Abstract
Surface treatment methods by use of charge discharge cycling, KBH 4 reduction and KOH etching were parallely investigated for the rapid activation of Mn(NiCoMnAl) 5 electrode. It is found that the MH electrode treated with hot and concentrated KOH solution exhibits rapid and full activation, and also gives lower discharge overvoltage, higher stable capacity and improved cycleability. It is also revealed from SEM, EDAX and ICP analysis that the KOH activation of the electrode proceeds mainly through the enrichment of mischmetal and nickel in surface to form electrocatalytically active surface for hydrogen absorption reaction, but the surface modification with KBH 4 or electrochemical treatment takes place by the pulverization of the MH alloy particles by the hydrogenation reaction to create large amount highly reactive new surface and crystal defects.
Keywords
Hydrogen storage electrode, Activation, Surface mod
Publication Date
1996-05-28
Online Available Date
1996-05-28
Revised Date
1996-05-28
Received Date
1996-05-28
Recommended Citation
Ronghui Hu, Hanxi Yang, Shigang Lu, Shengxian Li, Jingcheng Liu, Chongzhi Yang.
Studies of Surface Treatment Methods and Their Operating Mechanisms for Activation of Hydrogen Storage Electrode[J]. Journal of Electrochemistry,
1996
,
2(2): Article 10.
DOI: 10.61558/2993-074X.3070
Available at:
https://jelectrochem.xmu.edu.cn/journal/vol2/iss2/10
References
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