Experimental and Theoretical Understanding on Electrochemical Activation Processes of Nickel Selenide for Excellent Water-Splitting Performance: Comparing the Electrochemical Performances with M-NiSe (M = Co, Cu, and V)

Recently, bimetallic selenides have been proposed as robust water-splitting electrocatalysts toward the generation of low-cost sustainable fuels. Here, the first-principles theoretical prediction based on density functional theory combined with experimental research is used to design different transition metals (M = Co, Cu, and V) incorporated into NiSe (M- NiSe) for improving water-splitting performance. The different transition metals (M = Co, Cu, and V) doped into NiSe (M-NiSe) are prepared for the first time using a typical hydrothermal and selenylation method. Moreover, a cell voltage of 1.50 V is required when the V-NiSe and Cu-NiSe are used as anode and cathode catalysts to drive a current intensity of 10 mA cm(-2) for whole water splitting, which is, according to our literature research, lower than the most published selenide-based catalysts. Our work provides a promising methodology and theoretical predictions to design an environmentally friendly and robust catalyst for large-scale water-splitting applications.