Kinetic studies of electrochemical formation of argentous oxide

Abstract

On anodic polarization of silver in alkaline solutions the growth of centres of argentous oxide is controlled by the diffusion/migration of silver ions through a randomly oriented basal layer. In contrast to the kinetics of formation of argentous oxide, the reduction of layers of Ag₂O to silver proceeds via the nucleation and growth of two-dimensional centres in the oxide layer, the electro-chemical step at the surface of the centres being rate determining. The sharp increase in the interfacial resistance at long times in galvanostatic experiments is attributed to the restriction of mass transfer through the layer. Surface reactions and transport through the basal layer are both important in the kinetics of formation of Ag₂O.