Co-reporter:Dong Wang;Rui Zhang;Jieying Li;Xiaojing Hao;Chunyan Ding;Limin Zhao;Guangwu Wen;Weiwei Zhou
Journal of Materials Chemistry A 2017 vol. 5(Issue 4) pp:1687-1697
Publication Date(Web):2017/01/24
DOI:10.1039/C6TA07936A
Engineering two transition metals into an integrated spinel oxide anode provides great opportunity towards high-performance lithium-ion batteries (LIBs). Spinels with high-valence transition metal oxides (TMOs) however tend to exhibit low initial coulombic efficiency (ICE) due to the irreversible Li2O generated during the first discharge process. Herein, we report a simple and general strategy to synthesize elaborate graphene framework (GF) supported low-valence bicomponent transition metal monoxide anodes (e.g., ZnO–MnO microcubes, ZnO–CoO polyhedra, NiO–CoO nanowires, and (FeO)0.333(MnO)0.667 microspheres, etc.), which can efficiently address the low ICE issue. As a proof of concept demonstration, we show that the ZnO–MnO/GF is indeed more advantageous as an LIB anode over the spinel ZnMn2O4/GF counterpart as well as many other ZnMn2O4-based anodes. Benefiting from the enhanced reversibility of Li+ uptake/extraction and graphene hybridization, the ZnO–MnO/GF electrode exhibits significantly improved ICEs at various current densities, superior rate capability (286 mA h g−1 even at a high current density of 6 A g−1; ∼2.9 min charging/discharging), and extended cycling life (1123 mA h g−1 after 300 cycles) with respect to ZnMn2O4/GF. Such improvements have also been observed for the ZnO–CoO/GF electrode and other analogues. This versatile electrode design could advance our understanding and control of complex TMO-based anodes to gain high ICE and capacity.
Co-reporter:Yanfang Mao, Shunhua Xiao, Jinping Liu
Materials Research Bulletin 2017 Volume 96, Part 4(Volume 96, Part 4) pp:
Publication Date(Web):1 December 2017
DOI:10.1016/j.materresbull.2017.03.005
•The LiMn2O4 hollow microspheres are assembled by LiMn2O4 octahedral nanoparticles.•The LiMn2O4 hollow microspheres exhibit larger diffusion coefficient and better rate performance.•The LiMn2O4 hollow microspheres display longer cycling stability.Spinel LiMn2O4 is an attractive cathode material for rechargeable lithium-ion batteries. However, its cycling and rate performance need further improvement. Herein, we present a novel LiMn2O4 hollow microsphere cathode fabricated via a simple solid-state reaction utilizing MnO2 hollow microspheres and LiOHH2O as the reactants. Interestingly, the as-prepared LiMn2O4 hollow microspheres are assembled by LiMn2O4 octahedral nanoparticles with exposed {111} planes, exhibiting abundant void spaces for the stress buffering and larger diffusion coefficient (1.570 × 10−7 cm2 s−1) for fast lithium ion transfer as compared to the simply aggregated LiMn2O4 nanoparticles. As a result, the LiMn2O4 hollow microspheres exhibit much improved cycling stability and deliver a specific discharge capacity of 86.3 mAh g−1 at a high rate of 10C, higher than that of the aggregated LiMn2O4 (73.9 mAh g−1). Our work suggests that the electrochemical performance of LiMn2O4 cathode can be manipulated by the design of unique hollow sphere structure.Download high-res image (196KB)Download full-size image
Co-reporter:Weihua Zhu;Ruizhi Li;Pan Xu;Yuanyuan Li
Journal of Materials Chemistry A 2017 vol. 5(Issue 42) pp:22216-22223
Publication Date(Web):2017/10/31
DOI:10.1039/C7TA07036E
Direct synthesis of large-scale electrode nanostructures on flexible current collectors is crucial to realize high-performance emerging flexible supercapacitors (SCs). However, three-dimensional (3D) macroporous and thick current collectors such as carbon cloth/foam were mostly utilized in previous studies. These 3D current collectors unfortunately wasted much internal space (tens of micrometer interspacing), resulting in quite low volumetric energy density of the flexible SC devices. To address this issue, herein, we choose highly conductive pseudocapacitive vanadium trioxide (V2O3) as an example and report for the first time the growth of a V2O3@carbon nanosheet array directly on a 10 μm ultrathin Ti current collector on a 600 cm2 scale through a hydrothermal & post-annealing strategy. The array is further utilized to assemble a symmetric ultrathin (40 μm) flexible quasi-solid-state SC with the integration of polyvinyl alcohol (PVA)–LiCl gel electrolyte. With different redox reactions of vanadium ions in the anode and cathode, our symmetric hydrogel SC achieved an exceptional cell voltage of 2.0 V, outstanding rate performance (∼47.2% capacitance retention with the rate increasing 80 times) and remarkable volumetric energy and power densities of 15.9 mW h cm−3 and 6800 mW cm−3, respectively (without considering the encapsulation film). It also exhibits excellent cycling stability (>6000 times) and ∼100% capacitance retention at various bending states.
Co-reporter:Wenhua Zuo;Ruizhi Li;Cheng Zhou;Yuanyuan Li;Jianlong Xia
Advanced Science 2017 Volume 4(Issue 7) pp:
Publication Date(Web):2017/07/01
DOI:10.1002/advs.201600539
Design and fabrication of electrochemical energy storage systems with both high energy and power densities as well as long cycling life is of great importance. As one of these systems, Battery-supercapacitor hybrid device (BSH) is typically constructed with a high-capacity battery-type electrode and a high-rate capacitive electrode, which has attracted enormous attention due to its potential applications in future electric vehicles, smart electric grids, and even miniaturized electronic/optoelectronic devices, etc. With proper design, BSH will provide unique advantages such as high performance, cheapness, safety, and environmental friendliness. This review first addresses the fundamental scientific principle, structure, and possible classification of BSHs, and then reviews the recent advances on various existing and emerging BSHs such as Li-/Na-ion BSHs, acidic/alkaline BSHs, BSH with redox electrolytes, and BSH with pseudocapacitive electrode, with the focus on materials and electrochemical performances. Furthermore, recent progresses in BSH devices with specific functionalities of flexibility and transparency, etc. will be highlighted. Finally, the future developing trends and directions as well as the challenges will also be discussed; especially, two conceptual BSHs with aqueous high voltage window and integrated 3D electrode/electrolyte architecture will be proposed.
Co-reporter:Wenhua Zuo;Chaoyue Xie;Pan Xu;Yuanyuan Li
Advanced Materials 2017 Volume 29(Issue 36) pp:
Publication Date(Web):2017/09/01
DOI:10.1002/adma.201703463
One of the key challenges of aqueous supercapacitors is the relatively low voltage (0.8–2.0 V), which significantly limits the energy density and feasibility of practical applications of the device. Herein, this study reports a novel Ni–Mn–O solid-solution cathode to widen the supercapacitor device voltage, which can potentially suppress the oxygen evolution reaction and thus be operated stably within a quite wide potential window of 0–1.4 V (vs saturated calomel electrode) after a simple but unique phase-transformation electrochemical activation. The solid-solution structure is designed with an ordered array architecture and in situ nanocarbon modification to promote the charge/mass transfer kinetics. By paring with commercial activated carbon anode, an ultrahigh voltage asymmetric supercapacitor in neutral aqueous LiCl electrolyte is assembled (2.4 V; among the highest for single-cell supercapacitors). Moreover, by using a polyvinyl alcohol (PVA)–LiCl electrolyte, a 2.4 V hydrogel supercapacitor is further developed with an excellent Coulombic efficiency, good rate capability, and remarkable cycle life (>5000 cycles; 95.5% capacity retention). Only one cell can power the light-emitting diode indicator brightly. The resulting maximum volumetric energy density is 4.72 mWh cm−3, which is much superior to previous thin-film manganese-oxide-based supercapacitors and even battery–supercapacitor hybrid devices.
Co-reporter:Liang Xiao, Shiyao Wang, Yafei Wang, Wen Meng, Bohua Deng, Deyu Qu, Zhizhong Xie, and Jinping Liu
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 38) pp:25369
Publication Date(Web):September 6, 2016
DOI:10.1021/acsami.6b09022
Manganese carbonate (MnCO3) is an attractive anode material with high capacity based on conversion reaction for lithium-ion batteries (LIBs), but its application is mainly hindered by poor cycling performance. Building nanostructures/porous structures and nanocomposites has been demonstrated as an effective strategy to buffer the volume changes and maintain the electrode integrity for long-term cycling. It is widely believed that microsized MnCO3 is not suitable for use as anode material for LIBs because of its poor conductivity and the absence of nanostructure. Herein, different from previous reports, spherical MnCO3 with the mean diameters of 6.9 μm (MnCO3–B), 4.0 μm (MnCO3–M), and 2.6 μm (MnCO3–S) were prepared via controllable precipitation and utilized as anode materials for LIBs. It is interesting that the as-prepared MnCO3 microspheres demonstrate both high capacity and excellent cycling performance comparable to their reported nanosized counterparts. MnCO3–B, MnCO3–M, and MnCO3–S deliver reversible specific capacities of 487.3, 573.9, and 656.8 mA h g–1 after 100 cycles, respectively. All the MnCO3 microspheres show capacity retention more than 90% after the initial stage. The advantages of MnCO3 microspheres were investigated via constant-current charge/discharge, cyclic voltammetry and electrochemical impedance spectroscopy. The results indicate that there should be substantial structure transformation from microsized particle to self-stabilized nanostructured matrix for MnCO3 at the initial charge/discharge stage. The evolution of EIS during charge/discharge clearly indicates the formation and stabilization of the nanostructured matrix. The self-stabilized porous matrix maintains the electrode structure to deliver excellent cycling performance, and contributes extra capacity beyond conversion reaction.Keywords: anode material; lithium-ion batteries; manganese carbonate; microspheres; self-stabilization
Co-reporter:Yuanyuan Li, Fan Tang, Renjie Wang, Chong Wang, and Jinping Liu
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 44) pp:30232
Publication Date(Web):October 24, 2016
DOI:10.1021/acsami.6b10249
Cobalt/nickel-based compounds have been extensively used as cathode (positive electrode) materials in alkaline electrolyte for hybrid supercapacitors (HSCs). In these HSCs, however, the anodes (negative electrodes) are almost carbon-based materials that exhibit limited capacitance, leading to relatively low energy density of the device. Herein, we report a novel dual-ion HSC concept, that is, utilizing anion and cation in the electrolyte, respectively, by the two electrodes for charge storage, to promote the device’s performance. Based on this, it is possible to exploit cation-consumed metal oxide as a capacitive anode to couple with a cobalt/nickel oxide cathode. As a demonstration, a 1.8 V MoO2–C/LiOH electrolyte/NiCo2O4 HSC device is established. In such a design, NiCo2O4 cathode and MoO2–C anode react with OH– and Li+, respectively, to store energy. With the benefits from enhanced kinetics in NiCo2O4 nanowire array (direct electron transport pathway and sufficient electrolyte/ion penetration) and increased stability and electrical conductivity in carbon-encapsulated MoO2 nanofilm, our device delivers a high capacitance (94.9 F g–1), high energy density and power density (41.8 Wh kg–1 and 19922.2 W kg–1), long cycling stability >3000 times, and good rate capability (∼3.3 s charging/discharging with 43.6% capacitance retention). The dual-ion charge storage concept will stimulate great interest in the design of high-performing all-oxide hybrid electric energy storage systems.Keywords: dual-ion charge storage; hybrid supercapacitor; molybdenum dioxide; nanostructured electrode; nickel cobaltite
Co-reporter:Ruizhi Li, Zhijun Lin, Xin Ba, Yuanyuan Li, Ruimin Ding and Jinping Liu
Nanoscale Horizons 2016 vol. 1(Issue 2) pp:150-155
Publication Date(Web):09 Dec 2015
DOI:10.1039/C5NH00100E
An integrated (Cu,Ni)O mesoporous nanowire array was fabricated by a simple hydrothermal method with subsequent annealing, which with optimized Cu:Ni ratio = 1:1 delivers a high specific capacitance of 1710 F g−1. The further assembled aqueous asymmetric supercapacitor (Cu,Ni)O(+)//activated carbon(−) demonstrates high energy/power densities and long cycle life.
Co-reporter:Ruizhi Li, Xin Ba, Yimeng Wang, Wenhua Zuo, Chong Wang, Yuanyuan Li, Jinping Liu
Progress in Natural Science: Materials International 2016 Volume 26(Issue 3) pp:258-263
Publication Date(Web):June 2016
DOI:10.1016/j.pnsc.2016.05.003
To enhance the electrochemical energy storage performance of supercapacitors (SCs), the current researches are general directed towards the cathode materials. However, the anode materials are relatively less studied. In the present work, Fe3O4-MoO2 (FO-MO) hybrid nano thin film directly grown on Ti substrate is investigated, which is used as high-performance anode material for SCs in Li2SO4 electrolyte with the comparison to pristine Fe3O4 nanorod array. The areal capacitance of FO-MO hybrid electrode was initially found to be 65.0 mF cm−2 at 2 mV s−1 and continuously increased to 260.0% after 50 cycles of activation. The capacitance values were considerably comparable or higher than many reported thin-film iron oxide-based anodes in neutral electrolyte. With the protection of MoO2 shell, the FO-MO electrode developed in this study also exhibited excellent cyclic stability (increased to 230.8% after 1000 cycles). This work presents a promising way to improve the electrochemical performance of iron oxide-based anodes for SCs.
Co-reporter:Chong Wang;Lingxia Wu;Hai Wang;Wenhua Zuo;Yuanyuan Li
Advanced Functional Materials 2015 Volume 25( Issue 23) pp:3524-3533
Publication Date(Web):
DOI:10.1002/adfm.201500634
A novel synergistic TiO2-MoO3 (TO-MO) core–shell nanowire array anode has been fabricated via a facile hydrothermal method followed by a subsequent controllable electrodeposition process. The nano-MoO3 shell provides large specific capacity as well as good electrical conductivity for fast charge transfer, while the highly electrochemically stable TiO2 nanowire core (negligible volume change during Li insertion/desertion) remedies the cycling instability of MoO3 shell and its array further provides a 3D scaffold for large amount electrodeposition of MoO3. In combination of the unique electrochemical attributes of nanostructure arrays, the optimized TO-MO hybrid anode (mass ratio: ca. 1:1) simultaneously exhibits high gravimetric capacity (ca. 670 mAh g−1; approaching the hybrid's theoretical value), excellent cyclability (>200 cycles) and good rate capability (up to 2000 mA g−1). The areal capacity is also as high as 3.986 mAh cm−2, comparable to that of typical commercial LIBs. Furthermore, the hybrid anode was assembled for the first time with commercial LiCoO2 cathode into a Li ion full cell, which shows outstanding performance with maximum power density of 1086 W kgtotal −1 (based on the total mass of the TO-MO and LiCoO2) and excellent energy density (285 Wh kgtotal −1) that is higher than many previously reported metal oxide anode-based Li full cells.
Co-reporter:Ruizhi Li;Yimeng Wang;Cheng Zhou;Chong Wang;Xin Ba;Yuanyuan Li;Xintang Huang
Advanced Functional Materials 2015 Volume 25( Issue 33) pp:5384-5394
Publication Date(Web):
DOI:10.1002/adfm.201502265
Iron oxides are promising to be utilized in rechargeable alkaline battery with high capacity upon complete redox reaction (Fe3+ Fe0). However, their practical application has been hampered by the poor structural stability during cycling, presenting a challenge that is particularly huge when binder-free electrode is employed. This paper proposes a “carbon shell-protection” solution and reports on a ferroferric oxide–carbon (Fe3O4–C) binder-free nanorod array anode exhibiting much improved cyclic stability (from only hundreds of times to >5000 times), excellent rate performance, and a high capacity of ≈7776.36 C cm−3 (≈0.4278 C cm−2; 247.5 mAh g−1, 71.4% of the theoretical value) in alkaline electrolyte. Furthermore, by pairing with a capacitive carbon nanotubes (CNTs) film cathode, a unique flexible solid-state rechargeable alkaline battery-supercapacitor hybrid device (≈360 μm thickness) is assembled. It delivers high energy and power densities (1.56 mWh cm−3; 0.48 W cm−3/≈4.8 s charging), surpassing many recently reported flexible supercapacitors. The highest energy density value even approaches that of Li thin-film batteries and is about several times that of the commercial 5.5 V/100 mF supercapacitor. In particular, the hybrid device still maintains good electrochemical attributes in cases of substantially bending, high mechanical pressure, and elevated temperature (up to 80 °C), demonstrating high environmental suitability.
Co-reporter:Dong Wang, Rui Zhang, Jieying Li, Xiaojing Hao, Chunyan Ding, Limin Zhao, Guangwu Wen, Jinping Liu and Weiwei Zhou
Journal of Materials Chemistry A 2017 - vol. 5(Issue 4) pp:NaN1697-1697
Publication Date(Web):2016/12/09
DOI:10.1039/C6TA07936A
Engineering two transition metals into an integrated spinel oxide anode provides great opportunity towards high-performance lithium-ion batteries (LIBs). Spinels with high-valence transition metal oxides (TMOs) however tend to exhibit low initial coulombic efficiency (ICE) due to the irreversible Li2O generated during the first discharge process. Herein, we report a simple and general strategy to synthesize elaborate graphene framework (GF) supported low-valence bicomponent transition metal monoxide anodes (e.g., ZnO–MnO microcubes, ZnO–CoO polyhedra, NiO–CoO nanowires, and (FeO)0.333(MnO)0.667 microspheres, etc.), which can efficiently address the low ICE issue. As a proof of concept demonstration, we show that the ZnO–MnO/GF is indeed more advantageous as an LIB anode over the spinel ZnMn2O4/GF counterpart as well as many other ZnMn2O4-based anodes. Benefiting from the enhanced reversibility of Li+ uptake/extraction and graphene hybridization, the ZnO–MnO/GF electrode exhibits significantly improved ICEs at various current densities, superior rate capability (286 mA h g−1 even at a high current density of 6 A g−1; ∼2.9 min charging/discharging), and extended cycling life (1123 mA h g−1 after 300 cycles) with respect to ZnMn2O4/GF. Such improvements have also been observed for the ZnO–CoO/GF electrode and other analogues. This versatile electrode design could advance our understanding and control of complex TMO-based anodes to gain high ICE and capacity.
