Microstructural Design of PEFC Electrocatalyst Layer Using Mesoporous Carbon

Heavy-duty applications of polymer electrolyte fuel cells (PEFCs) require improved activity and durability of the cathode electrocatalysts. The nanostructure and microstructure of the catalyst layer both significantly affect PEFC performance. Mesoporous carbons (MC) have mesopores which have been shown to suppress ionomer poisoning, when used as a catalyst support, leading to higher catalytic activity. Here, we compare the initial performance of single cells using Ketjen black (KB) and MC catalyst supports. Furthermore, the fuel cell performance is evaluated using Pt-Ta-Co alloy-based catalyst decorated on MC. Pt-Ta-Co/MC electrocatalyst exhibits high cell performance in a low current density range. However, cell performance at high current densities has yet to be improved due to non-uniform microstructure of the Pt-Ta-Co/MC electrocatalyst layer.