Formation Mechanisms of Co-Mn Composite Oxide Films from Saturated Solution

Abstract

The formation of Co-Mn composite oxide films on stainless steel electrodes from the dilute aqueous solutions containing Co²⁺ and MnO₄^- ions was studied by the galvanostatic method. It was found that the electrodeposition rates of tha redox reaction products in the solutions were determined by the degree of the supersaturation and the current density. The former had much more influence on the electrodeposition rate than the latter. The degree of the supersaturation depends on the concentration of the reagents and the temperature. The films can be formed from the dilute aqueous solutions at the very low current density and the room temperature.