Superhydrophilic/superaerophobic amorphous NiS/NiMoS electrocatalyst for enhanced hydrogen evolution.

It is important to develop electrocatalysts that are cheap and have high activity for hydrogen evolution reaction (HER). In this work, NiS/NiMoS with amorphous phase and unique candied-haws shaped nanoarray structure was successfully grown on nickel foam (NiS/NiMoS/NF) as efficient HER catalyst. Combining NiS with NiMoS resulted in the extension of the heterointerfaces between the materials, which facilitated the HER process in alkaline medium. The amorphous NiS/NiMoS with disordered atom arrangement provided abundant active sites. Also, the unique morphology of the catalytic electrode simultaneously enabled it exhibit superhydrophilicity and underwater superaerophobicity. It is beneficial for the sufficient diffusion of the electrolyte onto the catalyst surface and the fast departure of hydrogen bubbles from the surface. As a result, the activity of NiS/NiMoS/NF was higher than that of Pt/C even at high current densities. It is very valuable for industrial applications that require high current density. The superior stability of NiS/NiMoS/NF compared to Pt/C further demonstrated that this catalytic electrode has potential for industrial applications.