Membrane Electrode Assembly Design for High-Efficiency Anion Exchange Membrane Water Electrolysis.

Growing interest in low-cost clean hydrogen production has positioned anion exchange membrane water electrolysis (AEMWE) as a leading sustainable technology. Its appeal lies in compatibility with platinum-group metal-free catalysts, inexpensive anode flow fields, and cost-effective bipolar plates. Recent advances in AEMWE focus critically on optimizing membrane electrode assembly (MEA) design to achieve industrially viable efficiency and durability. Key progress includes component-level innovations, such as developing nonprecious metal catalysts, fabricating anion exchange membranes (AEMs) with high ionic conductivity and alkaline stability, and engineering gas diffusion layers (GDLs) with hierarchical porosity for effective mass transport. Central to improving performance is interfacial engineering within the MEA, which combines catalyst layers (CLs), AEM, and GDLs to reduce ionic/charge transfer resistance and prevent mechanical delamination. A transformative breakthrough involves ordered, gap-free electrode assembly. This approach utilizes strategies such as ionomer-bonded architectures to establish continuous ion-conducting pathways or in situ catalyst deposition directly onto AEM surfaces, creating vertically aligned triple-phase boundaries. These ordered structures maximize catalyst utilization, markedly reduce voltage losses at industrially relevant current densities, and mitigate interfacial degradation during differential-pressure operation. Future advancements require scalable manufacturing of these ordered architectures to bridge material innovations with industrial deployment.