Effects of surface modification on electrochemical performance of MnO2

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.