CoFeNi–P/NF ELECTROCATALYST WITH ENHANCED BIFUNCTIONAL ACTIVITY FOR EFFICIENT ALKALINE WATER SPLITTING
Аннотация
A rationally engineered ternary phosphide electrocatalyst CoFeNi-P/NF was developed through hydrothermal growth followed by controlled vapor-phase phosphorization to address the kinetic limitations of alkaline water splitting. Phosphorization induced profound electronic modulation and surface reconstruction of the CoFeNi nanosheet framework, generating defect-rich architectures and conductive metal-phosphide networks. The incorporation of phosphorus redistributed the electronic density of Co-Fe-Ni centers, optimized hydrogen adsorption energetics (ΔG_H*), and promoted in situ formation of catalytically active (oxy)hydroxide species during OER. Structural and compositional analyses confirmed uniform elemental distribution and preservation of the interconnected nanosheet morphology. Benefiting from synergistic multimetal interaction, enhanced charge-transfer kinetics, and increased electrochemically active surface area, the CoFeNi–P/NF electrode required only 132 mV for HER and 140 mV for OER at 10 mA cm-2 in 1 M KOH. Notably, the catalyst exhibited outstanding durability with negligible potential decay over 50 h of continuous operation at high current density. These results demonstrate that phosphorus-engineered ternary metal phosphides supported on 3D conductive scaffolds represent a scalable and efficient strategy for developing robust noble-metal-free electrocatalysts for sustainable hydrogen production.