Nanoscale structural characteristics of photodissolved gold (111) single crystalline surface

The effect of photoillumination on electrochemical reactions of a gold elec trode in KCI electrolyte solution was investigated. The electrode was disso lved by positive polarization in the electrolyte Solution. Anodic current i ncreased when the electrode was illuminated by 830-nm light. Scanning tunne ling microscope images proved that dissolution of the gold electrode was ac celerated by the photoillumination. The surface of the photodissolved elect rode consisted of islands with a flat top and relatively narrow size distri bution. In some cases, uniform structure consisted of small islands was for med by the illumination. The contribution of a highly localized photoexcita tion mode at the surface was discussed to explain the characteristics of th e photoformed surface nanostructure.