Surface Sulfuration and Phosphorization Boosting Hydrogen Evolution Performance of Nickel Molybdate

Herein, the nickel molybdate nanorods arrays supported on Ni foam (NMO/NF) precursor were firstly fabricated by hydrothermal method. Then the surface sulfidation and phosphating for NMO/NF were conducted in turn, to obtain a three-dimensional self-supported electrode (PS-NMO/NF). The sulfidation induces the formation of amorphous sulfides with significantly enhanced electrochemical active area on the surface of nickel molybdate (S-NMO/NF), as well as a coral-like sphere structure. Phosphates were induced on the surface of sulfides by subsequent phosphating. The formed sulfides/phosphates heterogeneous interfaces can promote the electron transfer and improve the hydrogen evolution reaction (HER) performance of NMO. In 1 mol center dot L-1 KOH electrolyte, when the current density was 10 and 100 mA center dot cm(-2), the corresponding HER overpotential of PS-NMO/NF was 93 and 180 mV, respectively. The Tafel slope of PS-NMO/NF was 67 mV center dot dec(-1), and it had good stability within 20 h of running.