期刊
JOURNAL OF POWER SOURCES
卷 186, 期 2, 页码 543-550出版社
ELSEVIER
DOI: 10.1016/j.jpowsour.2008.10.058
关键词
Electrochemical supercapacitors; Manganese oxides; Electrochemical cyclability; Electrochemical impedance spectroscopy; Morphologicaland structural evolution
资金
- Natural Sciences and Engineering Research Council (NSERC) of Canada
- Versa Power Systems (VPS)
The electrochemical cyclability mechanism of nanocrystalline MnO2 electrodes with rock salt-type and hexagonal epsilon-type structures was investigated to determine the relationship between physicochemical feature evolution and the corresponding electrochemical behaviour of MnO2 electrodes. Rock salt MnO2 and hexagonal epsilon-MnO2 electrodes, with fibrous and porous morphologies, evolve into the antifluorite-type MnO2 with a petal-shaped nanosheet structure after electrochemical cycling, similar to that observed in nanocrystalline antifluorite-type MnO2 electrodes after electrochemical cycling. However, a different impedance response was observed for the rock salt MnO2 and hexagonal epsilon-MnO2 electrodes during the charge-discharge cycles, compared with the improved impedance response observed for the cycled antifluorite-type MnO2. A dissolution-redeposition mechanism is proposed to account for the impedance response of the MnO2 electrodes with different morphologies and crystal structures. (c) 2008 Elsevier B.V. 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