STUDY OF THE OXYGEN ELECTRODE MECHANISM

Results of capacity, voltammetry, polarization, and rest potential studies on platinum in acidic and basic solutions are described. The implication of these results in terms of oxygen elec trode kinetics are discussed. It is concluded that - Adsorbed oxygen cannot be detected by equilibrium capacity measurements on smooth platinum electrodes. Adsorbed oxygen on smooth platinum as detected by voltammetry methods is subject to displacement depending on the purity of the solution. Surface migration is a possible source of reducible oxygen only in restricted spaces. Experiments in a bulk solution with nonrestricted transport show no measurable surface migration component. By subjecting the electrode to a strongly preoxidizing environment, absorbed oxygen is detectable by capacity measurement. It is assumed that in this condition the surface is covered with a conducting oxide layer upon which oxygen is adsorbed. (Author)