Dynamic water network reconfiguration via oxyphilic V dopants enables industrial-current-density alkaline hydrogen evolution

초록

The sluggish kinetics of alkaline hydrogen evolution reaction (HER) at industrial-current densities stem from rigid interfacial water structures that impede water dissociation and hydroxyl (OH−) transfer. Here, we engineer vanadium single-atom-doped CoP (VSA-CoP) to dynamically reconfigure hydrogen-bond networks at the catalyst-electrolyte interface. Through combined ab initio molecular dynamics and in situ Raman spectroscopy, we demonstrate that oxyphilic V Lewis acid sites disrupt ice-like water clusters, liberating free water molecules and increasing interfacial water mobility. This optimized microenvironment synergistically facilitates HO–H bond cleavage and enables rapid OH− diffusion via a K+-assisted Grotthuss mechanism, mitigating OH* poisoning while accelerating reaction kinetics. The VSA-CoP catalyst achieves an ultralow overpotential of 266 mV at 1000 mA cm−2 in alkaline media and sustains >300 h stability at 100 mA cm−2, surpassing commercial Pt/C. This work deciphers the critical role of interfacial water dynamics in high-current-density electrocatalysis, providing a universal strategy for catalyst design via microenvironment control.

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