NiCo layered double hydroxides derived Ni_0.67Co_0.33(PO₃)₂ as stable and efficient electrocatalysts for overall water splitting

The synthesis of highly efficient non-noble bifunctional electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in the same electrolyte is important for the industrial application of electrocatalytic water splitting. Herein, non-noble bifunctional electrocatalyst Ni_0.67Co_0.33(PO₃)₂ nets with optimized morphology were successfully synthesized. Owing to the micropores with the accelerated electrolyte and gases transfer and nanopores architecture with more exposed active edge sites, the self-supported Ni_0.67Co_0.33(PO₃)₂-12 h electrode exhibits a superior water splitting performance. Impressively, the Ni_0.67Co_0.33(PO₃)₂-12 h electrode only needs a cell voltage of 1.46 V to achieve 10 mA/cm² and shows over 22 h stability at 10, 50 and 100 mA/cm², respectively. This present work suggests a unique and earth abundant material synthesis method for water electrolysis, which has broad prospects for practical water splitting application.