Scalable electrodeposition of NiMoP for alkaline hydrogen production: From catalyst design to full-cell performance

The development of efficient and durable non-noble electrocatalysts with clear electrochemical functionality is critical for advancing alkaline water electrolysis. Herein, a binder-free electrodeposition strategy is introduced to directly deposit NiP, MoP, and ternary NiMoP electrocatalysts on nickel fiber film (NiFF), enabling intimate electrical contact and facilitating charge-transfer processes at the electrode–electrolyte interface. The incorporation of Mo into the Ni–P framework induces synergistic electronic interactions that modulate hydrogen adsorption and accelerate interfacial charge-transfer kinetics. Structural analysis confirms the preservation of the conductive FCC Ni framework and the formation of an interconnected NiMoP architecture that facilitates electrolyte accessibility. Electrochemical measurements in 1.0 M KOH reveal that NiMoP/NiFF exhibits low overpotential of 97.2 mV at 10 mA cm⁻² and Tafel slope of 120.5 mV dec⁻¹, indicating improved HER kinetics compared to binary counterparts. Impedance analysis further demonstrates reduced charge-transfer resistance, highlighting the role of compositional synergy in enhancing electron transport. The improved HER activity is associated with modified interfacial charge-transfer kinetics and optimized hydrogen adsorption energetics induced by Ni–Mo–P interactions. In a two-electrode configuration, the NiMoP-based electrolyzer achieves a cell voltage of 1.91 V at 50 mA cm⁻² with stable operation up to 250 mA cm⁻². Density functional theory (DFT) calculations reveal near-thermoneutral hydrogen adsorption energy, providing mechanistic insight into the optimized catalytic behavior. These findings establish a direct correlation between composition, electronic structure, and electrochemical performance, indicating NiMoP/NiFF’s applicability for alkaline hydrogen evolution.