Investigation and Optimization of Pt/IrO2 Catalyst for Unitized Regenerative PEM Fuel Cells

A Unitary Regenerative Fuel Cell unites the function of a fuel cell and an electrolyzer. By using a single system investment costs can be reduced while extending the operability to a full-fledged energy storage system. Yet, to achieve such a functionality the catalyst must support both operation modes. Hence, this article focuses on the optimization of a bifunctional Pt/IrO2 catalyst in terms of chemical activity for the use in URFCs. The results show that an increased material load leads to a higher power output but the current density remains low. Therefore, a novel approach is presented to increase the active surface area and improve the binding of the active particles through the use of SiC as a carrier material. It is shown that active Pt and IrO2 particles can be deposited on the carrier material, which results in an increase of the mass activity by up to 90%.