Low platinum, high limiting current density of the PEMFC (proton exchange membrane fuel cell) based on multilayer cathode catalyst approach

Novel multilayer cathode electrodes structures for PEMFC (proton exchange membrane fuel cell) based on sputtering technique were developed to provide high performance with low loading Pt of 0.05 mg/cm² compared to the standard MEA (membrane electrode assembly) cathode (∼0.2-0.3 mg/cm²). Different configurations of cathode catalyst layer were made by altering Pt and CN (Carbon-Nafion) ink carefully prepared on gas diffusion layer containing MPL (micro porous layer). The performances of PEMFC containing the multilayer electrodes were compared based on their measured polarization curves. Higher limiting current densities were achieved compared to standard MEA with platinum loading of 0.2 mg/cm² both at the cathode and the anode sides. Limiting current densities over 1.1 A/cm2, 1.2 A/cm2 and 1.4 A/cm2 were reached whereas maximum powers were in the range of 500 mW/cm² at 600 mW/cm². The good performances obtained can be due to the structural improvement which has contributed to a better catalyst utilization compared to conventional methods. A CN loading inferior to 0.24 mg/cm² between each layer is preferred for multilayer electrode.