One-pot synthesis of nickel-cobalt hydroxyfluorides nanowires with ultrahigh energy density for an asymmetric supercapacitor

Jian-Fang Zhang; Yan Wang; Xia Shu; Cui-Ping Yu; Ming-Feng Xiao; Jie-Wu Cui; Yong-Qiang Qin; Hong-Mei Zheng; Yong Zhang; Dong Chen; Pulickel M Ajayan; Yu-Cheng Wu

doi:10.1016/j.scib.2018.01.024

One-pot synthesis of nickel-cobalt hydroxyfluorides nanowires with ultrahigh energy density for an asymmetric supercapacitor

Sci Bull (Beijing). 2018 Mar 15;63(5):322-330. doi: 10.1016/j.scib.2018.01.024. Epub 2018 Feb 13.

Authors

Affiliations

¹ School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China.
² School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China; Department of Material Science and Nanoengineering, Rice University, Houston, TX 77005, USA. Electronic address: stone@hfut.edu.cn.
³ School of Instrument Science and Opto-electronics Engineering, Hefei University of Technology, Hefei 230009, China.
⁴ Department of Material Science and Nanoengineering, Rice University, Houston, TX 77005, USA.
⁵ School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China; Key Laboratory of Advanced Functional Materials and Devices of Anhui Province, Hefei 230009, China. Electronic address: ycwu@hfut.edu.cn.

PMID: 36658803
DOI: 10.1016/j.scib.2018.01.024

Abstract

A novel and unique nickel-cobalt hydroxyfluorides (NiCo-HF) nanowires material is fabricated by one-pot solvothermal synthesis method for asymmetric supercapacitor. The synthesis mechanism and factors that influence the formation of the NiCo-HF nanowires have been further discussed. The as-prepared NiCo-HF electrode exhibits a high specific capacitance of 3,372.6 F g^-1, and the capacitance retention of 94.3% can be achieved at a high current density of 20 A g^-1 after 10,000 cycles. The outstanding electrochemical performance of the electrode can be attributed to the synergistic effect of the nanowires morphology and complicated redox process of active material. Furthermore, an asymmetric supercapacitor assembled with NiCo-HF nanowires as positive electrode and activated carbon as the negative electrode shows an ultrahigh energy density of 83.6 Wh kg^-1 at a power density of 379.4 W kg^-1 and an excellent cycling stability with 86.3% capacitance retention after 10,000 cycles, indicating that this novel material has great promise for potential application in energy storage device.

Keywords: Asymmetric supercapacitor; Energy density; Nickel-cobalt hydroxyfluorides; Solvothermal synthesis.