Effective Hydrogen Evolution of Nickel–Molybdenum–Phosphide Electrodeposited Nickel Foam Electrode

Abstract

This study introduces an electrocatalyst composed of nickel-molybdenum-phosphide (NiMoP) supported on nickel foam (NiF), which has been synthesized using a straightforward two-step electrodeposition method intended for enhancing the efficiency of the hydrogen evolution reaction (HER) in alkaline environments. The addition of Mo and P, in contrast to traditional Ni-based catalysts, creates a synergistic electronic effect that considerably improves HER kinetics. The enhanced NiMoP/NiF catalyst demonstrates an impressively low overpotential of 171 mV at 10 mA cm⁻² and 376 mV at 100 mA․cm⁻², surpassing the performance of Ni/NiF (η₁₀ = 229 mV) and NiMo/NiF (η₁₀ = 181 mV). In comparison to current NiMoP systems, our catalyst exhibits superior catalytic activity, stability, and charge transfer efficiency. The electrochemical analysis indicates a Tafel slope of 119.98 mV․dec⁻¹, which supports a Volmer-controlled hydrogen evolution reaction mechanism characterized by enhanced water dissociation. The structural and compositional analysis demonstrates that Mo improves the electronic structure of Ni, whereas P increases water affinity and electrochemical surface area (C_dl = 3.18 mF·cm⁻²), which is almost four times higher than that of pristine NiF. The catalyst exhibits remarkable stability throughout 2000 cycles and shows reliable performance in multi-step chronopotentiometry evaluations. This study presents an economical, long-lasting, and scalable electrocatalyst for hydrogen evolution reaction, serving as a viable substitute for noble-metal-based systems in the pursuit of sustainable hydrogen production.

Graphical abstract