High-Power and Ultralong-Life Aqueous Zinc-Ion Hybrid Capacitors Based on Pseudocapacitive Charge Storage

Nano-Micro Letters

Wu Yang¹  Liubing Dong¹  Guoxiu Wang¹  Wang Yang¹  Shuwei Wan²  Fengrong He²  Chengyin Wang³  Yang Li⁴  Feiyu Kang⁵  Chengjun Xu⁵ 

[1] Centre for Clean Energy Technology, Faculty of Science, University of Technology Sydney;HEC Group Pty Ltd;School of Chemistry and Chemical Engineering, Yangzhou University;School of Photovoltaic and Renewable Energy Engineering, University of New South Wales;Shenzhen Geim Graphene Center, Tsinghua Shenzhen International Graduate School, Tsinghua University;

关键词: Zinc-ion hybrid capacitor;    Hydrous ruthenium oxide;    Ultralong life;    Redox pseudocapacitance;    High power;   

DOI  :  10.1007/s40820-019-0328-3

来源: DOAJ

【 摘 要 】

Abstract Rechargeable aqueous zinc-ion hybrid capacitors and zinc-ion batteries are promising safe energy storage systems. In this study, amorphous RuO2·H2O for the first time was employed to achieve fast and ultralong-life Zn2+ storage based on a pseudocapacitive storage mechanism. In the RuO2·H2O||Zn zinc-ion hybrid capacitors with Zn(CF3SO3)2 aqueous electrolyte, the RuO2·H2O cathode can reversibly store Zn2+ in a voltage window of 0.4–1.6 V (vs. Zn/Zn2+), delivering a high discharge capacity of 122 mAh g−1. In particular, the zinc-ion hybrid capacitors can be rapidly charged/discharged within 36 s with a very high power density of 16.74 kW kg−1 and a high energy density of 82 Wh kg−1. Besides, the zinc-ion hybrid capacitors demonstrate an ultralong cycle life (over 10,000 charge/discharge cycles). The kinetic analysis elucidates that the ultrafast Zn2+ storage in the RuO2·H2O cathode originates from redox pseudocapacitive reactions. This work could greatly facilitate the development of high-power and safe electrochemical energy storage.

【 授权许可】

Unknown