Preparation of High‐Platinum‐Utilization Gas Diffusion Electrodes for Proton‐Exchange‐Membrane Fuel Cells

We evaluated an electrochemical catalyzation technique for producing gas‐diffusion electrodes for proton‐exchange‐membrane fuel cells (PEMFC). The electrochemical technique deposits platinum catalyst particles in regions of the electrode that are in ionic contact with the proton‐exchange membrane and in electronic contact with the carbon support. Since ionic and electronic contact are necessary components of catalyst utilization in gas‐diffusion electrodes, the electrochemical catalyzation technique reduces the amount of platinum required for PEMFC. We present data for oxygen reduction and hydrogen oxidation with gas‐diffusion electrodes containing 0.05 mg Pt/cm 2 .