A “Two-Pronged” Strategy via Tungsten Doping and Heterostructure to Boost Hydrogen Evolution Reaction in pH-Universal Media

To broaden the applications of hydrogen production through water electrolysis, it is crucial to develop advanced electrocatalysts that can operate efficiently across a wide pH range. Herein, we propose a novel “two-pronged” strategy to construct W-doped CoP 3 /Ni 2 P heterogeneous electrocatalysts (W-CoP 3 /Ni 2 P) with well-defined nanowall morphology supported on nickel foam (NF) for efficient pH-universal hydrogen evolution reaction (HER). Benefiting from the manipulated electronic structure from W doping on the CoP 3 /Ni 2 P heterostructure, the positive synergy between the CoP 3 /Ni 2 P heterostructure and W doping, and the more accessible active sites offered by the interconnected nanowall structure, the resultant W-CoP 3 /Ni 2 P exhibits superior HER activities at all pH levels. The optimized W-CoP 3 /Ni 2 P requires an overpotential of 61, 75, and 135 mV to reach a current density of 10 mA cm –2 in alkaline, acidic, and neutral media, respectively, surpassing the CoP 3 /Ni 2 P and Ni 2 P counterparts. Density functional theory calculation revealed that the activity of the Ni site around the CoP 3 /Ni 2 P heterointerface was enhanced by introducing W heteroatoms to CoP 3 /Ni 2 P, significantly optimizing the water dissociation energy ( E H 2 O ), the energy barrier for the rate-determining step, and the hydrogen adsorption Gibbs free energy (Δ G H* ), thus accelerating the HER kinetics. This study provides novel insights into the design of promising HER electrocatalysts.