Composite-induced FeO(OH) phase transition as a highly efficient electrocatalyst for robust overall water splitting

Realizing efficient and stable overall water electrolysis is crucial for advancing efficient hydrogen production. However, developing electrocatalysts with both efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance under alkaline condition remains a significant challenge. Here, we report an innovative methodology for synthesizing FeO(OH)@NiC2O4 on nickel foam (NF) through a one-step hydrothermal method. Remarkably, FeO(OH)@NiC2O4/NF exhibits a remarkably low OER overpotential of 370 mV at a current density of 100 mA cm−2 and excellent electrochemical stability in OER. The cell voltage required for overall water splitting is lower than that of most reported catalysts. Detailed experiments reveal that the phase transition of FeO(OH) is induced through compositing, thereby significantly enhancing the catalytic performance.