A Review on the Oxygen Transport for High PerformancePEMFCs at Low Pt Loadings

In order to promote the commercialization of polymer electrolyte membrane fuel cells (PEMFCs), it is necessary to decrease the consumption of Platinum (Pt) in the cathode catalyst layers (CCLs). The high oxygen mass transfer resistance in CCLs and the low reaction activity of Pt‐based catalysts are recognized as major stumbling blocks to achieving low‐Pt PEMFCs of high performance due to the obvious mass transfer polarization, particularly at large current density (HCD) region, and the loss of activation polarization. This review analyzes the impact of oxygen mass transfer behaviors and perfluorinated sulfonic acid (PFSA) ionomer on the performance of low‐Pt PEMFCs. Strategies for mitigating these negative effects are summarized, including structure design of ionomer and catalyst layer, regulation of ionomer distribution, and optimization of the interface between Pt nanoparticles (NPs) and ionomer molecular chains. The provided insights can be applied to develop fuel cells with high efficiency at low Pt loading.