CoCrNi‐Based High‐Efficiency High‐Entropy Alloy Nanoelectrocatalysts Al_0.3Cu_0.1(CoCrNi‐X)_0.6 for OER Application

Abstract To find nonprecious metal high‐entropy alloy nanoparticles (HEA‐NPs) electrocatalysts that perform even better in electrolytic water OER and to learn more about the reasons for their superior performance. This experiment successfully prepared nanocatalysts Al 0.3 Cu 0.1 (CoCrNi‐X) 0.6 (X = Mo, Ti and V) by simple mechanical ball milling. The electrocatalyst Al 0.3 Cu 0.1 (CoCrNiMo) 0.6 exhibits excellent reaction kinetics, with an overpotential of only 243 mV and a Tafel slope of 191.59 mV·dec −1 at a current density of 10 mA·cm −2 . It also has a low impedance that hinders charge transfer during catalysis and can maintain catalytic stability for over 50 h. It has better catalytic activity than the other three catalysts, which is attributed to fine nanostructure and complex duplex crystal structure (FCC + BCC), resulting in the specific surface area of the electrocatalyst having more catalytic active sites as well as the synergistic promotion of Mo and other elements, which was the most conducive to accelerating the OER. This indicates that the element Mo is the optimal catalytic doping element among the above three elements, followed by V and Ti, which is significant in the field of doping catalytically active elements in nanostructured HEA electrodes to enhance the performance of catalysts for OER and energy conservation.