Comparative study of protonic conducting polymers incorporated in the oxygen electrode of the PEMFC

The kinetics of the reduction of oxygen at the surface of a platinum disc covered with thin layers of polymer has been studied in 0.5 M H 2SO 4 at ambient temperature in order to establish to what extent the polymer affects the reaction mechanism. Experiments were performed particularly to determine the oxygen permeability D f C f (product of the diffusion coefficient and the oxygen concentration in the film) for Nafion ® and other polymers such as sulfonated polyimide (PIS), sulfonated polyetherketone (PEEKs) and non-sulfonated polybenzimidazole (PBI). The product D f C f depends on the nature of the polymer. Furthermore, how well the active layer works depends markedly on the amount of polymer it contains.