Abstract:The polarization behaviors of various oxide electrodes prepared on graphite substrate by thermal decomposition procedure have been investigated by linear sweep voltammetry in chloride melt at 700℃.Experimental results showed that some oxides have obvious electrocatalytic activity for chlorine evolution, lowering anodic overpotential up to 80~110mV at a current density of 0.6A/cm². The kinetic analysis of steady stateJ-Edata in terms of Tafel slopes and chronocoulumetric measuring inferred that the mechanisms of CER on RE oxide electrodes was atom+ion route, with Heyrovsky reaction (Cl_ads+Cl^-→Cl₂+e) being the ratedetermining step, and the adsorption of intermediate species Cladsobeying no-activated Temkin condition.

Key words: chlorine evolution reaction　electrocatalysis　chloride melt　oxide electrode