Functionalized 3D Mo2N Current Collectors Drive Multi-Phase Ni-based Synergy and Mitigate Surface Reconstruction for Enhanced Oxygen Evolution Catalysis

Electrochemical water splitting is a promising approach for sustainable hydrogen production, but the oxygen evolution reaction (OER) remains a bottleneck due to sluggish kinetics, poor activity, and limited stability and scalability. Here, a Mo 2 N-functionalized nickel is designed foam (NF@Mo 2 N) and subsequently transform into a Mo 2 N/NiSe/Ni 2 P multi-phase heterostructure through selenization and phosphorization, to address these challenges. The optimized NF@Mo 2 N/NiSe/Ni 2 P catalyst integrates three key strategies: (I) functionalizing NF with Mo 2 N to enhance conductivity and charge transfer, (II) engineering a collaborative multi-interface heterostructure to optimize active sites and reaction kinetics, and (III) precisely controlling phase formation through selenization and phosphorization to mitigate surface reconstruction and ensure long-term stability. The catalyst not only achieves an overpotential of 242 mV@10 mA cm −2 and remarkable stability over 350 h, but also achieves a low overpotential of 395 mV at a high current density of 800 mA cm −2 , outperforming the pristine other control samples. Theoretical analysis reveals that the Mo 2 N-stabilized NiSe/Ni 2 P heterostructure on NF enhances conductivity and optimizes adsorption energies of OER intermediates, leading to improved catalytic performance and stability. This work provides a new strategy for designing high-performance, non-precious metal OER catalysts for industrial applications and advancing sustainable hydrogen production.