Effect of Pt and Ionomer Distribution on Cell Performance and Durability

Further improvement in initial performance and durability is required for the widespread use of polymer electrolyte fuel cells. So far, many researchers reported that the position of Pt particles affects ORR activity and cell performance in a catalyst using carbon black (CB) as a support. In recent years, the focus has been on creating a catalyst structure and ionomer coating that maximizes Pt utilization by supplying protons and oxygen to the surface of Pt particles, but the guidelines for maximizing Pt utilization are not clear. In addition, since the durability test is performed by sweeping the potential under H2 / N2 conditions, the influence of generated water cannot be taken into consideration, and it is considered that the deterioration of the catalyst due to actual operation is different. In this study, the coating state of ionomer was considered from the results of N2 gas adsorption measurements, and the design guidelines for maximizing the Pt utilization rate were examined. Furthermore, an actual load cycling test was conducted under H2 / air conditions to investigate the effect of the catalyst structure on the deterioration of cell performance.