Co-reporter:Yang Li, Ling-Bin Kong, Mao-Cheng Liu, Wei-Bin Zhang, Long Kang
Materials Letters 2017 Volume 186() pp:289-292
Publication Date(Web):1 January 2017
DOI:10.1016/j.matlet.2016.10.018
•Through a one-step hydrothermal route to prepare the micro/nano flower-like Ni3V2O8.•The pH value of precursor solutions determines the final structure of Ni3V2O8.•The flower-like Ni3V2O8 superstructure shows superior lithium storage properties.•The lithiation-delithiation mechanism of Ni3V2O8 is investigated by ex-situ XRD.A micro/nano flower-like Ni3V2O8 superstructure composed of uniform two-dimensional (2D) nanoplates with thicknesses of 20–50 nm had been successfully synthesized using a facile one-step hydrothermal approach. It was found that the pH value of the mixed precursor solutions played a key role in the formation of flower-like Ni3V2O8 structure. Importantly, the flower-like Ni3V2O8 exhibited a high reversible capacity, good cycling stability (1047.8 mA h g−1 at 200 mA g−1 after 300 cycles), and superior rate capability (640.8 mA h g−1 at 3200 mA g−1) as an anode material for Li-ion batteries. Furthermore, the lithium storage mechanism of Ni3V2O8 involving in a conversion reaction and an intercalation reaction was proposed by ex situ XRD analyses.
Co-reporter:Wei-Bin Zhang;Xue-Jing Ma
Advanced Materials Interfaces 2017 Volume 4(Issue 13) pp:
Publication Date(Web):2017/07/01
DOI:10.1002/admi.201700099
A capacitive electrode material of nanocrystalline intermetallic W2C has been synthesized and studied for electrochemical capacitors. A specific capacitance of 158.2 F g−1 is found in 1 mol dm−3 H2SO4 (aq) at a specific current density of 1 A g−1, and 99.5% of capacitance remains after 5000 cycles of charging–discharging. 88.9% of the initial value remains at a current density of 10 A g−1. W2C exhibits a high electrochemical capacitance that may be attributed to the electrical conductivity, which can promote the electrochemical performance more observably and ensure a long life cycle and fast electrical charge transfer rate. Based on the specific surface areas and specific capacitances, the sub-surface space nonfaradaic pseudocapacitive mechanism is proposed. In addition, the assembled asymmetrical electrochemical capacitor of W2C//activated carbon shows a high energy density and accompanying power density of 19.2 and 8976.6 W kg−1, facilitating high duty applications.
Co-reporter:Zhen-Kun Chen;Jun-Wei Lang;Ling-Yang Liu
RSC Advances (2011-Present) 2017 vol. 7(Issue 32) pp:19967-19975
Publication Date(Web):2017/03/31
DOI:10.1039/C7RA01671A
Lithium-ion hybrid capacitors (LIHCs) have received a mushrooming amount of attention due to their high power density and energy density. However, the imbalanced dynamics between positive and negative electrodes limit their practical applications. Thus, in order to develop a kind of anode material with high power, we report a simple synthesis technology of a NbN nanoparticles/graphene nanosheets (NbN/GNSs) nanocomposite with fast Li insertion/extraction properties. Through a facile solution impregnation followed by annealing treatment, we get a freestanding layer-stacked structure combining 2D graphene nanosheets and 0D NbN nanoparticles. It shows a high reversible capacity of ≈ 450 mA h g−1 at 0.1 A g−1, moreover, as a result of the fast pseudocapacitive performance, it also shows a remarkable rate capability and cycle stability (90% capacity retention at 5 A g−1 after 10 000 cycles). Meanwhile, the LIHC with a NbN/GNSs anode and activated polyaniline derived carbon (APDC) cathode delivers the maximum energy density of 136 W h kg−1, and the highest power density of 25 kW kg−1 as well as a stable cycle life in the potential range of 1.0–4.0 V.
Co-reporter:Bing Hu;Long Kang;Kun Yan;Tong Zhang;Kai Li;Yong-Chun Luo
RSC Advances (2011-Present) 2017 vol. 7(Issue 24) pp:14516-14527
Publication Date(Web):2017/03/03
DOI:10.1039/C7RA01151B
A simple carbonization procedure is proposed for the synthesis of hierarchical nanoporous carbons with controllable pore size and effective surface area as electrode materials for high-performance electrochemical double-layer capacitors. The procedure is based on the carbonization of interpenetrating polymer networks (IPNs) composed of cross-linked polystyrene (PS) and poly(methyl methacrylate) (PMMA). The as-obtained hierarchical nanoporous carbons (HNC-IPNs) have controllable pore size, interconnected pore structure, high specific surface area, excellent electrical conductivity and electrochemical stability with the different mass ratio of PS/PMMA. In addition, there is authentically an excellent linear relationship between effective specific surface area (E-SSA) and specific capacitance. Especially, the HNC-IPN-4 exhibits the highest specific surface area (SSA) of 1346 m2 g−1, relative high E-SSA of 603 m2 g−1, and excellent specific capacitance of 260 F g−1 under the current density of 0.5 A g−1 in 6 M KOH. Meanwhile, the HNC-IPN-4 exhibits a superior cycling performance without any degradation after 10 000 cycles with the current density of 2 A g−1 as well as exhibits high capacitance retention, i.e., 96.0% of the initial specific capacitance after 20 000 cycles.
Co-reporter:Wei-Bin Zhang, Xue-Jing Ma, Adeline Loh, Xiaohong Li, Frank C. Walsh, and Ling-Bin Kong
ACS Energy Letters - New in 2016 2017 Volume 2(Issue 2) pp:
Publication Date(Web):January 9, 2017
DOI:10.1021/acsenergylett.6b00636
LaN is synthesized via calcining La2O3 in NH3 and studied as capacitive material for energy storage. A volumetric capacitance of 951.3 F cm–3 was found in 1 mol dm–3 Na2SO4 using a current density of 1 A g–1, with less than 1% loss of capacitance being experienced after 5000 cycles. In addition, 87.3% of the initial capacitance remained at a current density of 10 A g–1. LaN exhibits high capacitance that is attributed to subsurface space charge accumulation with a possible electric double-layer capacitor component. A reversible electrode process ensures long cycle life and favorable electrical charge transfer. The assembled LaN symmetrical capacitor showed high volumetric energy densities, facilitating high-duty applications.
Co-reporter:Yang Li, Lingbin Kong, Maocheng Liu, Weibin Zhang, Long Kang
Journal of Energy Chemistry 2017 Volume 26, Issue 3(Volume 26, Issue 3) pp:
Publication Date(Web):1 May 2017
DOI:10.1016/j.jechem.2016.11.017
The Co3O4/Co3V2O8/Ni nanocomposites were rationally designed and prepared by a two-step hydrothermal synthesis and subsequent annealing treatment. The one-dimensional (1D) Co3O4 nanowire arrays directly grew on Ni foam, whereas the 1D Co3V2O8 nanowires adhered to parts of Co3O4 nanowires. Most of the hybrid nanowires were inlayed with each other, forming a 3D hybrid nanowires network. As a result, the discharge capacity of Co3O4/Co3V2O8/Ni nanocomposites could reach 1201.8 mAh/g after 100 cycles at 100 mA/g. After 600 cycles at 1 A/g, the discharge capacity was maintained at 828.1 mAh/g. Moreover, even though the charge/discharge rates were increased to 10 A/g, it rendered reversible capacity of 491.2 mAh/g. The superior electrochemical properties of nanocomposites were probably ascribed to their unique 3D architecture and the synergistic effects of two active materials. Therefore, such Co3O4/Co3V2O8/Ni nanocomposites could potentially be used as anode materials for high-performance Li-ion batteries.The three-dimensional Co3O4/Co3V2O8/Ni nanocomposites were rationally designed and fabricated through a stepwise hydrothermal method with subsequent thermal treatment, which exhibited outstanding Li-storage properties, ranking the nanocomposites as promising anode materials for high-performance Li-ion batteries.Download high-res image (203KB)Download full-size image
Co-reporter:Xue-Jing Ma, Wei-Bin Zhang, Ling-Bin Kong, Yong-Chun Luo, Long Kang
Electrochimica Acta 2016 Volume 192() pp:30-37
Publication Date(Web):20 February 2016
DOI:10.1016/j.electacta.2016.01.174
•V6O13, VO2, and V2O3 were gained via a one-step pyrolysis of ammonium metavanadate.•Morphological and mesoporous evolution within the pyrolysis products are investigated.•Electronic conductivity by oxygen vacancy over temperature on capacitance is proposed.•V6O13, VO2, and V2O3 all have a broad potential range and superb capacitance properties.Based on the discussion about the basis of the thermal decomposition of NH4VO3: three pure phase products of V2O3, VO2, V6O13 and their morphological evolution, mesoporous variation, improved electronic conductivity caused by an O vacancy mechanism over temperature, electrochemical measurements show that the V6O13, the VO2, and the V2O3 all exhibit high specific capacitance and energy density, and possess a potential window of −1 V to +1 V in an aqueous solution of Na2SO4.This potential window is similar to that of C materials, which can be used as positive electrodes, also negative. Symmetric electrochemical supercapacitors (ESs) of V2O3//V2O3, VO2//VO2, V6O13//V6O13 and quasi symmetric ESs of V2O3//VO2, VO2//V6O13, V6O13//V2O3 have been assembled, clearly manifest upper energy density and steady cycling charge-discharge ability.
Co-reporter:Xue-Jing Ma, Wei-Bin Zhang, Ling-Bin Kong, Yong-Chun Luo, Long Kang
Electrochimica Acta 2016 Volume 192() pp:45-51
Publication Date(Web):20 February 2016
DOI:10.1016/j.electacta.2016.01.154
•According to electrode potential, negative electrode material β-Bi2O3 is designed.•The electrode exhibits excellent electrochemical energy storage performances.•Based on the morphologies and performances, a possible mechanism is proposed.•The device based on the negative electrode exhibits high energy characteristic.An underlying negative electrode material of β-Bi2O3 has been designed according to the electrode potential, and synthesized via the combination of a similar hydrothermal method and subsequent annealing treatment. The electrochemical evaluation shows that the metastable phase of β-Bi2O3 electrode possessing a wide potential window between −1.5 V to 1.5 V in neutral electrolyte manifests satisfying capacity of 871.2C g−1, superior specific energy of 266 Wh kg−1, outstanding rate capability and excellent cycling stability, which confirms this design and provides a feasible method for later design of negative electrode materials. Based on the morphological characteristics and electrochemical measurements, a possible mechanism is proposed that it'll more conducive to electrochemical behavior for particles owning smooth surface. Also, as an electrochemical application, an electrochemical energy storage device has been assembled, where MnO2 and the β-Bi2O3 acted as the positive and the negative electrodes, respectively, and the specific energy of 32.4 Wh kg−1 is demonstrated at a cell voltage between 0 V to 1.8 V, exhibiting a high energy density and stable power characteristic, which revealed that such a material is promising in electrochemical energy storage applications.
Co-reporter:Xue-Jing Ma, Wei-Bin Zhang, Ling-Bin Kong, Yong-Chun Luo and Long Kang
RSC Advances 2016 vol. 6(Issue 46) pp:40077-40085
Publication Date(Web):11 Apr 2016
DOI:10.1039/C6RA02217K
An underlying electrode material of manganese phosphate has been designed and synthesized, possessing wide potential windows (−0.9–0.7 V in neutral and −0.5–0.6 V in alkaline electrolyte), satisfying specific capacitances (203 F g−1 in neutral and 194 F g−1 in alkaline electrolyte), outstanding rate capabilities and excellent cycling stabilities. The morphological characteristics and electrochemical analyses indicate that the layered crystal structure offers many nano-paths and improves the diffusion of electrolyte ions, which can noticeably promote electrochemical performance. Furthermore, a Mn3(PO4)2//AC asymmetric supercapacitor and a Mn3(PO4)2//Mn3(PO4)2 symmetric supercapacitor have been assembled at a cell voltage between 0 and 1.6 V, and exhibit excellent electrochemical stabilities and stable energy and power characteristics, which reveal that this manganese phosphate material is promising for electrochemical energy storage applications.
Co-reporter:Yang Li, Long Kang, Ling-Bin Kong, Mao-Cheng Liu, Xi-Xin Wang and Wei-Bin Zhang
RSC Advances 2016 vol. 6(Issue 43) pp:36418-36424
Publication Date(Web):05 Apr 2016
DOI:10.1039/C6RA02502A
A new nanostructure of one-dimensional Co3O4/Co3V2O8 hybrid nanowires directly grown on Ti substrates with improved electrochemical Li-storage properties are successfully prepared by a simple hydrothermal strategy. The nanocomposites consist of the primary Co3O4 nanowires acting as the “core” and secondary Co3V2O8 nanocrystals as the “shell” layer, which form one-dimensional tentacle-like nanostructure. When used as potential anodes for lithium ion batteries, the Co3O4/Co3V2O8 hybrid nanowires exhibited an enhanced capacity with high initial discharge capacity of 1677 mA h g−1 at 200 mA g−1 and retained at 1251 mA h g−1 after 200 cycles. Even when the current reached 5000 mA g−1 the electrode can still maintain an average discharge capacity of 807 mA h g−1. The enhanced electrochemical performances are attributed to unique hybrid nanowire architecture and an improved synergistic effect of two electrochemically component, ranking the hybrid nanostructure as a promising electrode material for high-performance energy storage systems.
Co-reporter:Jia-Jia Li, Yu-Xia Hu, Mao-Cheng Liu, Ling-Bin Kong, Yu-Mei Hu, Wei Han, Yong-Chun Luo, Long Kang
Journal of Alloys and Compounds 2016 Volume 656() pp:138-145
Publication Date(Web):25 January 2016
DOI:10.1016/j.jallcom.2015.09.221
•A new method is used to synthesis Ni3S2 nanoparticles electrode for supercapacitors.•The Ni3S2 electrode exhibit excellent electrochemical performances.•AC//Ni3S2 supercapacitor is assembled and the cell delivers long lifespan.Nickel sulfide (Ni3S2) nanoparticles are synthesized via a mechanical alloying method combined with a post heat treatment. The nanoparticles structure of Ni3S2 is characterized by SEM and TEM texts. As electrode material for supercapacitor, the Ni3S2 nanoparticles are characterized by cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) curves, owing to the nanostructure, the Ni3S2 exhibits excellent supercapacitive performance, including high specific capacitance (911 F g−1 at 0.5 A g−1) and remarkable cycling stability. In the end, an asymmetric supercapacitor is fabricated using Ni3S2 as positive electrode and activated carbon (AC) as negative electrode, a maximum specific capacitance of 102 F g−1 is obtained at 0.5 A g−1 and the energy density of 36 Wh kg−1 are demonstrated at a cell voltage between 0 and 1.6 V. These results illustrate that the novel and facile synthetic route may open a new pathway to prepare other alloy compounds with distinctive nanostructure and outstanding electrochemical performance in supercapacitors.Ni3S2 nanoparticles with excellent electrochemical behavior are synthesized as positive materials of supercapacitors via mechanical alloying method combined with a heat treatment, the AC//Ni3S2 exhibited high energy and power density..
Co-reporter:Ming Shi;Jin-Bei Liu;Kun Yan;Jia-Jia Li;Yan-Hua Dai
Ionics 2016 Volume 22( Issue 2) pp:185-192
Publication Date(Web):2016 February
DOI:10.1007/s11581-015-1549-1
The poor electronic conductivity and low lithium-ion diffusion are the two major obstacles to the largely commercial application of LiFePO4 cathode material in power batteries. In order to improve the defects of LiFePO4, a novel carbon source polyacrylonitrile (PAN), which would form the hierarchical porous structure after carbonization, is fabricated and used. This work comes up with a simple and facile carbothermal reduction method to prepare porous-carbon-coated LiFePO4 (C-LiFePO4-PC) composite and to study the effect of carbon-coated temperature on ameliorating the electrochemical performance. The obtained C-LiFePO4-PC composite shows a high initial discharge capacity of 164.1 mA h g−1 at 0.1 C and good cycling stability as well as excellent rate capacity (49.0 mA h g−1 at 50 C). The most possible factors that improve the electrochemical performance could be related to the enhancement of electronic conductivity and the existence of porous carbon layers. In a word, the C-LiFePO4-PC material would become an excellent candidate for application in the fields of lithium-ion batteries.
Co-reporter:Kun Yan, Ling-Bin Kong, Yan-Hua Dai, Ming Shi, Kui-Wen Shen, Bing Hu, Yong-Chun Luo and Long Kang
Journal of Materials Chemistry A 2015 vol. 3(Issue 45) pp:22781-22793
Publication Date(Web):28 Sep 2015
DOI:10.1039/C5TA05947J
Highly structure-controllable mesoporous carbons (HSCMCs) were prepared through a simple carbonization procedure using well-controlled diblock copolymer precursors. We chose polyacrylonitrile-block-polymethylmethacrylate diblock copolymers as precursors, containing a source of carbon, i.e., polyacrylonitrile (PAN), and a sacrificial block, i.e., poly methyl methacrylate (PMMA). PAN-b-PMMA diblock copolymers were synthesized successfully by atom transfer radical polymerization (ATRP) in DMF at 90 °C with well-controlled molecular weight and narrow polydispersity. The as-synthesized PAN-b-PMMA diblock copolymers experienced a microphase-separation process to form a self-assembled nanostructure at 250 °C and then converted to a mesoporous carbon phase after carbonation at 800 °C. The mesoporous sizes of HSCMCs were increased with the increment of molecular weight of the sacrificial block (PMMA). In addition, the HSCMCs exhibited well-controlled mesoporous sizes of 5.96–17.42 nm and high specific surface areas of 427.6–213.1 m2 g−1. The well-controlled pore structure in such materials provided huge potential application as electrode materials for supercapacitors. In particular, HSCMC-5 with an optimal mesoporous size of 13.68 nm could achieve the highest specific capacitance of 254 F g−1 at a current density of 0.5 A g−1 in 2 M KOH aqueous electrolyte. Furthermore, it also possessed an excellent rate capability of 78% capacitance retention as the current density increased from 0.5 A g−1 to 5 A g−1 and a superior cycling performance of 96% capacitance retention after 10000 cycles at a current density of 2 A g−1. Besides, by precisely controlling the pore structure of HSCMCs, the mechanism of electric double layer capacitors could be investigated systematically.
Co-reporter:Wei-Bin Zhang, Ling-Bin Kong, Xue-Jing Ma, Yong-Chun Luo, Long Kang
Journal of Alloys and Compounds 2015 Volume 627() pp:313-319
Publication Date(Web):5 April 2015
DOI:10.1016/j.jallcom.2014.11.192
•NiO–Co3(VO4)2 was fabricated on nickel foam as a binder-free electrode.•NiO–Co3(VO4)2 was synthesized by a simple hydrothermal method.•3D nanostructure has larger surface areas, better permeabilities and more surface active sites.•NiO–Co3(VO4)2 exhibited the satisfactory capacitances and excellent energy densities.•NiO–Co3(VO4)2 displayed desirable stability of 99.4% after 5000 cycles.An advanced binder-free electrode for high-performance supercapacitors has been designed by growing 3D nanostructured NiO–Co3(VO4)2 compound on nickel foam. Such unique nanocomposite combined separately the advantages of the perfect cycling stability and rate capability of Co3(VO4)2 and the high specific capacitances of NiO. Furthermore, the nanostructure of NiO–Co3(VO4)2 could provide higher specific surface area and more active sites. As a result, this electrode exhibited remarkable specific capacitances of 1166 F g−1 at a current density 0.5 A g−1, perfect cycle stability of cycle efficiency 99.4% after 5000 cycles and excellent electrochemical performance than the single oxide electrodes. To enhance energy density, the asymmetric supercapacitor was assembled where NiO–Co3(VO4)2 and activated carbon acted as the positive and negative electrodes, respectively. The maximum specific capacitance of 109 F g−1 and the specific energy of 38.8 W h kg−1 are demonstrated for a cell voltage between 0 and 1.6 V, exhibiting a high energy density and stable power characteristics. And this work also demonstrates the feasibility of rational design of advanced integrated compound electrode for high-performance supercapacitors.
Co-reporter:Jia-Jia Li, Mao-Cheng Liu, Ling-Bin Kong, Dan Wang, Yu-Mei Hu, Wei Han and Long Kang
RSC Advances 2015 vol. 5(Issue 52) pp:41721-41728
Publication Date(Web):24 Apr 2015
DOI:10.1039/C5RA06050H
Ni3(PO4)2@GO composites were fabricated via a facile chemical precipitation method. More importantly, it was observed from electrochemical measurements that the obtained Ni3(PO4)2@GO electrode showed a good specific capacitance (1392.59 F g−1 at 0.5 A g−1) and cycling stability (1302 F g−1 retained after 1000 cycles at 1 A g−1). In addition, a high-voltage asymmetric supercapacitor was successfully fabricated using Ni3(PO4)2@GO and Fe2O3@GO as the positive and negative electrodes, respectively. The asymmetric supercapacitor could be cycled reversibly in the high-voltage region of 0–1.6 V and displayed intriguing performances with a maximum specific capacitance of 189 F g−1 at a current density of 0.25 A g−1. Furthermore, the Fe2O3@GO//Ni3(PO4)2@GO asymmetric supercapacitor exhibited a high energy density of 67.2 W h kg−1 and an excellent long cycle-life along with 88% specific capacitance retention after 1000 cycles. The impressive results presented here may pave the way for promising applications in high energy density storage systems.
Co-reporter:Dan Wang; Ling-Bin Kong;Mao-Cheng Liu; Yong-Chun Luo; Long Kang
Chemistry - A European Journal 2015 Volume 21( Issue 49) pp:17897-17903
Publication Date(Web):
DOI:10.1002/chem.201502269
Abstract
Herein, we describe a simple two-step approach to prepare nickel phosphide with different phases, such as Ni2P and Ni5P4, to explain the influence of material microstructure and electrical conductivity on electrochemical performance. In this approach, we first prepared a Ni–P precursor through a ball milling process, then controlled the synthesis of either Ni2P or Ni5P4 by the annealing method. The as-prepared Ni2P and Ni5P4 are investigated as supercapacitor electrode materials for potential energy storage applications. The Ni2P exhibits a high specific capacitance of 843.25 F g−1, whereas the specific capacitance of Ni5P4 is 801.5 F g−1. Ni2P possesses better cycle stability and rate capability than Ni5P4. In addition, the Fe2O3//Ni2P supercapacitor displays a high energy density of 35.5 Wh kg−1 at a power density of 400 W kg−1 and long cycle stability with a specific capacitance retention rate of 96 % after 1000 cycles, whereas the Fe2O3//Ni5P4 supercapacitor exhibits a high energy density of 29.8 Wh kg−1 at a power density of 400 W kg−1 and a specific capacitance retention rate of 86 % after 1000 cycles.
Co-reporter:Man Xing, Ling-Bin Kong, Mao-Cheng Liu, Ling-Yang Liu, Long Kang and Yong-Chun Luo
Journal of Materials Chemistry A 2014 vol. 2(Issue 43) pp:18435-18443
Publication Date(Web):15 Sep 2014
DOI:10.1039/C4TA03776F
Water splitting, to produce hydrogen and oxygen, has long been considered to be a desirable option for the storage of electrical energy. The catalysts for oxygen evolution reactions (OER) are very important in this process. Herein, we have synthesized Co3V2O8 nanoparticles by a simple and cost-effective technique, which have low crystallinity and large specific surface area (122.8 m2 g−1). Because of the low crystallinity, large specific surface area and suitable pore size, Co3V2O8 nanoparticles yielded an electrocatalytic OER current density of up to 429.7 mA cm−2 at 2.05 V vs. RHE and low OER over potentials of 359 mV (at 10 mA cm−2) and 497 mV (at 100 mA cm−2). In addition, the OER stability of the Co3V2O8 catalyst was very excellent, and the current density at 2.05 V was reduced by just 7.3% after galvanostatic OER measurement at 10 mA cm−2 for 3 h. This work demonstrates that binary metal oxides Co3V2O8 is a highly active and stable oxygen evolution electrocatalyst that can potentially replace expensive noble metal-based anode catalysts for electrochemical water splitting to generate hydrogen fuels.
Co-reporter:Shixiong Sun, Junwei Lang, Rutao Wang, Lingbin Kong, Xiaocheng Li and Xingbin Yan
Journal of Materials Chemistry A 2014 vol. 2(Issue 35) pp:14550-14556
Publication Date(Web):01 Jul 2014
DOI:10.1039/C4TA02026J
Pseudocapacitance is commonly associated with surface or near-surface reversible redox reactions, as observed with transition metal oxides in alkaline aqueous electrolytes. Here, we demonstrate that pseudocapacitive behavior of Fe2O3 can occur in a 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4) ionic liquid (IL), and it is closely related to the chemical state variation between Fe3+ and Fe2+ on the surface of a Fe2O3 electrode during the charging/discharging process. By taking advantage of such pseudocapacitance, we prepared a promising electrode material, i.e., graphene nanosheet-supported Fe2O3 nanoparticles (denoted as Fe2O3@GNS), and then built high-performance asymmetric supercapacitors (ASs) using Fe2O3@GNS as the battery-type electrode material, commercial activated carbon (AC)/or activated polyaniline-derived carbon nanorods (denoted as APDC) as the capacitor-type electrode material, and EMIMBF4 IL as the electrolyte. The as-made ASs are able to work reversibly in a full operation voltage region of 0–4 V and exhibit very high energy density. Especially, the AS of Fe2O3@GNS//APDC achieves an extremely high energy density of 177 W h kg−1 and shows a superior combination of high energy and power density (the energy density still remains 62.4 W h kg−1 even at a high power density of 8 kW kg−1).
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Long Kang, Xiaohong Li, Frank C. Walsh, Man Xing, Chao Lu, Xue-Jing Ma and Yong-Chun Luo
Journal of Materials Chemistry A 2014 vol. 2(Issue 14) pp:4919-4926
Publication Date(Web):12 Feb 2014
DOI:10.1039/C4TA00582A
Binary metal oxides have recently attracted extensive attention from researchers in the energy storage field due to their multiple oxidation states and high energy density. In the present work, Ni3V2O8, Co3V2O8, and the Ni3V2O8/Co3V2O8 nanocomposite are designed and synthesized as a new class of high performance electrode material for supercapacitors. Ni3V2O8 and Co3V2O8 show a structure comprising nanoflakes and nanoparticles, respectively. The Ni3V2O8/Co3V2O8 nanocomposite is prepared by growing Co3V2O8 nanoparticles on the surface of Ni3V2O8 nanoflakes. The composite inherits the structural characteristics and combines the pseudocapacitive benefits of both Ni3V2O8 and Co3V2O8, showing higher specific capacitance than Co3V2O8 and superior rate capability as well as better cycle stability to Ni3V2O8. The dependence of pseudocapacitive properties of the Ni3V2O8/Co3V2O8 nanocomposite on the Ni/Co mass ratio is also investigated, indicating that the high specific capacitance of the composite is contributed by Ni3V2O8, while its excellent rate capability and cycle stability can be attributed to the Co3V2O8 component.
Co-reporter:Jing Du, Ling-Bin Kong, Hong Liu, Jin-Bei Liu, Mao-Cheng Liu, Peng Zhang, Yong-Chun Luo, Long Kang
Electrochimica Acta 2014 Volume 123() pp:1-6
Publication Date(Web):20 March 2014
DOI:10.1016/j.electacta.2013.12.157
•Porous–LiFePO4/C (porous–LFP/C) nanocomposites have been synthesized without templates or surfactants.•The porous–LFP/C performed well even at 30 C (83 mAh g−1) with the 91% of initial capacity after 1000 cycles.•This experimental has the advantage of simple synthesis steps, shorten experimental period, and easy repetition of the process.LiFePO4 electrode material with large specific surface area and porous structure can achieve high energy and power capabilities, but current synthesis method is relatively complicated. Here, we report a facile synthesis of porous–LiFePO4/C (porous–LFP/C) nanocomposites, which require no templates or surfactants. The synthesized porous–LFP/C material possesses outstanding morphology with nano-sized, spherical particles, a desirable core–shell structure with uniform carbon film on the surface of LiFePO4 and with a specific surface area of 29.9 m2 g−1. The as-obtained porous–LFP/C nanocomposites show excellent rate capability and cycling stability. It delivers a discharge capacity of 143 and 126 mAh g−1 at 5 C and 10 C rates, respectively, and exhibits desirable capacity retention after 500 cycles. Remarkably, it performed well even at 30 C (83 mAh g−1) with the 91% of initial capacity after 1000 cycles.
Co-reporter:Ling-Bin Kong, Chao Lu, Mao-Cheng Liu, Yong-Chun Luo, Long Kang, Xiaohong Li, Frank C. Walsh
Electrochimica Acta 2014 Volume 115() pp:22-27
Publication Date(Web):1 January 2014
DOI:10.1016/j.electacta.2013.10.089
In this work, high performance spinel MnCo2O4 electrode was fabricated via a facile sol–gel method and its capacitive behavior was successfully investigated in alkaline electrolyte. MnCo2O4 electrode was characterized by means of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscope (TEM). The pseudo capacitive behavior of spinel MnCo2O4 was widely investigated in 2 M KOH aqueous electrolyte using cyclic voltammetry (CV), galvanostatic charge-discharge test, and electrochemical impedance spectroscopy (EIS). As a result, the spinel MnCo2O4 exhibited excellent porous structure and the highest specific capacitance of 405 F g−1 was achieved at a current density of 5 mA cm−2. In addition, the spinel MnCo2O4 displayed desirable stability in alkaline electrolyte during long-term cycles with a cycling efficiency of 95.1% over 1,000 cycles. The high specific capacitance and excellent cycling ability of MnCo2O4 show promise for its application in supercapacitors.
Co-reporter:Long Kang, Shi-Xiong Sun, Ling-Bin Kong, Jun-Wei Lang, Yong-Chun Luo
Chinese Chemical Letters 2014 Volume 25(Issue 6) pp:957-961
Publication Date(Web):June 2014
DOI:10.1016/j.cclet.2014.05.032
A new application of metal organic framework (MOF) as a pseudo-capacitive material for supercapacitors is investigated. To this end, a simple nickel-based MOF, formulated Ni3(btc)2·12H2O, is synthesized via a hydrothermal reaction. As an electro-active material, such nickel-based MOF exhibits superior pseudo-capacitive behavior in KOH aqueous electrolyte with a high specific capacitance of 726 F g−1. Also, it displays good electrochemical stability with 94.6% of the initial capacitance over consecutive 1000 cycles. In addition, a simple asymmetric supercapacitor with a high energy density of 16.5 Wh kg−1 is successfully built using the nickel-based MOF as positive electrode and commercial activated carbon as negative electrode in KOH electrolyte.We successfully synthesize Ni-based MOFs materials by a simple hydrothermal reaction. As an electro-active material, such nickel-based MOF exhibits superior pseudo-capacitive behavior and good cycling stability in KOH aqueous electrolyte.
Co-reporter:Hong Liu;Peng Zhang;Jing Du;Xiao-Ming Li;Yong-Chun Luo
Ionics 2014 Volume 20( Issue 1) pp:15-21
Publication Date(Web):2014/01/01
DOI:10.1007/s11581-013-0958-2
Submicron rod LiFePO4/C has been synthesized via a facile hydrothermal process. The morphology, crystal structure, and charge–discharge performance of the prepared samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and galvanostatic charge–discharge testing. The SEM and TEM illustrate that submicron rods with a width of about 140 nm and a length of up to 400 nm have been obtained. The TEM test also indicates a “core–shell” structure with a 1.5–2 nm carbon shell on the LiFePO4 core. Even though the separate carbon-coated procedure is not used in this method, the electrochemical behavior results are satisfied. It displays that LiFePO4/C has highly crystalline and a desirable core–shell structure with uniform carbon film. Galvanostatic battery testing shows that LiFePO4/C delivers 104 mAh g−1 at 5 C rates. The highest specific capacity of 166 mAh g−1 is achieved at 0.1 C rate, and 99.8 % of the initial specific capacitance remained after 30 cycles.
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Chao Lu, Xue-Jing Ma, Xiao-Ming Li, Yong-Chun Luo and Long Kang
Journal of Materials Chemistry A 2013 vol. 1(Issue 4) pp:1380-1387
Publication Date(Web):14 Nov 2012
DOI:10.1039/C2TA00163B
CoMoO4–NiMoO4·xH2O bundles with excellent electrochemical behavior were designed and synthesized by a facile strategy. CoMoO4 nanorods were fabricated by a chemical co-precipitation method, and then CoMoO4–NiMoO4·xH2O bundles were prepared by the same method using the CoMoO4 nanorods as the backbone material. A growth mechanism was proposed to explain the formation of the bundles. The composites combine the advantages of the good rate capability of CoMoO4 and the high specific capacitances of NiMoO4·xH2O, showing higher specific capacitances than CoMoO4 and a better rate capability than NiMoO4·xH2O. A maximum specific capacitance of 1039 F g−1 was achieved at a current density of 2.5 mA cm−2, and 72.3% of this value remained at a high current density of 100 mA cm−2. The excellent electrochemical performance makes the composite a promising electrode material for electrochemical capacitors.
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Chao Lu, Xiao-Ming Li, Yong-Chun Luo, Long Kang
Materials Letters 2013 Volume 94() pp:197-200
Publication Date(Web):1 March 2013
DOI:10.1016/j.matlet.2012.12.057
One dimensional CoMoO4 nanorods with monoclinic crystal structure are successfully fabricated by a facile chemical co-precipitation method. The CoMoO4 nanorods synthesized at 70 °C exhibit excellent supercapacitive performance. A high specific capacitance of 286 F g−1 is achieved at a current density of 5 mA cm−2 and 97.5% of the initial specific capacitance is remained after 2000 cycles. The excellent stability is mainly due to the stable crystal structure and good structure stability of one dimension CoMoO4 nanorods. This study puts forward a new research strategy for developing and using of binary metal oxides based new electrode materials in electrochemical capacitors.Highlights► Monoclinic CoMoO4 nanorods were fabricated as a new material for supercapacitors. ► One-dimensional material was fabricated to enhance kinetics of ion transportation. ► CoMoO4 exhibits one-dimensional structure and excellent capacitive behavior. ► It puts forward a new research strategy for binary oxides based materials in ECs.
Co-reporter:Ling-Bin Kong;Rui-Juan Bai;Jun-Wei Lang
Russian Journal of Electrochemistry 2013 Volume 49( Issue 10) pp:975-982
Publication Date(Web):2013 October
DOI:10.1134/S1023193513030087
MnO2 films grown on nickel foam (NF) with a desirable 3D structure are investigated as electrochemical pseudocapacitor materials for potential energy storage applications. The prepared MnO2 films are characterized by X-ray diffraction, FT-IR and scanning electron microscopy. Results indicate that the products are typical hexagonal ɛ-MnO2 with a uniform nanorod structure. The electrochemical measurements showed that the MnO2 films with rods-like morphology have excellent electrochemical performances and its specific capacitance value as single electrode is up to 664 F g−1 at a discharge current density of 5.5 A g−1, which is higher than that of most reported corresponding materials. The specific capacitance retention ratio is 76.7% at the current density range from 5.5 to 30 A g−1. Furthermore, we found that the deposition conditions such as deposition potential and deposition mass have a pronounced effect on their electrochemical activities.
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Chao Lu, Xiao-Ming Li, Yong-Chun Luo, and Long Kang
ACS Applied Materials & Interfaces 2012 Volume 4(Issue 9) pp:4631
Publication Date(Web):August 27, 2012
DOI:10.1021/am301010u
Transition metal oxides possess multiple oxidation states that enable rich redox reactions for pseudo capacitanc. They have been investigated as promising electrode materials to achieve high energy density. In this study, NiO/NiCo2O4/Co3O4 composite with high specific surface and mesoporous structure is fabricated by a sol–gel process then calcined at 250 °C. Benefits from the improved electron conductivity and effective mesoporous structure, the fabricated composite exhibits high specific capacitance (1717 F g–1), enhanced rate capability, and excellent electrochemical stability (94.9% retention after 1000 cycles). Interestingly, the specific capacitance of the composite is higher than that of NiO, NiCo2O4, and Co3O4, which indicates a synergistic effect of the composite on improvement of electrochemical performance. The findings demonstrate the importance and great potential of NiO/NiCo2O4/Co3O4 composite in development of high-performance energy-storage systems.Keywords: capacitive performance; mesoporous composite; mixed metal oxides; supercapacitor;
Co-reporter:Ru-Tao Wang, Ling-Bin Kong, Jun-Wei Lang, Xiao-Wei Wang, Shu-Qiong Fan, Yong-Chun Luo, Long Kang
Journal of Power Sources 2012 Volume 217() pp:358-363
Publication Date(Web):1 November 2012
DOI:10.1016/j.jpowsour.2012.05.115
In this work, amorphous and mesoporous Co3O4 material is obtained from the calcination of loosely packed Co3O4/Co(OH)2 nanosheets which are synthesized by the formation and disassociation of cobalt–citrate complex reaction. We propose that Co nanoparticles are completely oxidized to form the stable cobalt–citrate complex in the presence of sodium citrate and oxygen, and cobalt–citrate complex disassociates to Co(OH)2 under alkaline conditions. The high surface area and mesoporous texture of granular Co3O4 materials are the consequence of the energetically favored topotactic transformation aspect in the solid-state oxidative reaction. Furthermore, mesoporous Co3O4 material exhibits excellent electrochemical capacitance prosperities, well retention to the discharging capacity in cycle lifetime, and a high specific capacitance of 427 F g−1, indicating its potential application in electrochemical capacitors and further in energy and environmental applications.Highlights► The mesoporous Co3O4 materials are synthesized from cobalt-citrate complex. ► The mesoporous Co3O4 materials have a large surface area of 129 m2 g−1. ► The forming mechanism of mesoporous Co3O4 materials has been proposed. ► Mesoporous Co3O4 materials exhibit excellent electrochemical performance.
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Chao Lu, Xiao-Ming Li, Yong-Chun Luo and Long Kang
RSC Advances 2012 vol. 2(Issue 5) pp:1890-1896
Publication Date(Web):06 Jan 2012
DOI:10.1039/C2RA01175A
A surface modified carbon monolith (m-CM) was successfully synthesized by carbonization of a waste paper precursor, followed by a simple surface modification with a HNO3 solution. The morphology, pore structure, and surface functional groups of the as-obtained m-CM are characterized by scanning electron microscopy (SEM), N2 adsorption–desorption measurements, and Fourier transform infrared spectroscopy (FT-IR), respectively. The electrochemical properties are investigated by cyclic voltammetry (CV), galvanostatic charge–discharge, and electrochemical impedance spectroscopy (EIS). After surface modification, the surface hydrophilicity and the electrical conductivity of the m-CM is increased by introducing functional groups and dissolution of the impurities, thus the electrochemical performances of the m-CM are significantly improved. A high gravimetric capacitance (Cm) and volumetric capacitance (Cv) of 232 F g−1 and 36.7 F cm−3 is obtained at a current density of 5 mA cm−2 in 2 M KOH electrolyte, respectively. Based on the above investigation, such a treatment could be a promising method to convert organic waste to high-performance carbon electrode materials for electric double-layer capacitors.
Co-reporter:Fen Ran;Yong-tao Tan;Ji Liu;Lei zhao;Yong-chun Luo;Long Kang
Polymers for Advanced Technologies 2012 Volume 23( Issue 9) pp:1297-1301
Publication Date(Web):
DOI:10.1002/pat.2048
This article reports the preparation and self-assembly of polyaniline (PANI) nanotubes, which were chemically synthesized by using in situ doping polymerization in the presence of ammonium persulfate (APS; (NH4)S2O8) as the oxidant without the use of an external template. The synthesized hierarchically nanotubes with a shape of a single nanotube with a length of 0.6 to 0.8 µm and an average with of 100 nm assembled from nanoparticles. The effects of the [salicylic acid]/[aniline] ratio on the size and capacitance of PANI nanotubes were studied. The specific capacitance behavior of the PANI nanotubes was also investigated by using cyclic voltammogram and galvanostatic charge–discharge tests. A maximum discharge-specific capacitance of 422.5 F/g could be achieved, suggesting its potential application in electrode material for electrochemical capacitors. Copyright © 2011 John Wiley & Sons, Ltd.
Co-reporter:Yong-Tao Tan, Fen Ran, Ling-Bin Kong, Ji Liu, Long Kang
Synthetic Metals 2012 Volume 162(1–2) pp:114-118
Publication Date(Web):February 2012
DOI:10.1016/j.synthmet.2011.11.020
The carbon spheres aggregations (Csa) were synthesized by carbonation of polystyrene spheres aggregations which were prepared by suspension polymerization of styrene. And polyaniline (PANI) was grown on surface of Csa successfully by chemical oxidative polymerization aniline (ANI). Their structures and morphologies were characterized by field emission scanning electron microscopy and Fourier transform infrared spectrometer. Capacitive behaviors were investigated by cyclic voltammetry and galvanostatic charge–discharge. The PANI/m-Csa showed hierarchical structure containing carbon spheres aggregations and PANI nanoparticles. Relationship between the specific capacitance and the composition of m-Csa/PANI composite was also investigated.Highlights► PANI was grown on surface of m-Csa well using chemical oxidative polymerization. ► Processes for preparation of m-Csa/PANI were described and make an explanation. ► A highest capacitance of m-Csa/PANI was 435 F/g.
Co-reporter:Lingbin Kong;Li Deng;Junwei Lang;Xu Ji;Yongchun Luo;Long Kang
Chinese Journal of Chemistry 2012 Volume 30( Issue 3) pp:570-576
Publication Date(Web):
DOI:10.1002/cjoc.201280005
Abstract
Nickel-cobalt oxide nano-flakes materials are successfully synthesized by a facile chemical co-precipitation method followed by a simple calcination process. The studies show that the as-prepared nickel-cobalt oxides with different Ni/Co ratio are composed of NiO and Co3O4 compounds. The Co0.56Ni0.44 oxide material, which exhibits a mesoporous structure with a narrow distribution of pore size from 2 to 7 nm, possesses markedly enhanced charge-discharge properties at high current density compared with the pure NiO and pure Co3O4. The Co0.56Ni0.44 oxide electrode shows a specific capacitance value of 1227 F/g at 5 mA/cm2, which is nearly three times greater than that of the pure NiO electrode at the same current density.
Co-reporter:Ling-Bin Kong, Li Deng, Xiao-Ming Li, Mao-Cheng Liu, Yong-Chun Luo, Long Kang
Materials Research Bulletin 2012 47(7) pp: 1641-1647
Publication Date(Web):
DOI:10.1016/j.materresbull.2012.03.051
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Peng Zhang, Yong-Chun Luo, Long Kang
Electrochimica Acta 2012 60() pp: 443-448
Publication Date(Web):
DOI:10.1016/j.electacta.2011.11.100
Co-reporter:Ling Ren Wang, Fen Ran, Yong Tao Tan, Lei Zhao, Ling Bin Kong, Long Kang
Chinese Chemical Letters 2011 Volume 22(Issue 8) pp:964-968
Publication Date(Web):August 2011
DOI:10.1016/j.cclet.2011.01.019
Coral reef-like PANI nanotubes composed of nanopaticles were successfully synthesized by a reactive template of manganese oxide. The structure was characterized by using SEM, TEM, and FT-IR, and the supercapacitive behaviors of these nanotubes were investigated with cyclic voltammetry (CV), and charge–discharge tests, respectively. A maximum specific capacitance of 533 F/g could be achieved in 1 mol/L aqueous H2SO4 with the potential range of −0.2 to 0.8 V (vs. the saturated calomel electrode) in a half-cell setup configuration for PANI electrode, suggesting its potential application in the electrode material for electrochemical capacitors.
Co-reporter:Ling-Bin Kong;Mao-Cheng Liu;Jun-Wei Lang
Journal of Solid State Electrochemistry 2011 Volume 15( Issue 3) pp:571-577
Publication Date(Web):2011 March
DOI:10.1007/s10008-010-1125-6
A new porous cobalt hydroxide film has been successfully electrodeposited on nickel foam from 0.1 M cobalt nitrate electrolyte at −1.0 V vs. SCE without adding any surfactant. The microstructure and surface morphology of prepared cobalt hydroxide films were physically characterized by X-ray diffraction analysis and scanning electron microscopy. The results indicate that an interlaced network structure was obtained. The effects of electrodeposition time, deposition potential, and different substrates on the specific capacitance and microstructure of prepared porous α-Co(OH)2 thin film were systematically studied. The results indicate that the film deposited on nickel foam at −1.0 V has excellent electrochemical properties. A maximum specific capacitance of 1473 F g−1 could be achieved at a current density of 2 A g−1.
Co-reporter:Jing Zhang, Ling-Bin Kong, Jian-Jun Cai, Yong-Chun Luo, Long Kang
Electrochimica Acta 2010 Volume 55(Issue 27) pp:8067-8073
Publication Date(Web):30 November 2010
DOI:10.1016/j.electacta.2010.01.052
Nano-thin polypyrrole (PPy) layers were coated on chemically modified ordered mesoporous carbon (m-CMK-3) by an in situ chemical polymerization. Structural and morphological characterizations of m-CMK-3/PPy composites were carried out using field emission scanning electron microscopy. Pseudo-capacitive behavior of the deposited PPy layers on m-CMK-3 was investigated by cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy. As results of this study, the thin layer of PPy in the composite electrode was effective to obtain fully reversible and very fast Faradaic reaction. A maximum discharge capacity of 427 F g−1 or 487 F g−1 after correcting for weight percent of PPy phase at the current density of 5 mA cm−2, could be achieved in a half-cell setup configuration for the m-CMK-3/PPy composites electrode, suggesting its potential application in electrode material for electrochemical capacitors.
Co-reporter:Jing Zhang, Ling-Bin Kong, Jian-Jun Cai, Heng Li, Yong-Chun Luo, Long Kang
Microporous and Mesoporous Materials 2010 Volume 132(1–2) pp:154-162
Publication Date(Web):July 2010
DOI:10.1016/j.micromeso.2010.02.013
Hierarchically porous composite materials consisting of nanoflake-like nickel hydroxide and mesoporous carbon are synthesized by a facile chemical precipitation method. The effects of microstructure and morphology of the carbon support on the electrochemical properties of the composite are also investigated. Structural characterizations have revealed that nanometer-sized nickel hydroxide nanoflakes can grow on the surface of mesoporous carbon supports. The mesoporous carbon-based composites shows better structure with interlaced nanoflakes and higher specific capacitance than activated carbon-based composite. The composite material with mesoporous carbon morphology of large particle size and long channel lengths possesses the highest specific capacitance of 2570 F/g, suggesting its potential applications as the electrode materials for electrochemical capacitors. The overall improved electrochemical behavior can be attributed to the unique structure design in nickel hydroxide/mesoporous carbon composite in terms of its nanostructure, large specific surface area and good electrical conductance.
Co-reporter:Ling-Bin Kong, Heng Li, Jing Zhang, Yong-Chun Luo, Long Kang
Applied Surface Science 2010 Volume 256(Issue 22) pp:6688-6693
Publication Date(Web):1 September 2010
DOI:10.1016/j.apsusc.2010.04.071
Abstract
Ordered mesoporous carbons CMK-3 with various morphologies are synthesized by using various mesoporous silica SBA-15 as template and then support to prepare Pt/CMK-3 catalyst. The obtained catalysts are compared in terms of the electrocatalytic activity for methanol oxidation in sulfuric acidic solutions. The structure characterizations and electrochemical analysis reveal that Pt catalysts with the CMK-3 support of large particle size and long channel lengths possess larger electrochemical active surface area (ECSA) and higher activity toward methanol oxidation than those with the other two supports. The better performance of Pt/CMK-3 catalyst may be due to the larger area of electrode/electrolyte interface and larger ECSA value of Pt catalyst, which will provide better structure in favor of the mass transport and the electron transport.
Co-reporter:Jian Jun Cai, Ling Bin Kong, Jing Zhang, Yong Chun Luo, Long Kang
Chinese Chemical Letters 2010 Volume 21(Issue 12) pp:1509-1512
Publication Date(Web):December 2010
DOI:10.1016/j.cclet.2010.07.003
A novel nano-composite of polyaniline/mesoporous carbon (PANI/CMK-3) was prepared with mesoporous carbon (CMK-3) serving as the support. Electrochemical asymmetric capacitors have been successfully designed by using PANI/CMK-3 composite and CMK-3 as positive and negative electrode, respectively. The results showed that the discharge capacity of the asymmetric capacitor could reach 87.4 F/g under the current density of 5 mA/cm2 and cell voltage of 1.4 V. The energy density of the asymmetric capacitor was up to 23.8 Wh/kg with a power density of 206 W/kg. Furthermore, PANI/CMK-3–CMK-3 asymmetric capacitor using this PANI/CMK-3 nano-composite could be activated quickly and possess high charge–discharge efficiency.
Co-reporter:Long Kang, Ru-Tao Wang, Ling-Bin Kong, Heng Li, Jing Zhang, Yong-Chun Luo
Materials Letters 2010 Volume 64(Issue 19) pp:2064-2067
Publication Date(Web):15 October 2010
DOI:10.1016/j.matlet.2010.06.040
Ni nanoparticles have been fabricated on the surface of CMK-3 mesoporous carbon through an immersion-electrodeposition (IE) technique. Transmission electron microscopy analysis indicated that it was a facile approach to electrochemically prepare nano-sized Ni clusters. The electrocatalytic properties of Ni/CMK-3 nanocomposites electrode for hydrogen evolution reaction have been investigated by liner scanning voltammetry in alkaline solution, and high electrocatalytic activity was observed. Therefore, for the first time, we report this IE method as a new route to prepare metal/CMK-3 nanocomposites which have potential applications in the catalytic field.
Co-reporter:Ling-Bin Kong, Jian-Jun Cai, Lin-Lin Sun, Jing Zhang, Yong-Chun Luo, Long Kang
Materials Chemistry and Physics 2010 Volume 122(2–3) pp:368-373
Publication Date(Web):1 August 2010
DOI:10.1016/j.matchemphys.2010.03.007
A nano-flake network cobalt hydroxide and well-ordered hexagonal mesoporous silica SBA-15 molecular sieves nanocomposite materials (designated as Co(OH)2/SBA-15) for electrochemical capacitor electrode have been prepared using a liquid-precipitated method. The electrochemical capacitance characterization of the Co(OH)2/SBA-15 materials was performed using cyclic voltammetry, chronopotentiometry, and impedance spectroscopy, respectively. These nano-flakes cobalt hydroxide maintain high utilization at high rates of discharge. A maximum specific capacitance of 467.5 F g−1 can be achieved in 2 M aqueous KOH with the potential range from −0.2 to 0.4 V (vs. SCE) in a three-electrode glass cell at room temperature for the Co(OH)2/SBA-15 electrode, suggesting its potential application in electrochemical capacitors. Furthermore, the effect of annealing temperatures on the electrochemical capacitance characteristics has also been explored.
Co-reporter:Jing Zhang;Jian-Jun Cai
Journal of Solid State Electrochemistry 2010 Volume 14( Issue 11) pp:2065-2075
Publication Date(Web):2010 November
DOI:10.1007/s10008-010-1035-7
Nanocomposites consisting of mesoporous carbon CMK-3 and cobalt hydroxide nanoflakes are synthesized by a chemical precipitation method. The successful growth of nanometer-sized Co(OH)2 flakes on the surface of CMK-3 is confirmed by scanning electron microscopy. The Co(OH)2/CMK-3 composite electrodes are investigated for its use in the electrochemical capacitors with cyclic voltammograms, chronopotentiometric measurements, and electrochemical impedance spectroscopy. Experimental studies reveal that the Co(OH)2/CMK-3 composite electrode with the 20 wt.% CMK-3 presents excellent electrochemical performance with specific capacitance of 750 F/g (or 910 F/g after being corrected for the weight percentage of the Co(OH)2 phase). The overall improved electrochemical behavior accounts for the unique structure design in the Co(OH)2/CMK-3 composite in terms of porous nanostructure, large specific surface area, and good electrical conductance. The Co(OH)2/CMK-3 composite electrode also shows better rate capability and cyclic stability, suggesting its potential applications as the electrode materials for electrochemical capacitors.
Co-reporter:Ling-Bin Kong, Jun-Wei Lang, Min Liu, Yong-Chun Luo, Long Kang
Journal of Power Sources 2009 Volume 194(Issue 2) pp:1194-1201
Publication Date(Web):1 December 2009
DOI:10.1016/j.jpowsour.2009.06.016
Cobalt hydroxide nano-flakes are successfully synthesized by a facile chemical precipitation method. Electrochemical characterization is performed using cyclic voltammetry, chronopotentiometry and impedance spectroscopy, respectively. These cobalt hydroxide nano-flakes maintain high utilization at high rates of discharge. A maximum specific capacitance of 735 F g−1 can be achieved in 2 M aqueous KOH with the potential range from −0.2 to 0.4 V (vs. SCE) in a half-cell setup configuration for the nano-flakes Co(OH)2 electrode, suggesting its potential application in electrochemical capacitors. Furthermore, the effect of annealing temperatures on the electrochemical capacitance characteristics is also been systematically explored.
Co-reporter:Jing Zhang, Ling-Bin Kong, Bin Wang, Yong-Chun Luo, Long Kang
Synthetic Metals 2009 Volume 159(3–4) pp:260-266
Publication Date(Web):February 2009
DOI:10.1016/j.synthmet.2008.09.018
Multi-walled carbon nanotube (MWCNT)/polyaniline (PANI) composite films were prepared by in-situ electrochemical polymerization of an aniline solution containing different MWCNT contents. The supercapacitive behaviors of these films were investigated with cyclic voltammetry (CV), charge–discharge tests, and ac impedance spectroscopy. The results revealed that the MWCNT/PANI films show much higher specific capacitance (SC), better power characteristic, better cyclic stability, and more promising for applications in supercapacitors than a pure PANI film electrode. The highest specific capacitance value of 500 F g−1 was obtained for the MWCNT/PANI composite film containing MWCNT of 0.8 wt.%. The improvement mechanisms of the capacitance of the composites are also discussed in detail.
Co-reporter:Jun-Wei Lang;Wei-Jin Wu;Min Liu
Journal of Solid State Electrochemistry 2009 Volume 13( Issue 2) pp:
Publication Date(Web):2009 February
DOI:10.1007/s10008-008-0560-0
Loose-packed nickel hydroxides were successfully synthesized by a facile chemical precipitation method. Structure characterizations indicate that a nanoflake structure with low crystallinity for the nickel hydroxide samples was obtained. Electrochemical studies were carried out using cyclic voltammetry, chronopotentiometry technology, and alternating current impedance spectroscopy, respectively. A maximum specific capacitance of 2,055F/g could be achieved in 2M aqueous KOH with the potential range of 0 to 0.4V (vs. the saturated calomel electrode) in a half-cell setup configuration for the nanoflake Ni(OH)2 electrode, suggesting its potential application in the electrode material for electrochemical capacitors. Furthermore, the effect of annealing temperatures on the electrochemical capacitance characteristics has also been systemically explored.
Co-reporter:Jun-Wei Lang, Ling-Bin Kong, Wei-Jin Wu, Yong-Chun Luo and Long Kang
Chemical Communications 2008 (Issue 35) pp:4213-4215
Publication Date(Web):15 Jul 2008
DOI:10.1039/B800264A
The nickel oxide nano-flakes materials prepared by a facile approach maintain high power density at high rates of discharge and have excellent cycle life, suggesting their potential application in supercapacitors.
Co-reporter:Ling-Bin Kong, Yi Huang, Yi Guo, Hu-Lin Li
Materials Letters 2005 Volume 59(Issue 13) pp:1656-1659
Publication Date(Web):June 2005
DOI:10.1016/j.matlet.2005.01.036
Ordered nanostripe structures on aluminum surface were obtained by electropolishing unannealed polycrystalline aluminum sheet in the C2H5OH and HClO4 solution [V(C2H5OH)/V(HClO4)=4:1] at room temperature for 10 s, with the cell voltage at 20 V.
Co-reporter:Yang Li, Ling-Bin Kong, Mao-Cheng Liu, Wei-Bin Zhang, Long Kang
Ceramics International (January 2017) Volume 43(Issue 1) pp:
Publication Date(Web):1 January 2017
DOI:10.1016/j.ceramint.2016.10.058
The Co3V2O8 nanoparticle arrays on Ni foam were synthesized by a simple one-step procedure using a low-temperature hydrothermal method. This architecture consisted of ultrafine Co3V2O8 nanoparticles with a mean size of 30–60 nm, which covered homogeneously onto the porous Ni foam, forming a uniform film-like morphology. The Co3V2O8 nanoparticles not only provided sufficient electro-active interactions for Li-storages reaction, but also had good mechanical contact with the Ni foam, hence improving reaction kinetics and enhancing electrode integrity. When used as a new sort of binder-free anode for Li-ion batteries (LIBs), this unique electrode delivered high initial discharge capacity of 1586.9 mA h g−1 at 200 mA g−1 and retained at 1289 mA h g−1 after 100 cycles, and the discharge capacity maintained at 1004.4 mA h g−1 after 800 cycles at 500 mA g−1. Even when the current was 10 A g−1, discharge capacity of 471.4 mA h g−1 could be achieved. In addition, the charge/discharge mechanism of Co3V2O8 based on conversion and intercalation reaction routes were verified by ex-situ XRD diffraction. Therefore, the Co3V2O8 nanoparticle arrays on Ni foam might open a new insight for transition metal oxides as electrode materials for LIBs.
Co-reporter:Ling-Yang Liu, Xu Zhang, Hong-Xia Li, Bao Liu, Jun-Wei Lang, Ling-Bin Kong, Xing-Bin Yan
Chinese Chemical Letters (February 2017) Volume 28(Issue 2) pp:
Publication Date(Web):February 2017
DOI:10.1016/j.cclet.2016.07.027
Li-ion hybrid capacitors (LIHCs), composing of a lithium-ion battery (LIB) type anode and a supercapacitor (SC) type cathode, gained worldwide popularity due to harmonious integrating the virtues of high energy density of LIBs with high power density of SCs. Herein, nanoflakes composed microflower-like Co–Ni oxide (CoNiO) was successfully synthesized by a simple co-precipitation method. The atomic ratio of as-synthesized CoNiO is determined to be 1:3 through XRD and XPS analytical method. As a typical battery-type material, CoNiO and capacitor-type activated polyaniline-derived carbon (APDC) were used to assemble LIHCs as the anode and cathode materials, respectively. As a result, when an optimized mass ratio of CoNiO and APDC was 1:2, CoNiO//APDC LIHC could deliver a maximum energy density of 143 Wh kg−1 at a working voltage of 1–4 V. It is worth mentioning that the LIHC also exhibits excellent cycle stability with the capacitance retention of ∼78.2% after 15,000 cycles at a current density of 0.5 A g−1.As a typical battery-type material, Co–Ni oxide (CoNiO) which was synthesized by a simple co-precipitation method and capacitor-type activated polyaniline-derived carbon (APDC) were used to assemble LIHCs as the anode and cathode electrode materials, respectively. The assembled LIHC exhibits excellent cycle stability with the capacitance retention of ∼78.2% after 15,000 cycles at a current density of 0.5 A g−1.
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Chao Lu, Xue-Jing Ma, Xiao-Ming Li, Yong-Chun Luo and Long Kang
Journal of Materials Chemistry A 2013 - vol. 1(Issue 4) pp:NaN1387-1387
Publication Date(Web):2012/11/14
DOI:10.1039/C2TA00163B
CoMoO4–NiMoO4·xH2O bundles with excellent electrochemical behavior were designed and synthesized by a facile strategy. CoMoO4 nanorods were fabricated by a chemical co-precipitation method, and then CoMoO4–NiMoO4·xH2O bundles were prepared by the same method using the CoMoO4 nanorods as the backbone material. A growth mechanism was proposed to explain the formation of the bundles. The composites combine the advantages of the good rate capability of CoMoO4 and the high specific capacitances of NiMoO4·xH2O, showing higher specific capacitances than CoMoO4 and a better rate capability than NiMoO4·xH2O. A maximum specific capacitance of 1039 F g−1 was achieved at a current density of 2.5 mA cm−2, and 72.3% of this value remained at a high current density of 100 mA cm−2. The excellent electrochemical performance makes the composite a promising electrode material for electrochemical capacitors.
Co-reporter:Man Xing, Ling-Bin Kong, Mao-Cheng Liu, Ling-Yang Liu, Long Kang and Yong-Chun Luo
Journal of Materials Chemistry A 2014 - vol. 2(Issue 43) pp:NaN18443-18443
Publication Date(Web):2014/09/15
DOI:10.1039/C4TA03776F
Water splitting, to produce hydrogen and oxygen, has long been considered to be a desirable option for the storage of electrical energy. The catalysts for oxygen evolution reactions (OER) are very important in this process. Herein, we have synthesized Co3V2O8 nanoparticles by a simple and cost-effective technique, which have low crystallinity and large specific surface area (122.8 m2 g−1). Because of the low crystallinity, large specific surface area and suitable pore size, Co3V2O8 nanoparticles yielded an electrocatalytic OER current density of up to 429.7 mA cm−2 at 2.05 V vs. RHE and low OER over potentials of 359 mV (at 10 mA cm−2) and 497 mV (at 100 mA cm−2). In addition, the OER stability of the Co3V2O8 catalyst was very excellent, and the current density at 2.05 V was reduced by just 7.3% after galvanostatic OER measurement at 10 mA cm−2 for 3 h. This work demonstrates that binary metal oxides Co3V2O8 is a highly active and stable oxygen evolution electrocatalyst that can potentially replace expensive noble metal-based anode catalysts for electrochemical water splitting to generate hydrogen fuels.
Co-reporter:Shixiong Sun, Junwei Lang, Rutao Wang, Lingbin Kong, Xiaocheng Li and Xingbin Yan
Journal of Materials Chemistry A 2014 - vol. 2(Issue 35) pp:NaN14556-14556
Publication Date(Web):2014/07/01
DOI:10.1039/C4TA02026J
Pseudocapacitance is commonly associated with surface or near-surface reversible redox reactions, as observed with transition metal oxides in alkaline aqueous electrolytes. Here, we demonstrate that pseudocapacitive behavior of Fe2O3 can occur in a 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4) ionic liquid (IL), and it is closely related to the chemical state variation between Fe3+ and Fe2+ on the surface of a Fe2O3 electrode during the charging/discharging process. By taking advantage of such pseudocapacitance, we prepared a promising electrode material, i.e., graphene nanosheet-supported Fe2O3 nanoparticles (denoted as Fe2O3@GNS), and then built high-performance asymmetric supercapacitors (ASs) using Fe2O3@GNS as the battery-type electrode material, commercial activated carbon (AC)/or activated polyaniline-derived carbon nanorods (denoted as APDC) as the capacitor-type electrode material, and EMIMBF4 IL as the electrolyte. The as-made ASs are able to work reversibly in a full operation voltage region of 0–4 V and exhibit very high energy density. Especially, the AS of Fe2O3@GNS//APDC achieves an extremely high energy density of 177 W h kg−1 and shows a superior combination of high energy and power density (the energy density still remains 62.4 W h kg−1 even at a high power density of 8 kW kg−1).
Co-reporter:Mao-Cheng Liu, Ling-Bin Kong, Long Kang, Xiaohong Li, Frank C. Walsh, Man Xing, Chao Lu, Xue-Jing Ma and Yong-Chun Luo
Journal of Materials Chemistry A 2014 - vol. 2(Issue 14) pp:NaN4926-4926
Publication Date(Web):2014/02/12
DOI:10.1039/C4TA00582A
Binary metal oxides have recently attracted extensive attention from researchers in the energy storage field due to their multiple oxidation states and high energy density. In the present work, Ni3V2O8, Co3V2O8, and the Ni3V2O8/Co3V2O8 nanocomposite are designed and synthesized as a new class of high performance electrode material for supercapacitors. Ni3V2O8 and Co3V2O8 show a structure comprising nanoflakes and nanoparticles, respectively. The Ni3V2O8/Co3V2O8 nanocomposite is prepared by growing Co3V2O8 nanoparticles on the surface of Ni3V2O8 nanoflakes. The composite inherits the structural characteristics and combines the pseudocapacitive benefits of both Ni3V2O8 and Co3V2O8, showing higher specific capacitance than Co3V2O8 and superior rate capability as well as better cycle stability to Ni3V2O8. The dependence of pseudocapacitive properties of the Ni3V2O8/Co3V2O8 nanocomposite on the Ni/Co mass ratio is also investigated, indicating that the high specific capacitance of the composite is contributed by Ni3V2O8, while its excellent rate capability and cycle stability can be attributed to the Co3V2O8 component.
Co-reporter:Jun-Wei Lang, Ling-Bin Kong, Wei-Jin Wu, Yong-Chun Luo and Long Kang
Chemical Communications 2008(Issue 35) pp:NaN4215-4215
Publication Date(Web):2008/07/15
DOI:10.1039/B800264A
The nickel oxide nano-flakes materials prepared by a facile approach maintain high power density at high rates of discharge and have excellent cycle life, suggesting their potential application in supercapacitors.
Co-reporter:Kun Yan, Ling-Bin Kong, Yan-Hua Dai, Ming Shi, Kui-Wen Shen, Bing Hu, Yong-Chun Luo and Long Kang
Journal of Materials Chemistry A 2015 - vol. 3(Issue 45) pp:NaN22793-22793
Publication Date(Web):2015/09/28
DOI:10.1039/C5TA05947J
Highly structure-controllable mesoporous carbons (HSCMCs) were prepared through a simple carbonization procedure using well-controlled diblock copolymer precursors. We chose polyacrylonitrile-block-polymethylmethacrylate diblock copolymers as precursors, containing a source of carbon, i.e., polyacrylonitrile (PAN), and a sacrificial block, i.e., poly methyl methacrylate (PMMA). PAN-b-PMMA diblock copolymers were synthesized successfully by atom transfer radical polymerization (ATRP) in DMF at 90 °C with well-controlled molecular weight and narrow polydispersity. The as-synthesized PAN-b-PMMA diblock copolymers experienced a microphase-separation process to form a self-assembled nanostructure at 250 °C and then converted to a mesoporous carbon phase after carbonation at 800 °C. The mesoporous sizes of HSCMCs were increased with the increment of molecular weight of the sacrificial block (PMMA). In addition, the HSCMCs exhibited well-controlled mesoporous sizes of 5.96–17.42 nm and high specific surface areas of 427.6–213.1 m2 g−1. The well-controlled pore structure in such materials provided huge potential application as electrode materials for supercapacitors. In particular, HSCMC-5 with an optimal mesoporous size of 13.68 nm could achieve the highest specific capacitance of 254 F g−1 at a current density of 0.5 A g−1 in 2 M KOH aqueous electrolyte. Furthermore, it also possessed an excellent rate capability of 78% capacitance retention as the current density increased from 0.5 A g−1 to 5 A g−1 and a superior cycling performance of 96% capacitance retention after 10000 cycles at a current density of 2 A g−1. Besides, by precisely controlling the pore structure of HSCMCs, the mechanism of electric double layer capacitors could be investigated systematically.
