Conductive Mechanism of Low-Pt-Coated Porous Transport Layers at Key Interfaces in Proton Exchange Membrane Water Electrolyzers

), when charge barriers exist at the PTL/CL interface, an uneven Pt coating fails to improve PTL/FF conductivity and instead introduces additional barriers─an effect that diminishes with optimized coating or increased current density. The charge barrier at the PTL/CL interface amplifies the negative effects at the PTL/FF interface; this effect can be mitigated by applying a uniform coating or increasing the current. These findings provide guidance for optimizing platinum-coated PTLs and for studying charge transport at the PTL/FF interface.