Synergistic electronic modulation in C@NiCoP-Fe/NF accelerates intermediate adsorption kinetics for enhanced oxygen evolution

Water electrolysis has emerged as a sustainable method for clean hydrogen production. Nevertheless, the intricate four-electron nature and sluggish kinetics of the oxygen evolution reaction (OER) at the anode persist as significant impediments. Despite the evident potential of transition metal phosphides, their propensity for the adsorption of the *OH intermediate, as well as the consequent high RDS energy barrier, remain pivotal concerns that necessitate resolution. This work proposes a dual electron regulation strategy to construct a transition metal phosphides OER catalyst. The resulting C@NiCoP-Fe/NF catalyst delivers remarkable OER performance with overpotentials of only 267 mV (10 mA cm⁻²) and 363 mV (100 mA cm⁻²), exceeding most existing NiCo-based counterparts. A 1000-h constant-current test at 10 mA cm⁻² also ascertains the stability. In-situ characterization and density functional theory (DFT) calculations reveal that phosphorization (P) carbonizes the organic framework, forming a conductive carbon layer. Mechanistically, the high electronegativity of P induces electron-deficient NiCo sites to promote OH⁻ adsorption, while Fe doping triggers metal–metal interactions that modulate the d-band center to lower the energy barrier of the rate-determining *O to *OOH step. This work provides comprehensive insights into the dual electron regulation mechanism for OER through phosphorization and Fe doping.