Accelerating H* Desorption of Hollow Ni₂P/MoC Mott–Schottky Heterojunction for Hydrogen Evolution

Molybdenum carbide (MoC) with a Pt-like electronic configuration has emerged as a promising nonprecious electrocatalyst for the hydrogen evolution reaction (HER). However, its catalytic performance is hindered by an unfavorable Mo-H bonding strength. In this work, we integrated Ni₂P with MoC to establish Mott-Schottky heterojunction (MSH) for alkaline HER. The optimized Ni₂P/MoC nanoreactor achieves a low overpotential of 46 mV at 10 mA cm^-2, surpassing most reported MoC-based electrocatalysts. Moreover, the Ni₂P/MoC maintains excellent stability during 100 h of continuous operation at 100 mA cm^-2. Density functional theory (DFT) calculations reveal that MSH formation induces a downward shift of the d-band center relative to the Fermi level in Ni₂P/MoC, thereby promoting water molecule dissociation and H* intermediate desorption. This work presents a conceptual framework for the design of high-performance Mo-based electrocatalysts via interface-engineered electronic modulation.