A Universal Strategy to Metal Wavy Nanowires for Efficient Electrochemical Water Splitting at pH‐Universal Conditions

Abstract While overall water splitting is considered as one of the most efficient approaches for sustainable oxygen and hydrogen generations, the design of robust electrocatalysts that are active and stable for overall water splitting in pH‐universal conditions is still a significant challenge. Herein, a universal strategy for a class of metal wavy nanowires (NWs) for the enhanced electrocatalysis is reported. Benefiting from the structural features of ultrathin nature and numbers of defects, the obtained NWs generally exhibit attractive performances in oxygen evolution reaction (OER) and hydrogen evolution reaction at pH‐universal conditions. More significantly, the optimized Ru O 2 NWs‐Ir NWs electrolyzer shows superior performance for overall water splitting with only cell voltages of 1.50 and 1.47 V in 0.05 and 0.5 m H 2 SO 4 and 1.56 and 1.49 V in 0.1and 1 m KOH at 10 mA cm −2 , much lower than those of the Ir/C‐Pt/C electrolyzer. First‐principles calculations reveals that the appearance of Ru‐atom point defects on RuO 2 (200) surface will lower the OER overpotential during which the adsorption free energies of OER intermediates are weakened due to the right‐shift of d‐band center. The RuO 2 NWs‐Ir NWs electrolyzer also exhibits excellent durability in long‐term electrolysis, showing exciting prospect for water splitting in different pH electrolytes.