OXYGEN REDUCTION KINETICS ON A PLATINUM RDE COATED WITH A RECAST NAFION1 FILM

Measurements of currents of the oxygen reduction reaction (ORR) at a Pt RDE coated with a recast Hafion film yield the permeability of O//2 through such films. Combined with results from linear potential scanning experiments on similar electrodes, these measurements also allow the separate evaluation of the concentration of O//2 and its diffusion coefficient in such films. Similar recast Nafion films have been used successfully to promote protonic access to catalyst sites in fuel cells. Accordingly, the maximum film thickness which would allow adequate oxygen flux through such a layer is evaluated.