Superhydrophilic and superaerophobic Ni–Mo alloy grown on 3D Ni foam with heterogeneous structure as self-standing electrocatalysts toward efficient alkaline HER

Hydrogen energy is the most promising clean energy at present and hydrogen production by electrocatalytic water splitting is the frontier technology of alternative energy in the future. Herein, the Ni–Mo alloy supported with nickel foam (NF) was prepared by hydrogen reduction strategy at high temperature. The catalytic activity and stability of NiMo@NF-x catalyst (x stands for temperature) with multistage (sheet/particle) array structure were studied under different temperatures. The performance of the catalyst was evaluated by contact angle and related electrochemical characterization. It was found that the surface of NiMo@NF-550 catalyst prepared at 550 °C had superhydrophilic and superaerophobic properties, which contributed to the deactivation of bubbles from the surface of the electrode and improved the efficiency of the catalytic reaction. Moreover, the multi-stage array structure of sheet/particle will form a greater specific surface area than the plain sheet structure, offering more reaction sites. These results indicate that the self-supported superhydrophilic and superaerophobic Ni–Mo catalysts have excellent electrocatalytic hydrogen evolution ability.