期刊
ELECTROCHIMICA ACTA
卷 397, 期 -, 页码 -出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.electacta.2021.139255
关键词
Zn2+ ion batteries; V2O5; Cathode materials; Zn(2+)storage performance; Structure evolution
资金
- National Natural Science Foundation of China [51664012, 22065010]
- Guangxi Natural Science Foundation of China [2015GXNSFGA139006]
Understanding the relationship between electrochemical performance and microstructural variation of electrodes is essential for developing high-performance electrode materials. The orthorhombic V2O5 nanowires as a cathode material for Zn-ion batteries demonstrated a reversible capacity of 276 mA h g(-1) and structural evolution during cycling, with morphology changing from nanowires to nanofibers. The cycling performance curve showed three distinct regions: initial capacity increase, fast capacity decay, and relatively stable capacity regions.
A fundamental understanding of the relationship between electrochemical performance and microstruc-tural variation of electrodes is crucial for developing high-performance electrode materials. In this work, the Zn2+ storage performance and structural evaluation of orthorhombic V2O5 nanowires as a cathode material for Zn-ion batteries in ZnSO4 electrolyte were investigated. At 10 0 0 mA g(-1), the orthorhom-bic V2O5 nanowires exhibited a maximum reversible capacity of 276 mA h g(-1) and retained a capacity of 152/95 mA h g(-1) after 50 0/20 0 0 cycles. The cycling performance curve shows three distinct regions: initial capacity increase region (stage I), fast capacity decay region (stage II), and relatively stable capac-ity region (stage III). The structural evolution of the orthorhombic V2O5 nanowires during cycling was analyzed by ex-situ SEM and XRD characterizations. It demonstrated that upon repeated cycling the or-thorhombic V2O5 nanowires experience morphology changes from nanowires to nanofibers and finally interweaved nanofibers; meanwhile, the phase structure transforms from orthorhombic to amorphous phase and accompanied with the formation of Zn-3(OH)(2)V2O7 center dot 2H(2)O phase, which accounts for the capacity change of the electrode during long-term cycling. The pseudocapacitive behavior and Zn2+ diffusion coefficient during discharge/charge processes were analyzed by the sweep voltammetry method and galvanostatic intermittent titration technique, respectively. (C) 2021 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据