ZnS nanostructures has been tested by degradation of acid fuchsine under infrared light compared to that of commercial ZnS powders under infrared-light irradiation and commercial TiO2 powders under UV-light irradiation, indicating that the as-obtained ZnS nanostructures exhibit excellent photocatalytic activity for degradation of acid fuchsine.
Co-reporter:Changlong Jiang, Wangqun Zhang, Guifu Zou, Weicao Yu, Yitai Qian
Materials Chemistry and Physics 2007 Volume 103(Issue 1) pp:24-27
Publication Date(Web):15 May 2007
DOI:10.1016/j.matchemphys.2006.11.001
ZnS hollow nanospheres have been hydrothermally synthesized at 200 °C for 4 h. In same condition ZnS microspheres were obtained when using acrylamide as the surfactant. XRD pattern indicates as-prepared sample is cubic ZnS with cell constant a = 5.391 Å and the average size of ZnS particles was 6.5 nm estimating from the Debye–Scherrer formula. TEM observed the hollow nanospheres have the diameters ranging from 200 to 300 nm with a shell thickness of about 40 nm. UV–vis and PL spectra recorded the optical properties of the sample, a blue-shift (∼19 nm) was observed. It appears that the hollow spheres might be formed by soft-template of gas bubbles of SO2 produced during the reaction.
Co-reporter:Xueying Wu, Jin Du, Haibo Li, Maofeng Zhang, Baojuan Xi, Hai Fan, Yongchun Zhu, Yitai Qian
Journal of Solid State Chemistry 2007 Volume 180(Issue 11) pp:3288-3295
Publication Date(Web):November 2007
DOI:10.1016/j.jssc.2007.07.010
Single-crystalline BaMoO4 microcrystals with uniform shuttle-like morphology have been successfully prepared via a facile aqueous solution mineralization process at room temperature. It was found that the pH value and the reaction temperature had important influences on the formation of the BaMoO4 microcrystals. The shuttle-like microcrystals can be obtained in alkaline aqueous solution (pH=9–14), and when the pH value was adjusted to 6–7, cocoon-like microcrystals appeared. A possible two-stage growth process has been proposed, and the Ostwald ripening was responsible for the formation of the shuttle-like BaMoO4 microcrystals. The products were characterized by XRD, XPS, FESEM, HRTEM and Raman spectroscopy. Room-temperature photoluminescence indicated that the as-prepared BaMoO4 microcrystals had a strong blue emission peak centered at 438 nm.A facile aqueous mineralization process has been used to synthesize uniform shuttle-like BaMoO4 microcrystals at room temperature. High quality, large scale, and uniform microcrystals with a mean length size of 50 μm can be easily obtained. These microcrystals exhibit single-crystal nature and perfect symmetry.
Co-reporter:Yi Liu, Meng Zhang, Yongqian Gao, Rui Zhang, Yitai Qian
Materials Chemistry and Physics 2007 Volume 101(2–3) pp:362-366
Publication Date(Web):15 February 2007
DOI:10.1016/j.matchemphys.2006.06.012
Co-reporter:Cun Li, Xiaogang Yang, Baojun Yang, Yan Yan, Yitai Qian
Materials Chemistry and Physics 2007 Volume 103(2–3) pp:427-432
Publication Date(Web):15 June 2007
DOI:10.1016/j.matchemphys.2007.02.057
Triazine-based nitrogen-rich graphitic carbon nitrides have been synthesized via two routes based on polycondensation reaction between melamine and cyanuric chloride in presence of nickel powder. The first route is a solvothermal method using benzene as solvent. The second one is a solvent-free solid reaction route. X-ray diffraction (XRD) patterns indicated that the synthesized products are graphite-like carbon nitride. Transmission electron microscopy (TEM) images reveal that the products mainly consist of 10–40 nm hollow spheres. The high atomic N/C ratio (1.60) determined by bulk element analysis shows the products are nitrogen-rich carbon nitrides. The chemical bonding structure and optical properties of the carbon nitride materials have been investigated by Fourier transform infrared spectroscopy (FTIR), Ultraviolet visible spectroscopy (UV–vis), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). The experimental results show that the products reserve the s-triazine structure. Both the products display the broad violet peak emission at about 408 nm.
Co-reporter:Yuanguang Zhang, Yi Liu, Shengquan Fu, Fan Guo, Yitai Qian
Materials Chemistry and Physics 2007 Volume 104(Issue 1) pp:166-171
Publication Date(Web):15 July 2007
DOI:10.1016/j.matchemphys.2007.03.003
Co3O4 crystallites with various morphologies such as urchin-like morphology, spherical morphology, quasi-cubic morphology have been selectively prepared at different synthetic conditions. The as-prepared products were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and transmission electron microscopy (TEM). Some influencing factors including reaction temperature, reaction time, different surfactant, and cobalt source on the morphologies of the final products have been discussed. In addition, the possible formation mechanism of quasi-cubic morphology of Co3O4 crystallites is also proposed based on its crystal structure and experimental results.
Co-reporter:Junhao Zhang, Jin Du, Dekun Ma, Guangcheng Xi, Xiaobo Hu, Yitai Qian
Solid State Communications 2007 Volume 144(3–4) pp:168-173
Publication Date(Web):October 2007
DOI:10.1016/j.ssc.2007.06.026
Co-reporter:Shenglin Xiong Dr.;Baojuan Xi;Chengming Wang;Guangcheng Xi Dr.;Xiaoyan Liu Dr.
Chemistry - A European Journal 2007 Volume 13(Issue 28) pp:
Publication Date(Web):6 JUL 2007
DOI:10.1002/chem.200700334
A general and facile synthetic route has been developed to prepare 1D semiconductor nanomaterials in a binary solution of distilled water and ethanol amine. The influence of the volume ratio of mixed solvents and reaction temperature on the yield and final morphology of products was investigated. Significantly, this is the first time that wurtzite ZnSe ultrathin nanobelts have been synthesized in solution. It has been confirmed that the photocatalytic activity of ZnSe nanobelts in the photodegradation of the fuchsine acid is higher than that of TiO2 nanoparticles. The present work shows that the solvothermal route is facile, cheap, and versatile. Thus, it is very easy to realize scaled-up production, and brings new light on the synthesis and self-assembly of functional materials.
Co-reporter:Shenglin Xiong Dr.;Baojuan Xi;Chengming Wang;Guifu Zou Dr.;Lifeng Fei;Weizhi Wang Dr.
Chemistry - A European Journal 2007 Volume 13(Issue 11) pp:
Publication Date(Web):10 JAN 2007
DOI:10.1002/chem.200600786
A facile L-cysteine-assisted route was designed for the selectively controlled synthesis of 1D and novel, interesting 3D CdS spherical nanostructures constructed from CdS nanorods (or nanopolypods) in a binary solution. By controlling reaction conditions such as the molar ratio between Cd(OAc)2 and L-cysteine and the volume ratio of the mixed solvents, the synthesis of various 3D architectural structures and 1D wirelike structures in large quantities can be controlled. This is the first reported case of the direct growth of novel 3D self-assemblies of CdS nanorods (or nanopolypods). The morphology, structure, and phase composition of the as-prepared CdS products were examined by using various techniques (X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), high-resolution TEM, and Raman spectroscopy). On the basis of the results from TEM studies and our analysis, we speculate that in the present synthesis the L-cysteine dominates nucleation growth and the ethylenediamine (en)-dominated, oriented-assembly process. Interestingly, the products obtained show a gradient evolution in color from light-yellow to dark-yellow, which implies that their intrinsic optical properties change, possibly due to variations in their special morphologies and structures. This facile solution-phase L-cysteine-assisted method could be extended for the controlled preparation of other metal chalcogenides nanostructures with complex morphologies.
Co-reporter:Guifu Zou, Dawei Zhang, Chao Dong, Hui Li, Kan Xiong, Linfeng Fei, Yitai Qian
Carbon 2006 Volume 44(Issue 5) pp:828-832
Publication Date(Web):April 2006
DOI:10.1016/j.carbon.2005.10.035
Carbon nanofibers (CNFs) have been synthesized by co-catalyst deoxidization process by a reaction between C2H5OC2H5, Zn and Fe powder at 650 °C for 10 h. These nanofibers exhibit diameters of ∼80 nm and lengths ranging from several micrometers to tens of micrometers. X-ray diffraction, Raman spectroscopy, and high-resolution transmission electron microscopy indicate that as-prepared CNFs possess low graphitic crystallinity. The resultant CNFs as electrode shows capacity of ∼220 mAh/g and high reversibility with little hysteresis in the insertion/deintercalation reactions of lithium-ion. In addition, the possible growth of CNFs is discussed.
Co-reporter:Shenglin Xiong;Linfeng Fei;Zhenghua Wang;Hong Yang Zhou;Weizhi Wang
European Journal of Inorganic Chemistry 2006 Volume 2006(Issue 1) pp:
Publication Date(Web):17 NOV 2005
DOI:10.1002/ejic.200500654
We report on the preparation of ultralong semiconductor tellurium/cross-linked PVA coaxial nanocables with a core 20–30 nm in diameter and a surrounding sheath about 5–20 nm in thickness by a simple hydrothermal process. The length of these nanocables can be up to 500–800 μm. In the present synthesis PVA was used as the reducing agent to react with Na2TeO3, and it also serves as the capping reagent and the source of the sheaths. The synergistic effects of the interaction of cross-linked PVA with the tellurium nanowires could play an important role in the formation of the morphology of the resulting products.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Co-reporter:By-Qin Xie;Shuyuan Zhang;Shenquan Fu;Weichao Yu
European Journal of Inorganic Chemistry 2006 Volume 2006(Issue 12) pp:
Publication Date(Web):11 APR 2006
DOI:10.1002/ejic.200600061
Hexagonal close-packed (hcp) cobalt nanowires with diameters of 150–300 nm and lengths of up to several hundreds of micrometers have been synthesized by a hydrothermal reduction method. These cobalt nanowires were generated by the reduction of cobalt(II) citrate complexes by hypophosphite (H2PO2–) in basic solution at 160 °C. High-resolution TEM and SAED reveal that the as-prepared Co nanowires have a single-crystalline structure with a [001] growth direction. The room-temperature hysteresis loop of these nanowires shows a ferromagnetic behavior with enhanced coercivity. A formation mechanism for these Co nanowires is proposed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Co-reporter:Changlong Jiang, Guifu Zou, Wangqun Zhang, Weicao Yu, Yitai Qian
Materials Letters 2006 Volume 60(Issue 19) pp:2319-2321
Publication Date(Web):August 2006
DOI:10.1016/j.matlet.2005.12.133
Flower-like microstructures of ferromagnetic Ni nanotips have been synthesized in aqueous solution at 140 °C for 12 h. XRD pattern indicated the sample is cubic Ni with lattice constant a = 3.514 Å. FE-SEM shown the formation process of Ni sample. Room temperature magnetic characterization of as-prepared Ni sample demonstrates much enhanced ferromagnetic property. The hydrazine hydrate was used as reduced agent and ligand in present synthesis, the possible formation mechanism was also discussed.
Co-reporter:Yongchun Zhu, Qing Yang, Huagui Zheng, Lisheng Gao, Zhiping Yang, Yitai Qian
Materials Chemistry and Physics 2006 Volume 96(2–3) pp:506-510
Publication Date(Web):10 April 2006
DOI:10.1016/j.matchemphys.2005.07.046
Zn-doped Ni nanotubes with wall thickness in the range of 10–20 and 100–200 nm in inner diameter have been synthesized in ethanol via a room-temperature solution synthetic route. Powder X-ray diffraction (XRD) pattern shows that the as-synthesized particles have a chemically disordered fcc structure. The coercivity of the products was investigated to be 515.6 Oe at room temperature. The catalytic property of Zn-doped Ni nanotubes was also conducted.
Co-reporter:Yi Liu, Meng Zhang, Junhao Zhang, Yitai Qian
Journal of Solid State Chemistry 2006 Volume 179(Issue 6) pp:1757-1761
Publication Date(Web):June 2006
DOI:10.1016/j.jssc.2006.02.028
α-MnO2 nanowires or nanorods have been selectively synthesized via the hydrothermal method in nitric acid condition. The α-MnO2 nanowires hold with average diameter of 50 nm and lengths ranging between 10 and 40 μm, using MnSO4·H2O as manganese source; meanwhile, α-MnO2 bifurcate nanorods with average diameter of 100 nm were obtained by adopting MnCO3 as starting material. The morphology of α-MnO2 bifurcate nanorods is the first one to be reported in this paper. X-ray powder diffraction (XRD), field scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM) were used to characterize the products. Experimental results indicate that the concentrated nitric acid plays a crucial role in the phase purity and morphologies of the products. The possible formation mechanism of α-MnO2 nanowires and nanorods has been discussed.α-MnO2 nanowires or nanorods have been selectively synthesized via the hydrothermal method in nitric acid condition. The α-MnO2 nanowires hold with average diameter of 50 nm and lengths ranging between 10 and 40 μm, using MnSO4·H2O as manganese source; meanwhile, α-MnO2 bifurcate nanorods with average diameter of 100 nm were obtained by adopting MnCO3 as starting material.
Co-reporter:Aiwu Zhao, Tao Luo, Luyang Chen, Yong Liu, Xiaoguang Li, Qun Tang, Peijun Cai, Yitai Qian
Materials Chemistry and Physics 2006 Volume 99(Issue 1) pp:50-53
Publication Date(Web):10 September 2006
DOI:10.1016/j.matchemphys.2005.10.013
High-density aligned ZnO nanorods films were grown on zinc-covered Si wafer by using hydrothermal method in the alkali solution containing hydrogen peroxide (H2O2). The growth process involves the oxidation of zinc into oxidized zinc species cluster in the alkali solution containing hydrogen peroxide (H2O2) and the ZnO nanorods growth process in which oxidized zinc species provide seeds for nucleation site of nanorods ZnO crystal growth during hydrothermal process. The hydrogen peroxide plays a key role in formation of oxidized zinc species cluster. Room temperature PL spectrum and Raman spectrum of the sample are also studied and indicate that there is a very low concentration of oxygen vacancies in the highly oriented ordered ZnO nanorods.
Co-reporter:S. Xiong;J. Shen;Q. Xie;Y. Gao;Q. Tang;Y. T. Qian
Advanced Functional Materials 2005 Volume 15(Issue 11) pp:
Publication Date(Web):6 SEP 2005
DOI:10.1002/adfm.200500069
A large number of one-dimensional bundles of ZnSe nanowires with diameters ranging from 15–20 nm and lengths of up to tens of micrometers have been prepared via the thermal treatment of a ribbon-like precursor (ZnSe·3ethylenediamine), which has been synthesized by a mixed solvothermal route, in an argon atmosphere. The as-obtained precursor has been characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), IR spectroscopy, thermogravimetric analysis, and elemental analysis. XRD and high-resolution TEM characterization reveal that the as-synthesized ZnSe nanowires have the single-crystal hexagonal wurtzite structure with the [001] growth direction. The surface chemical composition of ZnSe nanowires has been studied by X-ray photoelectron spectroscopy. The cooperative action of the mixed solvents may be responsible for the formation of the morphology of the resulting products. Room-temperature photoluminescence measurements indicate the as-grown ZnSe nanostructures have a strong emission peak centered at 587 nm and two weak emission peaks centered at 435 and 462 nm. The strong emission from the ZnSe nanostructures reveals their potential as building blocks for optoelectronic devices.
Co-reporter:Liqiang Xu, Jianwei Liu, Jin Du, Yiya Peng, Yitai Qian
Carbon 2005 Volume 43(Issue 7) pp:1560-1562
Publication Date(Web):June 2005
DOI:10.1016/j.carbon.2004.12.030
Co-reporter:Wanqun Zhang;Liqiang Xu;Kaibin Tang;Fanqing Li
European Journal of Inorganic Chemistry 2005 Volume 2005(Issue 4) pp:
Publication Date(Web):7 JAN 2005
DOI:10.1002/ejic.200400625
Highly uniform urchin-like nanostructures (in the structures, nanoneedles or nanobelts grow radially from the core particles) of NiS (millerite) were successfully prepared by a solvothermal synthetic route using Ni(Ac)2·6H2O and dithizone as reagents and ethylenediamine as solvent in the temperature range of 220−240 °C. The prepared nickel sulfides with urchin-like 3D architectures were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HRTEM). The reaction temperature, sulfur sources, and solvent are of great importance on the final urchin-like structures. On the basis of the experimental results, a possible growth mechanism of the urchin-like NiS crystals is proposed, which is supported by the technical characterizations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Co-reporter:Junxi Wan;Zhenghua Wang;Xiangying Chen;Li Mu
European Journal of Inorganic Chemistry 2005 Volume 2005(Issue 20) pp:
Publication Date(Web):12 SEP 2005
DOI:10.1002/ejic.200500502
Sr2MgSi2O7:Eu3+ nanotubes with red phosphor luminescent properties were successfully synthesized via a low-temperature hydrothermal route in order to understand the underlying relationship between shape and luminescent properties. The one-dimensional shape results in an obvious improvement of color purity. From emission spectra, the relative intensity of 5D07F2 to 5D07F1 transitions in tubular phosphors is higher than that of bulk material. The better color purity results from the more distorted lattices and relatively lower crystal symmetry around Eu3+ ions, which ascribes to the large surface area due to synthesize it in the form of nanotubes. Furthermore, the as-synthesized tubular red phosphor has shorter fluorescent lifetime and blue-shiftphenomenon in excitation spectra than that of the bulk counterpart. Based on these results, shape-induced luminescent properties improvement is proposed as an efficient way to obtain red phosphors with high color purity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Co-reporter:Baojun Yang, Yucheng Wu, Hanmei Hu, Cun Li, Xiaogang Yang, Yitai Qian
Materials Chemistry and Physics 2005 Volume 92(Issue 1) pp:286-289
Publication Date(Web):15 July 2005
DOI:10.1016/j.matchemphys.2005.01.034
Antimony dendritic nanocrystals have been prepared in a large scale by the reduction of Sb3+ with metallic zinc powder at room temperature in aqueous or alcoholic solution. It is found that homogeneous Sb3+ solution and rapid reduction reaction play important role in the formation of Sb dendrites. The possible formation mechanism of Sb dendrites is also investigated.
Co-reporter:Changlong Jiang, Wangqun Zhang, Guifu Zou, Liqiang Xu, Weicao Yu, Yitai Qian
Materials Letters 2005 Volume 59(8–9) pp:1008-1011
Publication Date(Web):April 2005
DOI:10.1016/j.matlet.2004.11.046
Novel copper sulfide nanocones and nanobelts have been hydrothermally fabricated at 140 °C for 24 h with acrylamide and sodium dodecyl benzene sulfonate (SDBS) as surfactants, respectively. X-ray diffraction (XRD) pattern indicates that the as-prepared samples are the pure hexagonal phase CuS. XPS spectra show that the ratio of Cu/S is about 1:1.084. The morphology was characterized by scanning electron microscopy (SEM) and field emission scanning electron microscopy (FE-SEM) techniques. Transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images reveal that nanocones and nanobelts grow along the [110] axis. The surfactant is found to be critical to the morphologies of the products. The possible formation mechanism is also discussed.
Co-reporter:Meng Zhang, Zhenghua Wang, Maosong Mo, Xiangying Chen, Rui Zhang, Weichao Yu, Yitai Qian
Materials Chemistry and Physics 2005 Volume 89(2–3) pp:373-378
Publication Date(Web):15 February 2005
DOI:10.1016/j.matchemphys.2004.09.016
Potassium nickel fluoride (KNiF3) hollow spheres with diameters of 200–400 nm have been solvothermally synthesized at 110 °C using KF and NiCl2 as reactants in ethanol, without additional template materials or surfactants. The results of XRD and XPS indicate that the products are perovskite-type KNiF3. TEM microphotos show that the hollow spheres are composed of KNiF3 nanoparticles with an average size of 10 nm, and the wall thickness is 20–40 nm. UV–vis and PL spectra have recorded the optical properties of KNiF3 hollow spheres. A possible mechanism for the formation of KNiF3 hollow spheres is also discussed.
Co-reporter:Zhenghua Wang, Xiangying Chen, Meng Zhang, Yitai Qian
Solid State Sciences 2005 Volume 7(Issue 1) pp:13-15
Publication Date(Web):January 2005
DOI:10.1016/j.solidstatesciences.2004.10.032
Co3O4 nanorods were successfully synthesized from a single precursor via a thermal decomposition and oxidization route. The precursor used was Co(CO3)0.35Cl0.20(OH)1.10, which was prepared by a hydrothermal reaction using CoCl2⋅6H2O with CO(NH2)2 at 95–120 °C. Both the precursor and the as-prepared Co3O4 were characterized with XRD, TEM, SEM, TGA and XPS. The precursor, as well as Co3O4, was found to be composed of nanorods that were radially bunched. The Co3O4 nanorods obtained through a thermal treatment at 300 °C for 5 h were found to have a porous structure.
Co-reporter:Peijun Cai, Luyang Chen, Liang Shi, Zeheng Yang, Aiwu Zhao, Yunle Gu, Tao Huang, Yitai Qian
Solid State Communications 2005 Volume 133(Issue 10) pp:621-623
Publication Date(Web):March 2005
DOI:10.1016/j.ssc.2005.01.011
We describe one convenient synthesis route to boron nitride (BN) nanotube by the reaction of boron powder, iron oxide, and ammonium chloride at 600 °C for 12 h. Characterized by XRD, FTIR, XPS, TEM and SAED, the composition and morphology of the products are confirmed. The possible reaction mechanism is also discussed.
Co-reporter:Qin Xie, Zhou Dai, Jianbo Liang, Liqiang Xu, Weichao Yu, Yitai Qian
Solid State Communications 2005 Volume 136(Issue 5) pp:304-307
Publication Date(Web):November 2005
DOI:10.1016/j.ssc.2005.07.023
Uniform ZnO urchin-like architectures were synthesized by hydrothermal decomposing Zn(OH)42− precursor with the assistance of dodecylamine (DDA) at 180 °C for 12 h. FESEM images display that the ZnO 3D urchin-like architectures are constructed of well-aligned ZnO nanorods with diameters of 50–80 nm and lengths up to 2 μm. Room temperature photoluminescence spectra of ZnO 3D architectures show an intensive ultraviolet emission at ∼385 nm and weak green emission, which indicated their high structural and optical quality.
Co-reporter:Qun Tang, Ting Li, Xihong Chen, Dapeng Yu, Yitai Qian
Solid State Communications 2005 Volume 134(Issue 3) pp:229-231
Publication Date(Web):April 2005
DOI:10.1016/j.ssc.2004.09.063
Well-oriented Cu2O films comprising of octahedral-shaped crystals were grown directly on copper foil via an hydrothermal treatment. The well-oriented films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Field emission from the film showed good emission properties, and, the electron emission turn-on field (Eto) and threshold field (Ethr) are about 9.6 and 13.4 V/μm respectively, which is similar to the values reported for CuO nanofiber, although the latter has a much larger size. The corresponding Fowler–Nordheim (F–N) plots showed a linear behavior. The sharp corners of the tips are considered as main electron emitters and account for its good performance.
Co-reporter:Zhenghua Wang Dr.;Jianwei Liu Dr.;Xiangying Chen Dr.;Junxi Wan Dr.
Chemistry - A European Journal 2005 Volume 11(Issue 1) pp:
Publication Date(Web):3 NOV 2004
DOI:10.1002/chem.200400705
This paper describes the preparation of uniform silver nanowires by reducing freshly prepared silver chloride with glucose at 180 °C for 18 hours in the absence of any surfactants or polymers. Scanning electron microscopy studies indicated that the silver nanowires are about 100 nm in diameter and up to 500 μm in length. High-resolution transmission electron microscopy analyses showed that the silver nanowires grow perpendicularly to the Ag(200) plane. The silver nanowires are believed to grow through a solid–solution–solid process. Some influential factors on the growth of silver nanowires are also discussed.
Co-reporter:Zhaoping Liu, Jianbo Liang, Dan Xu, Jun Lu and Yitai Qian
Chemical Communications 2004 (Issue 23) pp:2724-2725
Publication Date(Web):06 Oct 2004
DOI:10.1039/B409825K
We report a facile chemical route for the synthesis of monodisperse nanocrystals of various metal sulfides (PbS, Cu2S, and Ag2S) and their assemblies into nanocrystal superlattices (NCSs); the sulfides NCSs were precipitated by adding ethanol to nanocrystal colloids, which were obtained directly by a reaction between metal thiolate and thioacetamide in a pure dodecanethiol solvent.
Co-reporter:Xiaogang Yang, Cun Li, Wei Wang, Baojun Yang, Shuyuan Zhang and Yitai Qian
Chemical Communications 2004 (Issue 3) pp:342-343
Publication Date(Web):13 Jan 2004
DOI:10.1039/B313733C
Amorphous carbon nanospheres with diameters of 140–200 nm have been synthesized by treating poly(tetrafluoroethylene) in supercritical water at 550 °C using Ca(OH)2 as defluorination reagent.
Co-reporter:Baojun Yang;Maosong Mo;Hanmei Hu;Cun Li;Xiaogang Yang;Qiaowei Li
European Journal of Inorganic Chemistry 2004 Volume 2004(Issue 9) pp:
Publication Date(Web):20 APR 2004
DOI:10.1002/ejic.200300966
Arrayed β-Bi2O3 nanotubes (NTs) were synthesized for the first time through a rational “self-sacrificing template” route, simply by oxidizing the precursor metallic bismuth NT arrays in air at 200−220 °C for 14−18 h. XRD, TEM, and HRTEM characterizations show that the prepared β-Bi2O3 samples are all phase pure and the β-Bi2O3 NTs have uniform diameters of approximately 3−6 nm and lengths up to several micrometers. The optical absorption and photoluminescence (PL) characteristics of the prepared samples were investigated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Co-reporter:Guifu Zou;Zhaopin Liu;Debao Wang;Changlong Jiang
European Journal of Inorganic Chemistry 2004 Volume 2004(Issue 22) pp:
Publication Date(Web):1 OCT 2004
DOI:10.1002/ejic.200400401
For the first time, hollow PbTe nanospheres with diameters of 80−140 nm have been prepared in an ether/glycerol microemulsion system and PbTe single-crystalline nanotubes with diameters of 60−80 nm have been synthesised in a homogeneous ethanol/glycerol system. They can be facilely controlled via a solvothermal process without any additional catalysts and templates. Two different template mechanisms are discussed herein. The Raman and far infrared spectra of the samples have been investigated at room temperature. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Co-reporter:Dabin Yu, Debao Wang, Yitai Qian
Journal of Solid State Chemistry 2004 Volume 177(4–5) pp:1230-1234
Publication Date(Web):April–May 2004
DOI:10.1016/j.jssc.2003.10.030
Single-crystalline metastable In2O3 nanocrystals with size in the range of 5–30 nm were, for the first time, synthesized by a precursor-dehydration route at 490°C under ambient pressure. The precursor was prepared by a hydrolysis solvothermal reaction using InCl3·4H2O as starting materials and ethylenediamine as solvent in the range of 180–230°C. It was found that the precursor had significant effect on the phase composition and phase structure of In2O3. Optical properties of the metastable In2O3 nanocrystals were investigated.
Co-reporter:Junxi Wan, Xiangying Chen, Zhenghua Wang, Weichao Yu, Yitai Qian
Materials Chemistry and Physics 2004 Volume 88(Issue 1) pp:217-220
Publication Date(Web):15 November 2004
DOI:10.1016/j.matchemphys.2004.07.013
PbS nanorod bundles have been synthesized via a surfactant-assisted biphasic interface reaction route at 160 oC for 20 h. The as-prepared nanorods have diameter of 30 nm and length of 0.8 μm. Based on the observation of transmission electron microscopy (TEM) images, it is found that the amount of sodium dodecyl sulfonate (SDS) plays a crucial role on the morphology of the products. The formation of one-dimensional (1D) PbS nanostructures could be ascribed to the confined growth between surfactant chains. A possible mechanism is also discussed.
Co-reporter:Luyang Chen, Yunle Gu, Yitai Qian, Liang Shi, Zeheng Yang, Jianhua Ma
Materials Research Bulletin 2004 Volume 39(4–5) pp:609-613
Publication Date(Web):2 April 2004
DOI:10.1016/j.materresbull.2003.12.005
Nanocrystalline titanium diboride (TiB2) has been prepared by the reaction of TiCl4 with NaBH4 in the temperature range of 500–700 °C in an autoclave. X-ray powder diffraction (XRD) patterns can be indexed as hexagonal TiB2 with the lattice constants of a=3.032 and c=3.229 Å. Transmission electron microscopy (TEM) image shows particle morphology, with average size of 15 nm for the powder obtained at 600 °C. Selected area electron diffraction (SAED) pattern confirms the prepared hexagonal TiB2. The oxidation behavior of TiB2 is studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA).
Co-reporter:Liang Shi, Yunle Gu, Luyang Chen, Yitai Qian, Zeheng Yang, Jianhua Ma
Journal of Solid State Chemistry 2004 Volume 177(Issue 3) pp:721-724
Publication Date(Web):March 2004
DOI:10.1016/j.jssc.2003.08.026
Nanocrystalline boron nitride (BN) with needle-like and hollow spherical morphology has been synthesized by nitriding of MgB2 with NH4Cl and NH4Cl–NaN3, respectively. The amount of NaN3 has an obvious effect on the size of the hollow spheres. The samples were characterized by X-ray powder diffraction, Fourier transformation infrared spectroscopy, X-ray photoelectron spectra, and transmission electron microscopy. The possible mechanism of morphology control is also discussed.
Co-reporter:Lingfen Kong, Zhaoping Liu, Mingwang Shao, Qin Xie, Weichao Yu, Yitai Qian
Journal of Solid State Chemistry 2004 Volume 177(Issue 3) pp:690-695
Publication Date(Web):March 2004
DOI:10.1016/j.jssc.2003.08.035
VOx·nH2O (2.0⩽x⩽2.5) nanoribbons have been synthesized by direct hydrothermal processing of the aqueous solution of NH4VO3 and polyethylene glycol 400 (PEG-400) at pH 3.5–5.5. Techniques of XRD, SEM, TEM, HRTEM, ED, and XPS have been used to characterize the structure, morphology, and composition of the nanoribbons. The VOx·nH2O nanoribbons are up to ∼200 μm in length, 100–150 nm in width, 20–30 nm in thickness, and grow along the [010] direction. The ratios of V4+ to V5+ in the products can be readily controlled by carefully adjusting the periods of reaction time. PEG carries the roles of both transport and reducing agent. A coordination self-assembly mechanism was proposed to elucidate the formation of the VOx·nH2O nanoribbons.
Co-reporter:Zhaoping Liu Dr.;Jianbo Liang;Shu Li;Sheng Peng
Chemistry - A European Journal 2004 Volume 10(Issue 3) pp:
Publication Date(Web):2 FEB 2004
DOI:10.1002/chem.200305481
This article describes a facile solvothermal method by using mixed solvents for the large-scale synthesis of Bi2S3 nanoribbons with lengths of up to several millimeters. These nanoribbons were formed by a solvothermal reaction between BiIII–glycerol complexes and various sulfur sources in a mixed solution of aqueous NaOH and glycerol. HRTEM (high-resolution transmission electron microscopy) and SAED (selective-area electron diffraction) studies show that the as-synthesized nanoribbons had predominately grown along the [001] direction. The Bi2S3 nanoribbons prepared by the use of different sulfur sources have a common formation process: the initial formation of NaBiS2 polycrystals, which serve as the precursors to Bi2S3, the decomposition of NaBiS2, and the formation of Bi2S3 seeds in the solution through a homogeneous nucleation process; the growth of Bi2S3 nanoribbons occurs at the expense of NaBiS2 materials. The growth mechanism of millimeter-scale nanoribbons involves a special solid–solution–solid transformation as well as an Ostwald ripening process. Some crucial factors affect nanoribbon growth, such as, solvothermal temperature, volume ratio of glycerol to water, and the concentration of NaOH; these have also been discussed.
Co-reporter:K.-B. Tang;Y.-T. Qian;J.-H. Zeng;X.-G. Yang
Advanced Materials 2003 Volume 15(Issue 5) pp:
Publication Date(Web):7 MAR 2003
DOI:10.1002/adma.200390104
Solvothermal synthesis is an important technology for the preparation of nanowires at low temperature. Nanowires can grow as long as 100 μm with the aid of polymer matrix, and under the pressure generated by solvothermal reactions, the as-prepared nanowires are well crystallized. For water-sensitive reactions, solvothermal reactions can fully avoid the presence of water. We discuss here the synthesis of a variety of nanowire structures, including CdS–CdSe core–sheath nanowires and very long CdS nanowires, and the solvothermal closure of PbS nanowires. Now that an appropriate procedure has been established, the solvothermal reactions are efficient and time-saving.
Co-reporter:Z. Liu;S. Li;Y. Yang;S. Peng;Z. Hu;Y. Qian
Advanced Materials 2003 Volume 15(Issue 22) pp:
Publication Date(Web):20 NOV 2003
DOI:10.1002/adma.200305663
Co-reporter:Z. Liu;S. Peng;Q. Xie;Z. Hu;Y. Yang;S. Zhang;Y. Qian
Advanced Materials 2003 Volume 15(Issue 11) pp:
Publication Date(Web):2 JUN 2003
DOI:10.1002/adma.200304693
Co-reporter:D. Yu;S.-H. Yu;S. Zhang;J. Zuo;D. Wang;Y.T. Qian
Advanced Functional Materials 2003 Volume 13(Issue 6) pp:
Publication Date(Web):5 JUN 2003
DOI:10.1002/adfm.200304303
Single-crystal, metastable, hexagonal In2O3 (H-In2O3) nanofibers with an average diameter of 80 nm and length of up to several micrometers were synthesized on a large scale, for the first time under ambient pressure, by annealing InOOH nanofibers at 490 °C. The InOOH nanofibers were prepared by a controlled hydrolysis solvothermal reaction, using InCl3·4H2O as the starting material and ether as the solvent, in the temperature range of 190–240 °C. The solvent has significant effects on the formation of the metastable phase and the morphology of the In2O3 nanocrystals during the synthesis of the precursor InOOH. Room-temperature optical absorption spectra of the hexagonal In2O3 nanofibers showed strong absorption peak located at 325 nm (3.83 eV) with a slight blue-shift compared with that of bulk In2O3 (3.75 eV). The H-In2O3 nanofibers photoluminesce at room temperature with emission peaks at 378 nm, 398 nm, and 420 nm. The successful production of metastable hexagonal In2O3 nanofibers in large scale under mild conditions could be of interest both for applications and fundamental studies.
Co-reporter:Zhaoping Liu, Zhaokang Hu, Qin Xie, Baojun Yang, Ji Wu and Yitai Qian
Journal of Materials Chemistry A 2003 vol. 13(Issue 1) pp:159-162
Publication Date(Web):14 Nov 2002
DOI:10.1039/B208420A
Uniform tellurium single crystal nanorods with diameters of 14 nm and lengths of 300 nm were prepared through reduction of [TeS4]2− by SO32− with use of a suitable surfactant, sodium dodecyl benzenesulfonate (NaDDBS). Te nanorods with various diameters can be prepared by carefully adjusting the concentration of NaDDBS or the initial concentration of TeS42−. The nucleation and growth processes of Te nanorods were interpreted by solid–solution–solid transformation and surfactant-assisted growth mechanism.
Co-reporter:Cun Li;Xiaogang Yang;Baojun Yang;Yan Yan
European Journal of Inorganic Chemistry 2003 Volume 2003(Issue 19) pp:
Publication Date(Web):18 SEP 2003
DOI:10.1002/ejic.200300183
Hollow sphere-like carbides MC (M = Ti, V) with diameters of between 70 and 170 nm were synthesized via a template-interface co-reduction (TICR) route, in which MCl4 and hexachlorobuta-1,3-diene (C4Cl6) were reacted with metallic sodium at 500 °C for 24 h. X-ray powder diffraction (XRD) patterns indicated the samples were single-phase NaCl-type carbides. Transmission electron microscopy (TEM) photographs showed the hollow spheres consisted of nanocrystalline carbides. The possible formation mechanism of hollow sphere-like carbides is discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Co-reporter:Baojun Yang;Cun Li;Hanmei Hu;Xiaogang Yang;Qiaowei Li
European Journal of Inorganic Chemistry 2003 Volume 2003(Issue 20) pp:
Publication Date(Web):13 OCT 2003
DOI:10.1002/ejic.200300347
A room-temperature aqueous-chemical route has been developed to synthesize a high proportion (above 80%) of bamboo-raft-like bismuth nanotube arrays using bismuth chloride and metallic zinc powder as reagents. The prepared Bi nanotubes have uniform diameters of approximately 3−5 nm and lengths from several hundred nanometers to several micrometers. HRTEM observations show that the axial direction of the prepared nanotubes is along the normal direction of the (012) lattice planes of the rhombohedral bismuth. The possible formation mechanism is discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Co-reporter:Zhaoping Liu, Shu Li, You Yang, Zhaokang Hu, Sheng Peng, Jianbo Liang and Yitai Qian
New Journal of Chemistry 2003 vol. 27(Issue 12) pp:1748-1752
Publication Date(Web):24 Sep 2003
DOI:10.1039/B306782C
Single crystalline one-dimensional (1D) nanostructures of trigonal tellurium (t-Te) with well-controlled shapes and sizes were synthesized by the hydrothermal reduction of Na2TeO3 in a mixed solution of ethanol and water at 100°C. The formation of various 1D nanostructures of t-Te was mainly determined by properly controlling the nucleation and growth rate of t-Te in different reaction media. In acidic solution (1 M of HCl), the reaction gave nanowires with diameters of ∼30–100 nm, while in alkaline solution (1 M of NaOH), it yielded tubular crystals with diameters of ∼1–2 μm. The diameters of tubular crystals could also be controlled by adjusting the NaOH concentration. When polymer surfactant poly(vinyl pyrrolidone)
(PVP) was presented in the alkaline solution, the reaction would produce uniform nanowires with diameters of ∼25 nm. Based on the TEM and SEM studies, the formation mechanisms for these 1D nanostructures were rationally interpreted. The crystallinity of the nanowires and the tubular crystals were determined by HRTEM, ED, and XRD.
Co-reporter:Hanmei Hu, Maosong Mo, Baojun Yang, Mingwang Shao, Shuyuan Zhang, Qiaowei Li and Yitai Qian
New Journal of Chemistry 2003 vol. 27(Issue 8) pp:1161-1163
Publication Date(Web):02 Jul 2003
DOI:10.1039/B303712F
Antimony nanotubes with inner diameters of 15–80 nm, wall thickness of 10–30 nm and lengths of up to several micrometers have been successfully prepared by a rational complexing-reduction route using zinc powder as reductant at low temperature (80–140°C).
Co-reporter:Yong Cui, Gang Chen, Jin Ren, Mingwang Shao, Yi Xie, Yitai Qian
Journal of Solid State Chemistry 2003 Volume 172(Issue 1) pp:17-21
Publication Date(Web):April 2003
DOI:10.1016/S0022-4596(02)00040-3
Crystalline β-Ag2Se with treelike, plumelike, pebblelike, rodlike, tubular, polyhedral, and spherical morphologies have been prepared by the solvothermal reaction of silver carbonate and selenium at low temperature (190°C) and characterized by elemental analysis, X-ray diffraction pattern, and scanning electron microscopy. The morphologies and sizes of the products are affected not only by the kind of solvents but also by the reactant concentrations and reaction time and can be conveniently obtained under controlled conditions. The influences of the solvents, the reactant concentrations and reaction time on the shapes and sizes of crystalline Ag2Se are discussed.
Co-reporter:Rong-Bo Zheng, Jing-Hui Zeng, Mao-Song Mo, Yi-Tai Qian
Materials Chemistry and Physics 2003 Volume 82(Issue 1) pp:116-119
Publication Date(Web):28 September 2003
DOI:10.1016/S0254-0584(03)00215-3
Lamella and parallelogram thin flake NaInS2, KInS2 nanocrystals were prepared by the reaction between Na2S·9H2O or K2S and InCl3·4H2O via solvothermal method at low temperature. The result of electron diffraction (ED) analysis confirmed that lamella of NaInS2 nanocrystal grows along the directions perpendicular to the 〈0 0 1〉 zone axis. The reaction temperature played a key role in the formation of NaInS2 nanocrystal. Meanwhile, the process of NaInS2 nanocrystal growth was discussed.
Co-reporter:Jianhua Ma, Yunle Gu, Liang Shi, Luyang Chen, Zeheng Yang, Yitai Qian
Chemical Physics Letters 2003 Volume 381(1–2) pp:194-198
Publication Date(Web):4 November 2003
DOI:10.1016/j.cplett.2003.09.128
Chromium boride (CrB) nanorods were synthesized via a reduction–boronation route at 650 °C in molten salt in an autoclave. The X-ray diffraction pattern of the product was indexed as the orthorhombic CrB. Transmission electron microscope images indicated that the sample consisted of single-crystalline nanorods with the diameter of 10–30 nm and a maximum length of 1.5 μm. The PL spectra showed the ultraviolet light emission at 340 nm. The thermogravimetric analysis showed that the product also had very good anti-oxidation properties below 630 °C. A possible growth mechanism was proposed.
Co-reporter:Xin-yuan Liu, Jing-hui Zeng, Shu-yuan Zhang, Rong-bo Zheng, Xian-ming Liu, Yi-tai Qian
Chemical Physics Letters 2003 Volume 374(3–4) pp:348-352
Publication Date(Web):11 June 2003
DOI:10.1016/S0009-2614(03)00730-9
Abstract
Novel bismuth nanotube arrays have been successfully synthesized by a solvothermal method through the reduction of bismuth oxide (Bi2O3) by ethylene glycol (EG). The productions were characterized by XRD, TEM and HRTEM. The diameter of the nanotubes is about 3–6 nm and length is up to 500 nm. The possible growth mechanism of Bi nanotubes was discussed.
Co-reporter:M. Mo;J. Zeng;X. Liu;W. Yu;S. Zhang;Y. Qian
Advanced Materials 2002 Volume 14(Issue 22) pp:
Publication Date(Web):22 NOV 2002
DOI:10.1002/1521-4095(20021118)14:22<1658::AID-ADMA1658>3.0.CO;2-2
Co-reporter:Dabin Yu, Debao Wang, Zhaoyu Meng, Jun Lu and Yitai Qian
Journal of Materials Chemistry A 2002 vol. 12(Issue 3) pp:403-405
Publication Date(Web):01 Feb 2002
DOI:10.1039/B111187F
Closed PbS nanowires with regular geometric morphologies (ellipse and parallelogram shape) were synthesized in the presence of poly[N-(2-aminoethyl)acrylamide] in ethylenediamine/H2O (3∶1, v/v) solvent at 110–150°C.
Co-reporter:Yuanfang Liu, Jinghui Zeng, Cun Li, Jinbo Cao, Yuanyuan Wang, Yitai Qian
Materials Research Bulletin 2002 Volume 37(Issue 15) pp:2509-2516
Publication Date(Web):1 December 2002
DOI:10.1016/S0025-5408(01)00808-X
Micron-sized rod-like crystals of Cu2−xSe were successfully grown for the first time by a hydrothermal reaction from CuCl2·2H2O and Se powder at 60°C for 2 h. X-ray powder diffraction patterns (XRD), X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM) images, and transmission electron microscope (TEM) images show that the product is cubic Cu2−xSe rod-like crystal and well crystallized. Hydrazine hydrate was used as solvent in the process and played an important role in the formation of rod-like Cu2−xSe crystals. The optical properties of Cu2−xSe, such as absorption spectra, photoluminescence (PL) spectra, and Raman spectrum are also reported for the first time.
Co-reporter:Yiya Peng, Zhaoyu Meng, Chang Zhong, Jun Lu, Zhiping Yang, Yitai Qian
Materials Chemistry and Physics 2002 Volume 73(2–3) pp:327-329
Publication Date(Web):15 January 2002
DOI:10.1016/S0254-0584(01)00364-9
Amorphous MoS2 was synthesized solvothermally in pyridine at 190 °C. XRD pattern indicated that the amorphous MoS2 was made up of single layer and layer stacking had not taken place. TEM images showed that tube- and ball-like morphologies existed in the amorphous MoS2. Electron diffraction did not reveal any crystal ordering in the tube and ball, which indicated that the tube and ball were completely amorphous. The influences of reaction conditions on the formation of these morphologies were also discussed. It was proposed that the formation of the tube- and ball-like structures might be energy-favorable for the single layer of MoS2 under the synthesis conditions.
Co-reporter:Dabin Yu, Weichao Yu, Debao Wang, Yitai Qian
Thin Solid Films 2002 Volume 419(1–2) pp:166-172
Publication Date(Web):1 November 2002
DOI:10.1016/S0040-6090(02)00482-0
This article reports on the fabrication of the Sn-doped In2O3 (ITO) films with corundum structure by a sol–gel route, using InCl3·4H2O, SnCl4 and de-ionized water as starting materials. Based on the hydrolysis of In3+ and Sn4+ in a solvothermal system using ethylenediamine as solvent, the aqueous sol was prepared, and acted as the precursor of the ITO films. The films were coated on quartz glass by the dip coating process, and annealed in air in the range of 350–750 °C. The structure, morphology, and composition of the films were investigated by X-ray powder diffraction, electron diffraction, transmission electron microscopy, scanning electron microscopy, and X-ray photoelectron spectrometer, indicating that the films were composed of ITO nanoparticles with corundum structure. The spectral transmittance of the films was measured in the wavelength range of 250–950 nm using an UV–vis spectrophotometer. The electrical resistivity of the films was measured by the four-probe method at room temperature. It was found that the optical and electrical properties of the films were affected significantly by the annealing temperature in the range of 350–580 °C due to the improvement of the crystallinity of the films with increasing temperature, and became stable when the annealing temperature was higher than 580 °C. The 6.8 at.% Sn-doped film annealed at 680 °C had high transmittance above 78% in wide visible range with maximum of 83% at 875 nm wavelength, and showed the lowest resistivity of 2.0×10−2 Ω cm.
Co-reporter:Jing-hui Zeng, Yu Zhu, Yuan-fang Liu, Jian Yang, Yi-tai Qian, Hua-gui Zheng
Materials Science and Engineering: B 2002 Volume 94(2–3) pp:131-135
Publication Date(Web):1 June 2002
DOI:10.1016/S0921-5107(01)00945-X
CdS/poly(vinyl acetate) (PVAc) composite was prepared by a hydrothermal polymerization and simultaneous sulfidation (HPSS) process. X-ray diffraction and transmission electron microscopy were used to characterize the products and study the morphology development. Composite spheres were prepared in the early stage of the process. Then the spheres stick with each other to form peanut-shaped morphology. Finally, composite rods are fully developed from the composite spheres. Fourier transform infrared spectroscopy was used to characterize the PVAc in the composite. Ultra violet–visible spectra were also recorded and the analysis suggests that the as-prepared CdS in the composite are quantum sized.
Co-reporter:Jing-hui Zeng, Jian Yang, Yu Zhu, Yuan-fang Liu, Yi-tai Qian and Hua-gui Zheng
Chemical Communications 2001 (Issue 15) pp:1332-1333
Publication Date(Web):04 Jul 2001
DOI:10.1039/B100632K
A hydrothermal polymerization and simultaneous sulfidation
(HPSS) process and the mechanism for the fabrication of one-dimensional
(1-D) nanocomposites of well dispersed CdS nanoparticles self-assembled in
the polymer nanorods is presented.
Co-reporter:Cheng-Xi Cao, Shu-Lin Zhou, Yi-Tai Qian, You-Zhao He, Li Yang, Qi-Shu Qu, Wen-Kui Chen
Journal of Chromatography A 2001 Volume 922(1–2) pp:283-292
Publication Date(Web):13 July 2001
DOI:10.1016/S0021-9673(01)00847-0
In this report, the moving chemical reaction boundary (MCRB) was formed with the weak acid of acetic acid (HAc) and the strong alkali of NaOH, coupled with the excess of background electrolyte KCl. The experiments were compared with the predictions by the moving chemical reaction boundary equation (MCRBE). It is very interesting that (1) the experimental results are in good agreement with the predictions with the original MCRBE if the MCRB is an anodic moving boundary, (2) however, the experiments are extremely far away from the predictions with the original MCRBE if a cathodic moving boundary. Hence, the original MCRBE must be corrected under the later situation of cathodic moving MCRB. The corrected MCRBE was well quantitatively proved to be valid for the cathodic moving MNRB formed with the same electrolytes of HAc, NaOH and KCl.
Co-reporter:Cheng-Xi Cao, Shu-Lin Zhou, You-Zhao He, Yi-Tai Qian, Li Yang, Qi-Shu Qu, Wu-Er Gan, Lin Dong, Yao-Qiang Zhao, Wen-Kui Chen
Journal of Chromatography A 2001 Volume 907(1–2) pp:347-352
Publication Date(Web):12 January 2001
DOI:10.1016/S0021-9673(00)01075-X
In this report, the moving chemical reaction boundary (MCRB) was formed by the weak reaction electrolytes of NH3·H2O and CH3COOH under the existence of background electrolyte KCl in large concentrations, the experiments were compared with the predictions by the moving chemical reaction boundary equation (MCRBE) for weak reactive electrolytes. It was found that the experimental results are far from the predictions with the MCRBE. So the MCRBEs must be corrected under the given experimental conditions. The corrected MCRBEs are given for the MCRB formed with weak reactive electrolytes coupled with KCl at high concentrations.
Co-reporter:Yuanfang Liu, Jinghua Zhan, Ming Ren, Kaibin Tang, Weichao Yu, Yitai Qian
Materials Research Bulletin 2001 Volume 36(7–8) pp:1231-1236
Publication Date(Web):May–June 2001
DOI:10.1016/S0025-5408(01)00614-6
In this paper, cadmium sulfide (CdS) square thin flakes were prepared from the aqueous solution of Cd(NO3)2 and thiocarbohydrate at 180°C by using surfactants. The resulting samples were characterized by powder X-ray diffraction (XRD) and transmission electron micrography (TEM). The particle prepared without surfactants has a spherical shape and the average size is about 16nm. The products fabricated in some surfactants have a square thin plate shape which may stack on each other to form a laminar structure. Electron diffraction (ED) indicated the samples were well crystallized.
Co-reporter:Jing-hui Zeng, Jian Yang, Yi-tai Qian
Materials Research Bulletin 2001 Volume 36(1–2) pp:343-348
Publication Date(Web):January 2001
DOI:10.1016/S0025-5408(01)00512-8
Mercury sulfide was synthesized by a controllable solvothermal method. X-ray diffraction, transmission electron microscopy and X-ray photoelectronic spectrum were used to characterize as-prepared mercury sulfides. Both hexagonal and cubic phase of mercury sulfide can be synthesized via this method. The phase transition of the two phases and the mechanism of morphology controlling in different solvents were studied. The results show that in the solvothermal reaction higher temperature is favorable for the phase transition from metacinnabar to cinnabar and polyamides play an important role in the forming of nanorods.
Co-reporter:Weixin Zhang, Zeheng Yang, Jinhua Zhan, Li Yang, Weichao Yu, Guien Zhou, Yitai Qian
Materials Letters 2001 Volume 47(Issue 6) pp:367-370
Publication Date(Web):February 2001
DOI:10.1016/S0167-577X(00)00268-8
Marcasite FeTe2 nanorods have been prepared through a hydrothermal method in alkaline aqueous solution in the temperature range of 120–170°C. XRD pattern of the product indicated that the product was orthorhombic FeTe2 with cell constants a=053 nm, b=0.63 nm and c=0.3 nm. Iron (II) complexes instead of iron (II) ion greatly reduced the amount of byproduct. The mechanism of the formation of iron ditelluride was discussed.
Co-reporter:Qing Li, Yi Ding, Xianming Liu, Yitai Qian
Materials Research Bulletin 2001 Volume 36(Issue 15) pp:2649-2656
Publication Date(Web):December 2001
DOI:10.1016/S0025-5408(01)00759-0
Cu- or Ag-containing ternary chalcogenides (Cu2SnS3, Cu2SnSe4, Ag8SnS6, and Ag8SnSe6) were prepared through a one-step solvothermal process in the temperature range of 150– 190°C. Three kinds of tin sources were investigated by changing the molar ratio, reaction time, and temperature. Powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electronic microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the products.
Co-reporter:Zhaohui Han, Xinyu Chen, Wanqun Zhang, Chang Zhong, Huaqiao Zhao, Yitai Qian
Materials Chemistry and Physics 2001 Volume 69(1–3) pp:292-294
Publication Date(Web):1 March 2001
DOI:10.1016/S0254-0584(00)00404-1
Using ethanol as the solvent, chemical reactions of ferric chloride and lithium hydroxide were studied under heated conditions. Crystallized β-LiFe5O8 and α-LiFeO2 were produced from the starting materials of different molar ratios. Owing to the incompleteness of reactions that occurred in the organic medium, an equilibrium between the two lithium ferrite phases was discovered. The reason for excess lithium source material for α-LiFeO2 was made clear by analyzing the chemical processes to the lithium ferrite.
Co-reporter:Weixin Zhang, Zeheng Yang, Xinmin Huang, Shuyuan Zhang, Weichao Yu, Yitai Qian, Yunbo Jia, Guien Zhou, Lin Chen
Solid State Communications 2001 Volume 119(Issue 3) pp:143-146
Publication Date(Web):17 July 2001
DOI:10.1016/S0038-1098(01)00231-9
Hydrothermal reaction of Bi(NO3)3·5H2O and Na2S·9H2O produces Bi2S3 nanorods in the temperature range of 100–170°C. X-ray powder diffraction (XRD) indicates that the product is orthorhombic Bi2S3 with cell constants and TEM images show that the product has the morphology of nanorods. Although Bi(NO3)3 is easily hydrolysed in water, the formation of bismuth sulfide under hydrothermal conditions using these starting materials is not inhibited. The mechanism of the formation of Bi2S3 is proposed.
Co-reporter:Cheng-Xi Cao, Ren-Zhi Li, Shu-Lin Zhuo, Wen-Kui Chen, Yi-Tai Qian
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2001 Volume 180(1–2) pp:17-21
Publication Date(Web):15 May 2001
DOI:10.1016/S0927-7757(00)00740-8
In this letter, we show the preparation of a stable colloid of Co(OH)2 in agarose gel by a novel synthetic method — the moving chemical reaction boundary method (MCRBM) and briefly show the results of experiments. The results obviously demonstrate that a stable colloid of Co(OH)2 can be prepared by the electromigration chemical reaction between cobaltic and hydroxyl ions in agarose gel, that the colloid sizes range from 100 to 400 nm, that the concentration of colloid, macroscopically, is uniform and controllable, and that, with the aid of MCRBM, a composite material can be further prepared.
Co-reporter:Yi Ding, Huazhang Zhao, Yugang Sun, Guangtao Zhang, Hao Wu, Yitai Qian
International Journal of Inorganic Materials 2001 Volume 3(Issue 2) pp:151-156
Publication Date(Web):March 2001
DOI:10.1016/S1466-6049(00)00105-7
Co-reporter:J. H. Zhan;X. G. Yang;D. W. Wang;S. D. Li;Y. Xie;Y. Xia;Y. Qian
Advanced Materials 2000 Volume 12(Issue 18) pp:
Publication Date(Web):14 SEP 2000
DOI:10.1002/1521-4095(200009)12:18<1348::AID-ADMA1348>3.0.CO;2-X
Co-reporter:Z.H Han, Y.P Li, J Lu, S.H Yu, H.Q Zhao, Y.T Qian
Materials Research Bulletin 2000 Volume 35(Issue 11) pp:1825-1829
Publication Date(Web):August 2000
DOI:10.1016/S0025-5408(00)00376-7
A series of late transition metal selenides were prepared within 180°C in ethylenediamine. Both anhydrous and hydrous starting materials could be used as long as the reducing oxalates were involved. As-prepared FeSe2, CoSe2, NiSe2, and Cu2−xSe crystallites were rod-like, disc-like, octahedral, and plate-like, respectively. Sulfides and tellurides of these late transition metals with different morphologies may also be synthesized by this preparative method.
Co-reporter:Z.H Han, Y.P Li, H.Q Zhao, S.H Yu, X.L Yin, Y.T Qian
Materials Letters 2000 Volume 44(Issue 6) pp:366-369
Publication Date(Web):July 2000
DOI:10.1016/S0167-577X(00)00060-4
Using copper(I) chloride, sodium oxalate and elemental chalcogen, copper chalcogenide powders were synthesized through a simple solvothermal route. Pseudocubic Cu1.80S and orthorhombic Cu31S16 single phases synthesized in ethylenediamine (En) are made up of polyhedral particles, cubic Cu2−xSe synthesized in pyridine (Py) was irregular in shape, while Cu1.75Te synthesized in distilled water appeared to be spherical. Other chalcogenides were also formed under different conditions.
Co-reporter:Weixin Zhang, Lei Zhang, Youwei Cheng, Zehua Hui, Xiaoming Zhang, Yi Xie, Yitai Qian
Materials Research Bulletin 2000 Volume 35(Issue 12) pp:2009-2015
Publication Date(Web):September 2000
DOI:10.1016/S0025-5408(00)00398-6
Reaction of a sulfur, selenium, or tellurium alkaline aqueous solution and Pb(CH3COO)2·3H2O aqueous solution produces nanocrystalline lead chalcogenides PbE (E = S, Se, or Te) with a cubic phase at low temperature under atmospheric pressure. The products are characterized through X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) analysis. The average particle size is in the range 20–35 nm. The XPS analysis indicates that the stability of the product surface in air decreases in the order PbS, PbSe, and PbTe. An advantage of this synthesis method is that the PbE crystallizes well in the alkaline solution. The mechanism for the formation of the lead chalcogenides is discussed.
Co-reporter:Yankuan Liu, Han Wang, Yongchun Zhu, Xiaoqing Wang, Xiaoyan Liu, Haibo Li, Yitai Qian
Solid State Communications (October 2009) Volume 149(37–38) pp:1514-1518
Publication Date(Web):1 October 2009
DOI:10.1016/j.ssc.2009.06.008
The concentration of the Mn(NO3)2 solution has significant influence on the morphologies and the phases of the MnO2 products. A large number of ε- MnO2 nanowires were prepared via a simple pyrolysis under lower reaction concentration. The nanowires have lengths up to tens of micrometers and diameters in the range of 20–100 nm. The β- MnO2 nanobundles and nanoflowers were prepared by increasing the concentration of Mn(NO3)2 solution. The superparamagnetism of ε- MnO2 nanowires and paramagnetism of β- MnO2 nanoflowers indicate their potential applications in magnetic materials.
Co-reporter:Junhao Zhang, Jin Du, Dekun Ma, Guangcheng Xi, Xiaobo Hu, Yitai Qian
Solid State Communications (October 2007) Volume 144(3–4) pp:168-173
Publication Date(Web):1 October 2007
DOI:10.1016/j.ssc.2007.06.026
Chain Fe3O4 nanoparticles encapsulated in worm-shaped carbon shell (defined as “WCCIOs”) were in situ synthesized by copyrolysis of polyethylene, malated-polypropylene and ferrocene in the presence of 10 ml H2O in an autoclave at 700 ∘C for 12 h. The shell thicknesses of these WCCIOs are about 180 nm and the lengths reach up to several micrometers. And the average size of the Fe3O4 nanoparticles inside the worm-shaped carbon shell is about 100 nm. The shapes and compositions of WCCIOs were simply controlled by adjusting the reaction temperatures and relative amounts of the precursors. On the basis of the experimental results, the formation process of the WCCIOs is discussed. The WCCIOs possess well acid resistance, which differs from those reported previously: the nanoparticles were embedded inside the thicker carbon shell. It is also found that the coercivity (Hc) value of the WCCIOs is much higher than that of bare Fe3O4 nanoparticles and bulk Fe3O4.
Co-reporter:Duoli Chai, XinSong Yuan, BaoJun Yang, Yitai Qian
Solid State Communications (December 2008) Volume 148(9–10) pp:444-447
Publication Date(Web):1 December 2008
DOI:10.1016/j.ssc.2008.09.018
Bismuth sulfide nanorods were synthesized on a large scale via a simple self-sacrificing template route, by the direct reaction between the pre-prepared precursor metallic bismuth NT arrays and thiourea (Tu) in air at 100 ∘C for 16 h. XRD, TEM, SEM and HRTEM characterizations show that the prepared Bi2S3 samples are all phase pure and the Bi2S3 nanorods have uniform diameters of approximately 30–50 nm and lengths up to several micrometers.
Co-reporter:Zhiguo Hou, Xueqian Zhang, Xiaona Li, Yongchun Zhu, Jianwen Liang and Yitai Qian
Journal of Materials Chemistry A 2017 - vol. 5(Issue 2) pp:NaN738-738
Publication Date(Web):2016/11/24
DOI:10.1039/C6TA08736A
Aqueous rechargeable batteries have received significant attention because of their low-cost and security. However, the narrow electrochemical stability window (about 1.23 V) of the aqueous electrolyte sets a limit on their energy output. Herein, we have developed an aqueous rechargeable hybrid battery using Na2MnFe(CN)6 nanocubes as the cathode and a zinc metal sheet as the anode, which delivered a high energy density of 170 W h kg−1 and a capacity retention of 75% over 2000 cycles with an operating voltage of up to 2.0 V. By adding sodium dodecyl sulfate (SDS) to the aqueous electrolyte, the electrochemical stability window of the electrolyte was expanded to about 2.5 V. The results of the experiments and calculations based on the density functional theory indicate that SDS can not only inhibit the decomposition of water, suppress the dissolution of Mn and the corrosion of zinc but also increase the cycle life and rate capability. The low-cost, high energy density, and long cycle life of the battery suggest that it is a promising candidate for energy storage applications.
Co-reporter:Ning Lin, Jie Zhou, Ying Han, Kailong Zhang, Yongchun Zhu and Yitai Qian
Chemical Communications 2015 - vol. 51(Issue 96) pp:NaN17159-17159
Publication Date(Web):2015/10/05
DOI:10.1039/C5CC06178D
Direct metathesis reaction between Mg2Ge and SnCl4 is introduced to prepare porous hierarchical Ge–Sn binary composites, in which the Ge and Sn components are distributed uniformly, with a tap density of 2.3 g cm−3. As an anode for LIBs, the Ge–Sn composite displays a specific capacity of 980 mA h g−1 at 0.5 A g−1 after 250 cycles, and 890 mA h g−1 at 3 A g−1 over 1700 cycles. When paired with a commercial LiCoO2 cathode, a 3.6 V full battery with a capacity of 830 mA h g−1 is obtained.
Co-reporter:Liangbiao Wang, Ning Lin, Jianbing Zhou, Yongchun Zhu and Yitai Qian
Chemical Communications 2015 - vol. 51(Issue 12) pp:NaN2348-2348
Publication Date(Web):2014/12/22
DOI:10.1039/C4CC09233C
Silicon (Si) nanoparticles have been prepared by a “metathesis” reaction of magnesium silicide (Mg2Si) and zinc chloride (ZnCl2) in an autoclave at 300 °C. The as-prepared Si nanoparticles exhibit a reversible capacity of 795 mA h g−1 at a current density of 3.6 A g−1 over 250 cycles.
Co-reporter:Xiaona Li, Jianwen Liang, Zhiguo Hou, Yongchun Zhu, Yan Wang and Yitai Qian
Chemical Communications 2015 - vol. 51(Issue 18) pp:NaN3885-3885
Publication Date(Web):2015/01/29
DOI:10.1039/C5CC00080G
A novel approach via reduction and carbonization of germanium chelate synchronously to in situ formed uniform Ge–carbon hybrid nanoparticles has been developed. The Ge–carbon composites, derived from the homogenous dispersion of the elements within the chelate complex matrix at the molecular level, exhibit outstanding electrochemical lithium-storage performance with high capacity, excellent rate capability, and ultra long cycling life.
Co-reporter:Jianwen Liang, Denghu Wei, Ning Lin, Youngchun Zhu, Xiaona Li, Jingjing Zhang, Long Fan and Yitai Qian
Chemical Communications 2014 - vol. 50(Issue 52) pp:NaN6859-6859
Publication Date(Web):2014/03/18
DOI:10.1039/C4CC00888J
Honeycomb porous silicon (hp-Si) has been synthesized by a low temperature (200 °C) magnesiothermic reduction of Na2SiO3·9H2O. This process can be regarded as a general synthesis method for other silicide materials. Significantly, hp-Si features excellent electrochemical properties after graphene coating.
Co-reporter:Xiaona Li, Jianwen Liang, Zhiguo Hou, Yongchun Zhu, Yan Wang and Yitai Qian
Chemical Communications 2014 - vol. 50(Issue 90) pp:NaN13959-13959
Publication Date(Web):2014/09/12
DOI:10.1039/C4CC06658H
A new (NH4)3H(Ge7O16)(H2O)2.72 precursor-pyrolyzation approach was designed and developed for the facile synthesis of nanostructured GeO2, avoiding the use of any hazardous or expensive germanium compounds. The products show promising anode application in lithium ion batteries with high capacity and excellent cycling stability.
Co-reporter:Zhiguo Hou, Xiaona Li, Jianwen Liang, Youngchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2015 - vol. 3(Issue 4) pp:NaN1404-1404
Publication Date(Web):2014/11/28
DOI:10.1039/C4TA06018K
Due to the costly short-term transients, frequency regulation, and load balancing, the electrical power grid faces an urgent need for large-scale energy storage. The long durability, high power and energy density, and low cost needed for stationary energy storage posing constant challenges for conventional battery technology inspire people to explore new kinds of energy storage technologies. Here, we assembled an aqueous rechargeable sodium ion battery by using NaMnO2 as a cathode material and NaTi2(PO4)3/C composites as anode materials in 2 M CH3COONa aqueous electrolyte. This battery system could work in a wide voltage range from 0.5 V to 1.8 V, giving an energy density of 30 W h kg−1 (based on the total mass of active materials) and could retain 75% of the initial capacity after 500 cycles at the 5 C rate. What is more, the earth-abundant precursors, environmental friendliness and inherent safety made this battery system particularly attractive for stationary energy storage applications.
Co-reporter:Kailong Zhang, Yanhua Xu, Yue Lu, Yongchun Zhu, Yuying Qian, Danfeng Wang, Jianbin Zhou, Ning Lin and Yitai Qian
Journal of Materials Chemistry A 2016 - vol. 4(Issue 17) pp:NaN6410-6410
Publication Date(Web):2016/03/22
DOI:10.1039/C6TA01118G
Composites of the graphene oxide-wrapped bipyramidal sulfur@polyaniline core–shell structure (S@PANI/GO) have been prepared at low temperature. The FT-IR and Raman spectra illustrated the chemical effect between PANI and GO, and the SEM images illustrated the tight connection with each other. As a cathode for Li–S batteries, the S@PANI/GO composite demonstrated better electrochemical performance than S@PANI, or S/GO composites. The S@PANI/GO composite delivered enhanced cycle stability (0.2 C, 875 mA h g−1 after 100 cycles) and high-rate capability (4 C, 466 mA h g−1). Even at 1 C, the S@PANI/GO composite still delivered a capacity of 641 mA h g−1 after 300 cycles. The enhanced performance should benefit from the core–shell structure with a synergistic effect between polyaniline and graphene oxide.
Co-reporter:Long Fan, Jingjing Zhang, Jianhua Cui, Yongchun Zhu, Jianwen Liang, Lili Wang and Yitai Qian
Journal of Materials Chemistry A 2015 - vol. 3(Issue 7) pp:NaN3280-3280
Publication Date(Web):2015/01/14
DOI:10.1039/C4TA06771A
Rod-like Sb–C composite has been synthesized by a synchronous reduction and carbon deposition process. The Sb–C composite anode exhibits a reversible capacity of 478.8 mA h g−1 at 100 mA g−1 after 100 cycles for Li-ion batteries and exhibits a reversible capacity of 430.9 mA h g−1 at 50 mA g−1 after 100 cycles for Na-ion batteries.
Co-reporter:Ning Lin, Liangbiao Wang, Jianbin Zhou, Jie Zhou, Ying Han, Yongchun Zhu, Yitai Qian and Changhe Cao
Journal of Materials Chemistry A 2015 - vol. 3(Issue 21) pp:NaN11202-11202
Publication Date(Web):2015/04/17
DOI:10.1039/C5TA02216A
A Si/Ge nanocomposite composed of interconnected Si and Ge nanoparticles is prepared through a one-step solid-state metathesis reaction between Mg2Si and GeO2 for the first time. As an anode, the Si/Ge electrode exhibits a reversible capacity of 2404.7 mA h g−1 at 0.5 A g−1 over 60 cycles and long-term cycling stability with a capacity of 1260 mA h g−1 over 500 cycles even at 5 A g−1.
Co-reporter:Lulu Si, Zhengqiu Yuan, Jianwen Liang, Lei Hu, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2014 - vol. 2(Issue 25) pp:NaN9791-9791
Publication Date(Web):2014/04/30
DOI:10.1039/C4TA01234H
Carbon-coated one-dimensional (1-D) SnO2/MoO3 nanostructure (SnO2/MoO3/C) composed of densely stacked SnO2 nanosheets, uniformly distributing in amorphous MoO3 matrix, is obtained from the 1-D SnO2/MoO3 heterostructure, which is prepared for the first time by a facile, one-pot hydrothermal method. The precursor 1-D SnO2/MoO3 heterostructure is composed of SnO2 nanosheets, adhering to the two edges of 1-D MoO3 nanobelt by lattice matching between the (140) plane of orthorhombic MoO3 and (110) plane of rutile SnO2. By prolonging the hydrothermal reaction time, the as-obtained 1-D SnO2/MoO3 heterostructure is converted to a novel 1-D nanostructure, amorphous MoO3 that deposits uniformly on the surface of the SnO2 nanosheets with the preservation of the front SnO2 1-D architecture. For optimizing performance, 1-D SnO2/MoO3/C nanostructure is obtained by carbon coating on the surface of the novel 1-D nanostructure MoO3/SnO2via the pyrolysis of acetylene. Because of the 1-D nanostructure composed of nanosheets and the carbon matrix, the SnO2/MoO3/C nanocomposites exhibit an outstanding high-rate cycling performance, delivering a reversible discharge capacity of more than 560 mA h g−1 after 120 cycles at a high current density of 200 mA g−1.
Co-reporter:Jie Yue, Xin Gu, Liang Chen, Nana Wang, Xiaolei Jiang, Huayun Xu, Jian Yang and Yitai Qian
Journal of Materials Chemistry A 2014 - vol. 2(Issue 41) pp:NaN17426-17426
Publication Date(Web):2014/08/27
DOI:10.1039/C4TA03924F
The use of manganese oxides as promising candidates for anode materials in lithium ion batteries has attracted a significant amount of attention recently. Here, we develop a general approach to synthesize hollow nanospheres of MnO2, Mn3O4 and MnO, using carbon nanospheres as a template and a reagent. Depending on the calcination temperature, time and atmosphere, hollow nanospheres of MnO2 assembled by randomly dispersed nanosheets, or hollow nanospheres of Mn3O4 and MnO composed of aggregated nanoparticles, are produced. The electrochemical properties of the three hollow nanoparticles are investigated in terms of cycling stability and rate capability. They deliver the specific capacities of 840, 1165 or 1515 mA h g−1 after 60 cycles at 100 mA g−1 for MnO2, Mn3O4 and MnO. Even at 500 mA g−1, the reversible capacities could be still kept at 637, 820, and 1050 mA h g−1 after 150 cycles. The outstanding performances might be related with their hollow structure, porous surface and nanoscale size.
Co-reporter:Ning Lin, Jianbin Zhou, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2014 - vol. 2(Issue 46) pp:NaN19608-19608
Publication Date(Web):2014/10/08
DOI:10.1039/C4TA05089D
A Si/reduced graphene oxide composite with 3D framework is constructed by a typical cross-linking reaction between polyacrylamide and graphene oxides, which delivers a high reversible capacity of 1610 mA h g−1 at 1.2 A g−1 after 200 cycles, good rate capability, and cycling stability with negligible capacity degradation over 200 cycles.
Co-reporter:Linlin Wang, Wei Cheng, Huaxu Gong, Caihua Wang, Dake Wang, Kaibin Tang and Yitai Qian
Journal of Materials Chemistry A 2012 - vol. 22(Issue 22) pp:NaN11302-11302
Publication Date(Web):2012/03/30
DOI:10.1039/C2JM31023F
In this work, nanocrystalline-assembled bundle-like CuO structures were successfully synthesized in large-quantity by a friendly, facile two-step process. The bundle-like CuO particles are produced by thermolysis of bundle-like Cu(OH)2 precursors, which exhibit excellent high specific capacity, high stability, and especially high rate performance for anode materials in lithium-ion batteries, superior to that of most reported CuO-based anodes. The assembled structure of CuO endows it with high rate capacities of 666 mAh g−1, 609 mAh g−1, and 499 mAh g−1 at a current rate of 0.3 C, 1 C and 2 C after 50 cycles, respectively. Even at a high rate of 6 C, the bundle-like CuO can still deliver a capacity of 361 mAh g−1. It is observed that the electrochemical performance of the nanocrystalline-assembled bundle-like CuO is much better than that of CuO nanoparticles obtained by destroying the assembled bundle-like CuO through grinding. XRD analysis of both the electrodes after ending the discharge/charge proved that during the discharge/charge process, the conversion reactions occurring in the assembled structures have better reversibility, leading to the high rate capacity and cycling performances. The better reversibility originates from the better contact area for CuO/electrolyte, enhancing many sites to the access of Li+ in the electrolyte Li+. In addition, the assembled bundle-like CuO architectures can also relieve the volume variations during the Li+ uptake–release process, which also contributes to the excellent electrochemical performance. The high rate capacity and enhanced cycling stability of the bundle-like CuO structure make it a promising candidate as an anode material for high-performance Li-ion batteries.
Co-reporter:Xing Zhang, Zheng Xing, Lili Wang, Yongchun Zhu, Qianwen Li, Jianwen Liang, Yang Yu, Tao Huang, Kaibin Tang, Yitai Qian and Xiaoyan Shen
Journal of Materials Chemistry A 2012 - vol. 22(Issue 34) pp:NaN17869-17869
Publication Date(Web):2012/07/13
DOI:10.1039/C2JM32421K
MnO@C core–shell nanoplates with a size of ∼150 nm have been prepared via thermal treatment deposition of acetylene with the precursor of Mn(OH)2 nanoplates, which has been hydrothermally synthesized. The thickness of the carbon shells varied from ∼3.1 to 13.7 nm by controlling the treatment temperature and reaction duration time. The electrochemical performance of the MnO@C nanoplates, which were synthesized at 550 °C for 10 h with a carbon shell thickness of ∼8.1 nm, display a high reversible capacity of ∼770 mA h g−1 at a current density of 200 mA g−1 and good cyclability after prolonged testing, which is higher than that of MnO@C nanoplates with a carbon shell thickness of ∼3.1, 4.0, 4.2, 10.9 and 13.7 nm.
Co-reporter:Yongchun Zhu, Tao Mei, Yan Wang and Yitai Qian
Journal of Materials Chemistry A 2011 - vol. 21(Issue 31) pp:NaN11463-11463
Publication Date(Web):2011/06/22
DOI:10.1039/C1JM11079A
Formation and morphology control of nanomaterials is a crucial issue in nanoscience research in the exploitation of novel properties. This article presents a review of some research activities on the formation and morphology control of nanoparticlesvia solution routes in an autoclave over the last decade. Several solution systems, including hydrothermal, solvothermal and mixed solvothermal routes, are specifically discussed and highlighted. A helical belt template mechanism was proposed for the formation of the Te nanotubes in aqueous ammonia. Assisted by the surfactant of sodium dodecyl benzenesulfonate (SDBS), nickel nanobelts were hydrothermally synthesized. Ethylenediamine (En) and n-butylamine can be used as shape controllers to one-dimensional (1D) semiconductor nanostructures in the solvothermal process. The phase of metastable and stable MnS crystallites can be controlled by solvothermal reaction in various solvents. Selective preparation of 1D to 3D CdS nanostructures was achieved by controlling the volume ratio of the mixed solvents. With poly(vinylpyrrolidone) (PVP) serving as a soft template, the transformation from nanowires to nanotubes, then to nanowires was observed in the mixed solvents of distilled water and ethanolamine (EA).
Co-reporter:Qianqian Yang, Jie Zhou, Genqiang Zhang, Cong Guo, Meng Li, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2017 - vol. 5(Issue 24) pp:NaN12148-12148
Publication Date(Web):2017/05/17
DOI:10.1039/C7TA03060F
Sb nanoparticles encapsulated in 1-D N-doped porous carbon (denoted as Sb/NPC) have been fabricated by an in situ nanoconfined replacement reaction between SbCl3 and the intermediate Ni/NPC, in which Ni/NPC was obtained by annealing the hydrothermally synthesized nickel–nitrilotriacetic acid (Ni–NTA) precursor in an argon atmosphere. The Sb nanoparticles with a size of 10–20 nm were uniformly encapsulated in the 1-D N-doped porous carbon scaffolds. When the Sb/NPC composite was applied as an anode material in the batteries, it exhibited a high reversible capacity of 556 mA h g−1 at 200 mA g−1 after 100 cycles for Li-ion batteries (LIBs) and a reversible capacity of 400.9 mA h g−1 at 100 mA g−1 after 100 cycles for Na-ion batteries (NIBs). Such enhanced electrochemical performance of the designed Sb/NPC can be attributed to the synergistic effect between uniformly dispersed Sb nanoparticles and the 1-D N-doped porous carbon matrices.
Co-reporter:Jianbin Zhou, Ning Lin, Liangbiao Wang, Kailong Zhang, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2015 - vol. 3(Issue 14) pp:NaN7468-7468
Publication Date(Web):2015/02/25
DOI:10.1039/C5TA00516G
Hexagonal MoO3 nanorods with an average diameter of 40 nm have been synthesized in an immiscible mixture of water and methylbenzene. Both citric acid, which can chelate molybdic acid in water solution, and the interface reaction occurring between the two phases of the mixture are favorable for the formation of hexagonal MoO3 nanorods. As an anode material for lithium-ion batteries, hexagonal MoO3 nanorods exhibit a capacity of over 780 mA h g−1 after 150 cycles at 150 mA g−1, which is higher than that of hexagonal MoO3 microrods with diameters of 2–3 μm.
Co-reporter:Qiushi Cheng, Jianwen Liang, Yongchun Zhu, Lulu Si, Cong Guo and Yitai Qian
Journal of Materials Chemistry A 2014 - vol. 2(Issue 41) pp:NaN17262-17262
Publication Date(Web):2014/09/03
DOI:10.1039/C4TA04184D
Ti2Nb10O29 is fabricated directly by solid-state reaction from commercial TiO2 and Nb2O5. Without further modification, the bulk Ti2Nb10O29 anode exhibits a reversible capacity of 144 mA h g−1 at 10 C after 800 cycles. More impressively, the capacity of the Ti2Nb10O29/LiFePO4 full-cell at 1 C stabilizes at 100 mA h g−1 after 1000 cycles.
Co-reporter:Yongchun Zhu, Qianwen Li, Tao Mei and Yitai Qian
Journal of Materials Chemistry A 2011 - vol. 21(Issue 36) pp:NaN13764-13764
Publication Date(Web):2011/07/21
DOI:10.1039/C1JM11893E
This feature article provides a brief overview of the latest developments in the solid state synthesis of various nitride, carbide and boride nanocrystals in an autoclave at mild temperatures. An additive assisted route was developed for nitride, carbide and boride nanocrystals. In the presence of S powder, 3C–SiC nanocrystals were obtained utilizing waste plastics and Si powder at 350–500 °C. With the assistance of I2, rare-earth and alkaline-earth hexaboride nanocrystals were prepared at temperatures below 400 °C. As N-aminothiourea and iodine were added to the system containing Si and NaN3, β-Si3N4 nanorods and α,β-Si3N4 nanoparticles could be prepared at 60 °C. A ternary nitride of MgSiN2 can also be prepared at 350–500 °C using Si, Mg, and NaN3 as reactants.
Co-reporter:Xueqian Zhang, Zhiguo Hou, Xiaona Li, Jianwen Liang, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2016 - vol. 4(Issue 3) pp:NaN860-860
Publication Date(Web):2015/11/27
DOI:10.1039/C5TA08857G
Layer structure Na-birnessite (Na-Bir) Na0.58MnO2·0.48H2O has been synthesized through a precipitation reaction at room temperature and used as a rechargeable aqueous sodium-ion battery (RASIB) cathode material for the first time. As a RASIB cathode material, the layered Na-birnessite manifests a high specific capacity of 80 mA h g−1 at 1C without obvious capacity loss after 150 cycles. After heat treatment of the Na-Bir sample, it can deliver a specific capacity of 79 mA h g−1 at 1C but only retains 60% of the initial capacity after 150 cycles. The XRD analysis of the Na-Bir sample after 150 cycles reveals that the layer structure is retained, while inductively coupled plasma atomic emission spectroscopy (ICP-AES) indicates that the dissolution of Mn is merely 0.008 wt% of Na-Bir after 150 cycles. As a cathode electrode in full batteries coupled with a NaTi2(PO4)3 anode electrode, a high capacity of 39 mA h g−1 at 10C is obtained with a capacity retention of 94% after 1000 cycles.
Co-reporter:Tao Mei, Kaibin Tang, Yongchun Zhu and Yitai Qian
Dalton Transactions 2011 - vol. 40(Issue 29) pp:NaN7650-7650
Publication Date(Web):2011/06/24
DOI:10.1039/C1DT10228A
LiCoO2 concaved cuboctahedra with a size of about 1.0 μm were hydrothermally prepared from CoCO3 and LiOH·H2O at 150 °C. Field-emitting scanning electron microscope (FESEM) images show that the cuboctahedra consisted of four hexagonal plates, with angles of 70.5° in neighboring plates. Electron diffraction (ED) patterns of the hexagonal plates show 100 diffraction of LiCoO2 in rhombohedral phase and 220 diffraction in spinel phase, which means LiCoO2 concaved cuboctahedra are comprised of two intergrown phases. The electrochemical performance of these concaved cuboctahedra of LiCoO2 at a rate of 0.5 C demonstrated first run charge/discharge capacities of 155 and 141 mAh g−1 and a stable discharge capacity of 114 mAh g−1 after 100 cycles. After that, FESEM images show the LiCoO2 concaved cuboctahedra have undergone no significant change. At a temperature of 120 °C and under the same conditions, only a small amount of LiCoO2 concaved cuboctahedron appeared. As the temperature rose to 180 °C, flower-like LiCoO2 microstructures with a size of about 1.0 μm were formed, constructed of irregular plates. The electrochemical performance of the products prepared at 120 °C and 180 °C indicates lower stability than that of LiCoO2 concaved cuboctahedra.
Co-reporter:Ning Lin, Jie Zhou, Jianbin Zhou, Ying Han, Yongchun Zhu and Yitai Qian
Journal of Materials Chemistry A 2015 - vol. 3(Issue 34) pp:NaN17548-17548
Publication Date(Web):2015/07/29
DOI:10.1039/C5TA04354A
Commercial micron-sized bulk Si is chemically converted into a nano-sized Si/Cu/C ternary composite. The Si particles, Cu crystals, and amorphous carbon are generated synchronously and mixed uniformly. As an anode, the Si/Cu/C exhibits a capacity of 1560 mA h g−1 after 80 cycles at 0.5 mA g−1, long-term cycling stability with a capacity of 757 mA h g−1 at 2 A g−1 after 600 cycles, and fine rate capability.
Co-reporter:Jingjing Zhang, Jianwen Liang, Yongchun Zhu, Denghu Wei, Long Fan and Yitai Qian
Journal of Materials Chemistry A 2014 - vol. 2(Issue 8) pp:NaN2734-2734
Publication Date(Web):2013/12/10
DOI:10.1039/C3TA13228E
A Co2SnO4 hollow cube/graphene composite (Co2SnO4 HC@rGO) was synthesized by pyrolysis-induced transformation from the hydrothermally synthesized hollow cubic precursor and subsequent combination with graphene sheets via the analogous mechanism of electrostatic interactions. The Co2SnO4 HCs with a size of 240 nm and the shell of 50–70 nm thickness were uniformly encapsulated in the graphene sheets. As an anode material for lithium-ion batteries, the Co2SnO4 HC@rGO exhibited significantly enhanced cyclability and superior rate capability compared to the pure Co2SnO4 counterpart. Even after 100 cycles, it still delivered a capacity over 1000 mA h g−1 at 100 mA g−1.
Co-reporter:Linlin Wang, Wanqun Zhang, Caihua Wang, Dake Wang, Zhongping Liu, Qiaoyan Hao, Yan Wang, Kaibin Tang and Yitai Qian
Journal of Materials Chemistry A 2014 - vol. 2(Issue 14) pp:NaN4974-4974
Publication Date(Web):2014/01/17
DOI:10.1039/C3TA14563H
CdSnO3 materials have been extensively studied as gas-sensing materials. However, there are few reports on the synthesis and use of porous CdSnO3 nanostructures for energy storage. Herein, we report highly porous CdSnO3 nanoparticles prepared using citric acid with sizes in the range of ∼7.8 nm to 28.7 nm and the application of these nanoparticles as an anode material for rechargeable Li-ion batteries (LIBs). Electrochemical measurements showed that the highly porous CdSnO3 nanoparticles delivered a high reversible capacity of ∼515 mA h g−1 for up to 40 cycles at a current rate of 70 mA g−1. Even at a high rate of 150 mA g−1, the porous CdSnO3 could still deliver a capacity of 506 mA h g−1. It is observed that the electrochemical performance of the highly porous CdSnO3 nanoparticles is much better than that (∼370 mA h g−1 for up to 40 cycles) of a counterpart obtained without citric acid, which also demonstrates the capacity enhancement and high rate capacity.
Co-reporter:Jianwen Liang, Xiaona Li, Zhiguo Hou, Cong Guo, Yongchun Zhu and Yitai Qian
Chemical Communications 2015 - vol. 51(Issue 33) pp:NaN7233-7233
Publication Date(Web):2015/03/19
DOI:10.1039/C5CC01659B
Nanoporous silicon has been prepared through the air-oxidation demagnesiation of Mg2Si at 600 °C for 10 hours (Mg2Si + O2 → Si + MgO), followed by HCl washing. Mg2Si was prepared from 200 mesh commercial Si at 500 °C for 5 h in an autoclave. The as-prepared Si exhibits a reversible capacity of 1000 mA h g−1 at 36 A g−1 and ∼1200 mA h g−1 at 1.8 A g−1 over 400 cycles.
Co-reporter:Ying Han, Ning Lin, Yuying Qian, Jianbin Zhou, Jie Tian, Yongchun Zhu and Yitai Qian
Chemical Communications 2016 - vol. 52(Issue 19) pp:NaN3816-3816
Publication Date(Web):2016/02/04
DOI:10.1039/C6CC00253F
N-doped Si nanoparticles were prepared synchronously by nitridation of Mg2Si. The existence of nitrogen doping can be demonstrated by the XPS spectrum and EELS energy-filtered images. When the N-doped Si nanoparticles were used as an anode for Li-ion batteries, a high reversible capacity of 2595 mA h g−1 at 0.36 A g−1 after 40 cycles, and 805 mA h g−1 at 3.6 A g−1 after 800 cycles could be obtained.
