Electrocatalysis of Anodic Oxygen‐Transfer Reactions: Ultrathin Films of Lead Oxide on Solid Electrodes

Ultrathin films of lead oxide, concluded to be , were generated on the surfaces of Au, Pt, Ti, and GC electrodes during rapid voltammetric dissolution of thick films (> ca. 10–100 μm) of deposited from acidic solutions containing Pb 2+ . These films were stable at potential values > ca. 0.5V negative of the peak potential for cathodic stripping of bulk . Ultrathin films of were produced, in turn, by anodization of the films in Pb 2+ ‐free solutions. Results are emphasized here for the voltammetric and microscopic characterization of these thin films at Au electrodes. The formation of the stable film during cathodic dissolution of thick films is concluded to be the result of a deficiency of H + in the interfacial region between the substrates and the porous thick oxide films. Ultrathin films were oxidized to ultrathin films during a positive potential scan and were determined to be electrocatalytically active for oxidation of dimethylsulfoxide (DMSO) at vs. SCE when Bi 3+ was present in the test solutions.