Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 15 No. 4 August 2005|
（1. Department of Chemistry, Zhejiang University, Hangzhou 310027, China;
2. State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China）
Abstract: The MnO2 samples coated with Ca(OH)2 were prepared by a liquid-phase surface treatment method. The physical properties of the samples were examined by SEM, EDAX and chemical analysis, and their electrochemical performances were investigated by means of galvanostatic charge-discharge, cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The SEM results show that the samples coated with Ca(OH)2 display a porous surface structure. The electrochemical experiments indicate that the surface modification decreases the polarization of MnO2 electrodes and improves their discharge potentials and discharge capacities.
Key words: manganese dioxide; surface modification; cyclic voltammetry; electrochemical impedance spectroscopy