Optimized mass transfer in a Pt-based cathode catalyst layer for PEM fuel cells

Abstract

Proton exchange membrane fuel cells have considerable potential to tackle climate and energy crises due to their clean and efficient energy conversion capabilities. However, their commercialization is hindered by the high costs associated with Pt-based electrocatalysts. Therefore, it is critical to reduce Pt loading without sacrificing the electrochemical performance. Yet, lower Pt loadings in the cathode catalyst layer result in mass transfer problems, particularly at high current densities, which substantially limit the development of low Pt PEM fuel cells. Herein, we highlight the mass transfer challenges and design strategies to address the problems such as ionomer film modification and catalyst layer interface optimization. We believe that this review will spur development in the design of catalyst layer structures to advance the development of PEM fuel cells.