Study on corrosion migrations within catalyst-coated membranes of proton exchange membrane electrolyzer cells

The corrosion of low-cost, easily manufactured metallic components inside the electrochemical environment of proton exchange membrane electrolyzer cells (PEMECs) has a significant effect on their performance and durability. In this study, 316 stainless steel (SS) mesh was used as a model liquid/gas diffusion layer material to investigate the migration of corrosion products in the catalyst-coated membrane of a PEMEC. Iron and nickel cation particles were found distributed throughout the anode catalyst layer, proton exchange membrane, and cathode catalyst layer, as revealed by scanning transmission electron microscopy and energy dispersive X-ray spectroscopy. The results indicate the corrosion products of 316 SS are transported from anode to cathode through the nanochannels of the Nafion membrane, resulting in impeded proton transport and overall PEMEC performance loss. •Metal cations are found throughout PEMEC catalyst-coated membranes.•Fe/Ni cations inside membrane occupy the water channels which severely inhibit proton transport through the membrane.•Uptake into the MEA from Fe–Cr–Ni 316 stainless steel follows Fe ≫ Ni ≫ Cr.