无机材料学报

• 研究论文 • 上一篇    下一篇

化学组成对EMD电化学行为的影响

朱立才; 袁中直; 李伟善   

  1. 华南师范大学化学系, 广州 510631
  • 收稿日期:2004-03-01 修回日期:2004-04-15 出版日期:2005-03-20 网络出版日期:2005-03-20

Influence of Composition on the Electrochemical Performance of EMD

ZHU Li-Cai; YUAN Zhong-Zhi; LI Wei-Shan   

  1. Department of Chemistry; South China Normal University; Guangzhou 510631; China
  • Received:2004-03-01 Revised:2004-04-15 Published:2005-03-20 Online:2005-03-20

摘要: 为了了解化学组成对电解二氧化锰(EMD)电化学行为的影响,分析了三种商品 EMD的组成,它们分别为Mn0.8814+Mn0.0443+O1.6552-(OH)0.345-、Mn0.8804+Mn0.0483+O1.6662-(OH)0.334-和 Mn0.8794+Mn0.0543+O1.6772-(OH)0.322-, X射线衍射表明晶型为γ-MnO2.通过循环伏安、恒流放电、 电位-时间关系等实验研究其电化学行为,结果表明,EMD中结合水含量(即阳离子空位数) 增加时,样品开路电压升高、放电容量增大、第1电子还原的峰电位正移.

关键词: 电解二氧化锰, 结合水, 阳离子空位, 电化学行为

Abstract: Three electrolytic manganese dioxide (EMD) samples were characterized by XRD and chemical analyses.
Their electrochemical performances were studied by cyclic voltametry, constant-current discharge, and choronopotentiometry. The results show that the
three samples have the same structure, γ-MnO_2, but their combined water contents are different. The chemical compositions of the three samples
can be formulated as A: Mn4+0.881Mn3+0.044O2-1.655(OH)-0.345, B: Mn4+0.880Mn3+0.048O2-1.666(OH)_0.334 and C:
Mn4+0.879Mn3+0.054O2-1.677(OH)-0.322. The electrochemical performances are influenced by the combined water contents,
which are related to the number of cation-vacancy in the samples. The open circuit potential, the discharge capacity and the peak potential of one
electron reduction increase with the increase of the combined water contents in the samples.

Key words: EMD, combined water, cation-vacancy, electrochemical performance

中图分类号: