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Nano Research 2018, 11(3): 1415-1425 https://doi.org/10.1007/s12274-017-1757-2
Research Article | Issue | Published: 02 February 2018

Hierarchical Ni-Co-S@Ni-W-O core–shell nanosheet arrays on nickel foam for high-performance asymmetric supercapacitors

Show Author's Information Weidong He1,§,  Zhifu Liang1,§,  Keyu Ji1,  Qingfeng Sun3( ),  Tianyou Zhai2( ),  Xijin Xu1( )
School of Physics and TechnologyUniversity of Jinan336 West Road of Nan XinzhuangJinan250022China
State Key Laboratory of Material Processing and Die & Mould TechnologySchool of Materials Science and EngineeringHuazhong University of Science and Technology (HUST)Wuhan430074China
School of EngineeringZhejiang A & F UniversityHangzhou311300China

§Weidong He and Zhifu Liang contributed equally to this work.

Keywords:
supercapacitors, core/shell structure, free-standing electrode, high energy density, excellent stability
Cite this article:
He W, Liang Z, Ji K, et al. Hierarchical Ni-Co-S@Ni-W-O core–shell nanosheet arrays on nickel foam for high-performance asymmetric supercapacitors. Nano Research, 2018, 11(3): 1415-1425. https://doi.org/10.1007/s12274-017-1757-2
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Abstract Full text Electronic supplementary material About this article

Nickel cobalt sulfides (Ni-Co-S) have attracted extensive attention for application in electronic devices owing to their excellent conductivity and high electrochemical capacitance. To facilitate the large-scale practical application of Ni-Co-S, the excellent rate capability and cyclic stability of these compounds must be fully exploited. Thus, hierarchical Ni-Co-S@Ni-W-O (Ni-Co-S-W) core/shell hybrid nanosheet arrays on nickel foam were designed and synthesized herein via a facile three-step hydrothermal method, followed by annealing in a tubular furnace under argon atmosphere. The hybrid structure was directly assembled as a free-standing electrode, which exhibited a high specific capacitance of 1, 988 F·g-1 at 2 A·g-1 and retained an excellent capacitance of approximately 1, 500 F·g-1 at 30 A·g-1, which is superior to the performance of the pristine Ni-Co-S nanosheet electrode. The assembled asymmetric supercapacitors achieved high specific capacitance (155 F·g-1 at 1 A·g-1), electrochemical stability, and a high energy density of 55.1 W·h·kg-1 at a power density of 799.8 W·kg-1 with the optimized Ni-Co-S-W core/shell nanosheets as the positive electrode, activated carbon as the negative electrode, and 6 M KOH as the electrolyte.


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About this article

Hierarchical Ni-Co-S@Ni-W-O core–shell nanosheet arrays on nickel foam for high-performance asymmetric supercapacitors

Show Author's information Weidong He1,§, Zhifu Liang1,§, Keyu Ji1, Qingfeng Sun3( ), Tianyou Zhai2( ), Xijin Xu1( )
School of Physics and TechnologyUniversity of Jinan336 West Road of Nan XinzhuangJinan250022China
State Key Laboratory of Material Processing and Die & Mould TechnologySchool of Materials Science and EngineeringHuazhong University of Science and Technology (HUST)Wuhan430074China
School of EngineeringZhejiang A & F UniversityHangzhou311300China

§Weidong He and Zhifu Liang contributed equally to this work.

Abstract

Nickel cobalt sulfides (Ni-Co-S) have attracted extensive attention for application in electronic devices owing to their excellent conductivity and high electrochemical capacitance. To facilitate the large-scale practical application of Ni-Co-S, the excellent rate capability and cyclic stability of these compounds must be fully exploited. Thus, hierarchical Ni-Co-S@Ni-W-O (Ni-Co-S-W) core/shell hybrid nanosheet arrays on nickel foam were designed and synthesized herein via a facile three-step hydrothermal method, followed by annealing in a tubular furnace under argon atmosphere. The hybrid structure was directly assembled as a free-standing electrode, which exhibited a high specific capacitance of 1, 988 F·g-1 at 2 A·g-1 and retained an excellent capacitance of approximately 1, 500 F·g-1 at 30 A·g-1, which is superior to the performance of the pristine Ni-Co-S nanosheet electrode. The assembled asymmetric supercapacitors achieved high specific capacitance (155 F·g-1 at 1 A·g-1), electrochemical stability, and a high energy density of 55.1 W·h·kg-1 at a power density of 799.8 W·kg-1 with the optimized Ni-Co-S-W core/shell nanosheets as the positive electrode, activated carbon as the negative electrode, and 6 M KOH as the electrolyte.

Keywords: supercapacitors, core/shell structure, free-standing electrode, high energy density, excellent stability

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Publication history
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Acknowledgements

Publication history

Received: 22 May 2017
Revised: 01 July 2017
Accepted: 04 July 2017
Published: 02 February 2018
Issue date: March 2018

Copyright

© Tsinghua University Press and Springer-Verlag GmbH Germany 2017

Acknowledgements

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 51672109), National Basic Research Program of China (No. 2015CB932600), Program for HUST Interdisciplinary Innovation Team (No. 2015ZDTD038) and the Fundamental Research Funds for the Central University (No. 2017KFKJXX007), Natural Science Foundation of Shandong Province for Excellent Young Scholars (No. ZR2016JL015), Scientific Research Foundation of Zhejiang A & F University (No. 2014FR077).

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