One-step electrodeposition of W, Mo-Ni3S2/NF catalyst: an efficient hydrogen evolution electrode for alkaline media

Abstract

A self-supported tungsten (W), molybdenum (Mo)-Ni₃S₂/nickel foam (NF) hydrogen evolution reaction (HER) electrode was successfully fabricated on NF via constant current electrodeposition. The morphology, elemental composition, and electrocatalytic HER performance of the electrodes were systematically characterized via scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and an electrochemical workstation. Results indicate that the surface of the W, Mo-Ni₃S₂/NF electrode consists of rough and refined nano-spherical particles with certain amorphous characteristics. In 1 M KOH, the W, Mo-Ni₃S₂/NF electrode demonstrates superior catalytic HER activity and stability. In particular, it achieves an overpotential of only 76 mV at a current density of 10 mA cm⁻². After undergoing 2000 cyclic voltammetry cycles and 12 h of continuous electrolysis, the electrode retains its high HER activity. The nano-spherical morphology and coexistence of amorphous/crystalline structures significantly enhance the electrochemical active surface area and expose more catalytic active sites. Moreover, the incorporation of W and Mo effectively modulates the electronic structure of Ni₃S₂, reducing charge transfer resistance, and consequently, enhancing the overall HER catalytic performance of the electrode.