The decay of small islands on au signle crystals in contact with sulfuric acid solution under controlled potential

摘要

Surface diffusion of metals in contact with electrolytes closely relates to the reactivity of the atoms on the surfaces and is a key to understand many kinds of electrochemical processes at metal/electrolyte interface, where the electric field is about 10~7 V cm~(-1). We have already reported storng potential dependence of the surface self-diffusion coefficient (_s) on Au(100) and Ag(100) in aqueous 50mM H_2SO_4 solution [1-3]. From the D_2-Erelationship, we propose that the activation energy of surface diffusion decrease becasue of the surface excess charge. In this paper, we investigate the decay of small islands atop on Au signle crystals in sulfuric acid solution under controlled potential at room temperature by in-situ atomic force microscopy [4,5].