A Materials-Based Mitigation Strategy for SU/SD in PEM Fuel Cells: Properties and Performance-Specific Testing of IrRu OER Catalysts

Catalysts that enable proton exchange membrane fuel cells to weather the damaging conditions experienced during transient periods of fuel starvation have been developed. The addition of minute amounts of iridium and ruthenium to the cathode enhances the oxygen evolution reaction (OER) during start-up/shutdown events, thus lowering the peak cell voltage closer to the onset of water oxidation. The catalyst loadings ranged from 1 to 10 μg/cm2, but showed surprisingly high activity and durability. At such low loadings, it is possible to fully integrate the OER catalysts with negligible interference on fuel cell performance and a marginal increase in catalyst cost.