Bridging Laboratory Catalysts with Industrial Proton Exchange Membrane Water Electrolyzers

The development of highly active catalysts has significantly advanced water electrolysis for green hydrogen production. However, translating these materials from laboratory‐scale demonstrations to industrial proton exchange membrane water electrolyzers (PEMWEs) remains a major challenge. In this perspective, key gaps are identified between academic electrocatalyst research for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in acidic media and the stringent requirements of industrial PEMWEs. The scalability and industrial relevance of current catalyst synthesis and electrode fabrication techniques are critically analyzed, proposing scalable routes such as plasma‐enhanced atomic layer deposition, roll‐to‐roll processing, and electrodeposition. The discrepancies in testing protocols between three‐electrode aqueous cells, membrane electrode assemblies and full electrolysis stacks are further discussed highlighting the challenges of making direct performance comparisons. To bridge this gap, relevant activity descriptors that connect catalyst properties with device‐level performance under industrial conditions are introduced, and critically highlight the importance of conducting both operando characterization and techno‐economic analysis. Finally, strategies to enhance both catalytic activity and durability, including electronic metal‐support interactions, porosity engineering, and single‐atom catalyst design, are highlighted. By integrating synthesis, testing, and mechanistic insights, this perspective offers a comprehensive roadmap to rationally design and implement next‐generation catalysts tailored for scalable, durable, and efficient industrial green hydrogen production.