Construction of Efficient Ru@NiMoCu Porous Electrode for High Current Alkaline Water Electrolysis

Abstract Alkaline water electrolysis is the promising technical pathway of large‐scale green hydrogen production. However, its hydrogen evolution reaction (HER) is hindered by the alkaline environment, leading to slow H2O splitting kinetics, especially for NiMoCu alloy catalysts which are considered potential alkaline HER catalysts. In this work, the Ru‐substrate modified NiMoCu20 porous electrode is designed by a continuous multistep electrodeposition method. It shows the good alkaline HER performance at the high current density of 1000 mA cm−2, which is attributed to the synergistic charge‐reconfiguration effects between Ru‐substrate and NiMoCu alloy by density functional theory (DFT) calculations and in situ Raman spectra analysis. It indicates that the Ru‐substrate is capable of encouraging H‐OH* bond breakage and optimizing transition‐state H* adsorption. Further, the overall water electrolysis results of the alkaline water electrolysis cell (30 wt% KOH) at 70 °C show that it has good performance at the large current density of 1000 mA cm−2 with 2.05 V and good stability at 600 mA cm−2 up to 500 h. It provides the possibility of designing the high‐performance HER electrode from the view of industrial applications.