The Effects of Cathode Parameters on the Performance of Poly(2,5-Benzimidazole)-Based Polymer ElectrolyteMembrane Fuel Cell

The effects of electrode parameters on membrane electrode assembly performance including Pt loading, hydrophobicity during heat treatment, catalyst layer thickness and the amount of polytetrafluoroethylene (PTFE) in the cathode are investigated. The fuel cell performance is maximized via catalyst utilization by optimizing the phosphoric acid content in the electrodes. Heat treatment of gas diffusion electrode results in an increase in hydrophobicity and a decrease in phosphoric acid content in the catalyst layer, which drastically affects the fuel cell performance. In our conditions, a maximum fuel cell performance of 270 mW cm−2 was achieved at 160 °C with air using 1 mg Pt cm−2 total catalyst loading (20 % PTFE). The fuel cell performance and the poisoning effect of carbon monoxide in poly(2,5-benzimidazole) (ABPBI)-membrane-based high-temperature membrane electrode assemblies were investigated with respect to carbon monoxide concentrations. Fuel cell performance of Pt alloys (Pt-Cu/C, Pt-Fe/C, Pt-Ni/C) is compared with that of Pt/C at temperatures between 140 and 180 °C. It was observed that Pt-Cu/C alloy catalysts exhibit higher performance with lower catalyst loadings (0.4 mg Pt cm−2) than Pt/C catalyst. The performance of alloy catalysts follows the order of Pt-Cu/C> Pt-Fe/C>Pt-Ni/C>Pt/C.