An Alloy Nanowire-Based Water Splitting Electrode Adapting Fluctuating Electric Power Input

Water electrolysis is a promising strategy for storing surplus renewable electricity in the form of green hydrogen. However, the intermittent nature of renewable power causes frequent start-stop cycles in electrolyzers, inducing reverse current, which accelerates catalyst degradation and compromises electrode durability. Despite its long-standing industrial relevance, the understanding of irreversible damage mechanisms under dynamic cycling and effective mitigation remains limited. Here, a self-supported ternary alloy nanowire electrode is presented with exceptional tolerance to intermittent operation via synergistic structural and electronic regulation. The assembled anion membrane electrolyzer delivers a low cell voltage of 2.33 V at 4 A cm⁻² and maintains stable performance over 900 h at 1 A cm⁻². Under 2000 cycles of intermittent reverse current, the ternary alloy electrode exhibits ≈40% lower voltage decay than its binary NiFe counterpart. The nanowire architecture, combining high surface area and mechanical flexibility, facilitates efficient gas bubble release and alleviates local stress. Incorporation of cobalt stabilizes active sites by increasing vacancy formation energy and tuning the electronic structure, thereby mitigating degradation caused by reverse current pulses. This work establishes a benchmark for reverse-current adaptive electrode design for water splitting, promoting stable hydrogen production and storage under intermittent renewable energy sources. © 2025 Wiley-VCH GmbH.