Heterogeneous VN/MoP Nanoparticles Embedded in a Nitrogen-Doped Carbon Framework Achieve Efficient Electrocatalytic Hydrogen Evolution

Amidst escalating global energy demands, the electrochemical hydrogen evolution reaction (HER) presents a sustainable pathway for clean hydrogen production. The rational design of heterostructured electrocatalysts is a promising strategy to overcome the inherent limitations of single-component catalysts for the hydrogen evolution reaction (HER). While vanadium nitride (VN) exhibits Pt-like electronic properties, insufficient electron density at V sites impedes hydrogen adsorption. Conversely, molybdenum phosphide (MoP) features a moderate Mo–P bond strength with intermediates, facilitating hydrogen desorption kinetics. Herein, we construct a VN/MoP heterointerface embedded in a nitrogen-doped carbon framework (VN/MoP@NC) via a one-step solid-phase sintering approach to synergistically modulate the electronic structures. Experimental results confirm that interfacial electron transfer from MoP to VN enriches the electron density of V sites, thereby optimizing the hydrogen adsorption free energy (ΔGH*). The heterojunction optimizes interfacial charge distribution and adsorption energetics, enabling an overpotential of 111 mV at 10 mA cm–2 in alkaline media with 50 h of stability. Furthermore, in a practical membrane electrode assembly (MEA), it delivers a high current density of 1000 mA cm–2 at a low cell voltage of 2.18 V for alkaline water electrolysis. This work not only demonstrates the effectiveness of electronic coupling in heterostructure engineering but also validates the catalyst’s promise for realistic hydrogen production.