A Dual-Interlocked Electrocatalyst Design Principle for Durable AEM Water Electrolysis at Industrial Current Densities

Abstract

Achieving practical anion exchange membrane water electrolysis (AEMWE) requires hydrogen evolution catalysts that remain active and durable at industrially relevant current densities, where vigorous gas evolution accelerates catalytic-site degradation and multiscale interfacial failure. Here, we report a dual-interlocking electrocatalyst interface design method that integrates the current collector, catalyst support, and active sites into a mechanically and electronically coherent architecture to address these issues. A graphdiyne-mediated hierarchical interlock promotes the interpenetrated growth of vacancy-rich distorted NiTe on nickel foam, enabling robust collector–support coupling and low interfacial resistance, while a spatial interlock locally confines ultrasmall Ru clusters within defect-rich NiTe domains through Ru–Ni/Te coordination and defect-mediated confinement, mitigating migration, aggregation, and active-site loss. The catalyst exhibits a low overpotential of 60.5 ± 13.9 mV at −1.0 A cm–2 and operates stably for over 10,000 h and 3500 h at −1.0 and −2.0 A cm–2, respectively, in 1 M KOH. In a practical AEMWE device (80 °C, 4 cm2), the electrolyzer delivers 1.79 V at 3.0 A cm–2, meeting the U.S. DOE 2026 low-temperature electrolysis stack target, and sustains continuous operation for 1,030 h and 4100 h at 1.0 and 2.0 A cm–2, respectively. This work provides a broadly applicable electrode-architecture strategy for stabilizing high-rate gas–liquid–solid electrochemical interfaces through multiscale dual interlocking.