Engineering anode porous transport electrode design for enhanced anion exchange membrane water electrolysis performance

Abstract The advancement of efficient anion exchange membrane water electrolyzers (AEMWEs) necessitates precise engineering of electrode structures and interfacial properties to enhance performance. In this study, we systematically design and evaluate key engineering parameters of porous transport electrodes, including compression conditions, catalyst layer composition, and porous transport layer (PTL) structures. By optimizing compression conditions, we achieve improved membrane–electrode contact, minimizing interfacial resistance and enhancing electrochemical efficiency. A tailored catalyst layer composition with an optimized ionomer‐to‐catalyst ratio (7.5–10 wt.%) ensures a balance between ionic conductivity and catalyst accessibility, improving charge transport. Additionally, structural modifications in PTLs highlight the critical role of surface and bulk morphology in determining interfacial contact and mass transport characteristics. A novel hierarchical PTL design, integrating a bilayer structure with graded surface and bulk properties, successfully decouples competing interfacial and transport requirements, achieving a current density of 3.06 A cm − 2 at 1.8 V. These findings underscore the significance of engineering porous transport electrodes to optimize AEMWE performance, offering valuable insights for the development of next‐generation high‐efficiency water electrolyzers.