TiCN-Coated Ti Felt for Enhanced Polymer Electrolyte Membrane Water Electrolysis

The gas diffusion layer (GDL) is an important component in polymer electrolyte membrane water electrolysis (PEM-WE), and Ti felt is often used as the GDL dueto its high stability. However, excessive passivation leads to a high surface contact resistance and energy loss during PEM-WE operation, thus limiting its practical application. In this work, we prepared low-cost TiCN-coated Ti felt GDL by a simple soaking and sintering method for the anode of the PEM-WE and determined a better immersion concentration of 48 g/L for the TiCN suspension. TiCN-coated Ti felt has a lower corrosion current density and a higher corrosion potential (0.37 μA cm^–2, 0.54 V_RHE), demonstrating better corrosion resistance performance. Compared with the untreated Ti felt, the interface contact resistance of the TiCN-coated Ti felt was significantly reduced to 1.73 mΩ·cm² at 150 N cm^–2, and it only increased to 2.51 mΩ·cm² after polarization for 100 h, showing improved stability. This provides an economical and efficient method for preventing the passivation of Ti-based GDLs and a new strategy for achieving low-cost large-scale water electrolysis for hydrogen production.