Electrochemical behaviour of silver in aqueous chromate solutions

The electrochemical behaviour of sliver was studied under cyclic voltammetr y and chronoamperometry conditions in aqueous K2CrO4 solutions. The forward cyclic voltammograms exhibited one oxidation peak, A(1), due to the format ion of Ag2CrO4. The height of the anodic peak, A(1), increases with increas ing chromate concentration, temperature, and scan rate. The solid films for med on the anode surface have been examined by X-ray diffractometry. The re verse voltammograms exhibited two reduction peaks. C-1 and C-2, indicating the formation of two distinct surface layers of Ag2CrO4, an inner compact l ayer reduced in peak C-1 and an oner powdery layer reduced in peak C-2.