Strong electronic metal-support interaction of Ni4Mo/N-SrMoO4 promotes alkaline hydrogen electrocatalysis

Ni 4 Mo electrocatalyst stands out as the promising candidate for hydrogen evolution/oxidation reaction (HER/HOR), yet the intensive hydrogen adsorption leads to sluggish kinetics, decreasing hydrogen catalysis efficiency. Herein, the structure of Ni 4 Mo nanoparticles anchored on wafer-biscuit-like N-SrMoO 4 nanorods (Ni 4 Mo/N-SrMoO 4 ) is developed to accelerate reaction kinetics by modulating electronic structure. The designed N-SrMoO 4 support enables strong electronic metal-support interaction with Ni 4 Mo, resulting in a downward shift of d -band center and achieving thermally neutral hydrogen adsorption. Ni 4 Mo/N-SrMoO 4 exhibits HER performance with an ultralow overpotential of 15 mV at 10 mA cm −2 , superior to Pt/C ( η 10 =18 mV). The outstanding exchange current density of 10.2 mA cm −2 for HOR is three times higher than that of Pt/C (3.5 mA cm −2 ). Ni 4 Mo/N-SrMoO 4 is further assembled in anion exchange membrane water electrolyzer (AEMWE), resulting in a current density of 100 mA cm −2 at voltage of 1.71 V and the excellent stability of 300 hours. Theoretical calculations and in-situ spectroscopy indicate that the introduction of Sr in N-SrMoO 4 effectively enhances electronic metal-support interaction, facilitates the enrichment of adsorbed hydroxyl (OH ads ) on active sites and weakens hydrogen adsorption on Ni 4 Mo, thereby accelerating reaction kinetics of hydrogen electrocatalysis.