Crystallographic orientation regulation of magnesium deposition enabled via nickel phosphide Nanoarray Interface toward stable magnesium metal anodes

The crystallographic orientation of magnesium deposition is closely related to interfacial interactions between the substrate and deposited metal, which critically influences the morphology evolution and reversibility of magnesium metal anodes. Herein, vertically aligned nickel phosphide nanoarrays grown on nickel foam (Ni₂P@NF) are constructed to regulate the nucleation and growth behavior of magnesium at the electrode–electrolyte interface. Density functional theory calculations reveal that the Mg (002)/Ni₂P interface possesses the lowest interfacial formation energy and favorable adsorption characteristics, enabling preferential Mg nucleation along the thermodynamically favorable Mg (002) plane. The low lattice mismatch between Mg and Ni2P further promotes the epitaxial growth of Mg (002), achieving a smooth and dense magnesium deposition layer. Experimental observations confirm that magnesium deposition on Ni₂P@NF exhibits highly uniform morphology and significantly improved reversibility compared with pristine NF. The Ni₂P@NF electrode delivers a reduced nucleation overpotential and stable magnesium plating/stripping behavior for over 1260 h at 1 mA cm⁻². Furthermore, full cells paired with a Mo₆S₈ cathode exhibit enhanced rate capability and long-term cycling stability. This work provides new insights into crystallographic regulation of metal deposition at heterogeneous interfaces and offers an effective strategy for stabilizing magnesium metal anodes.