Laser Co‐Patterning Redefines Interface Engineering for High‐Efficiency and Durable Water Electrolysis

ABSTRACT Proton exchange membrane water electrolysis is a critical pathway for hydrogen production, yet its efficiency and durability are constrained by the interfacial transport limitations within the cell. However, conventional approaches only focus on individual component or interface. Herein, we introduce an integrated design strategy that establishes the continuous transport pathway across the membrane electrode assembly by simultaneously laser patterning of gas diffusion layer (GDL)‐catalytic layer (CL) and proton exchange membrane (PEM)‐CL interface. Computational fluid dynamics and molecular dynamics simulations reveal the patterning on GDL promotes apparent kinetics and mass transport. Concurrently, laser patterning and subsequent acid treatment of the PEM enhance proton transport by facilitating the improved connectivity of water channels. Electrolytic cells assembled with the laser‐patterned GDL and PEM demonstrate an exceptional performance enhancement, achieving 1.90 V at 3 A/cm 2 —a 37.09% voltage reduction and 28.94% increase in electrolysis efficiency. Furthermore, the laser co‐patterned cells demonstrated a voltage decay rate of only 6.15 µV/h during a 1000‐hour durability test, an order of magnitude lower than unpatterned counterparts. This work establishes a novel design principle for the electrolyzer by creating an integrated mass transport pathway within the cell via laser patterning and demonstrates its transformative performance with a clear mechanistic insight.