Constructing Ru-Co₂P Lewis Acid-Base Pairs to Prompt Hydrogen Evolution Reaction in Alkaline Seawater Electrolyte

Seawater electrolysis is an ideal approach to generating green hydrogen. Nevertheless, the sluggish kinetics of water dissociation and the detrimental chlorine chemistry environment are serious obstructions for industrial applications. Herein, constructing unique (Co) Lewis acid and (Ru-P) base pair sites in Ru-Co₂P decorated on nitrogen and phosphorus co-doped carbon (Ru-Co₂P/NPC) significantly optimizes the energy barrier of water dissociation and enhances the anti-corrosive ability for alkaline seawater splitting. As expected, the optimal Ru-Co₂P/NPC-2 exhibits exceptional hydrogen evolution reaction (HER) performances with overpotentials as low as 22.0 and 26.0 mV to derive 10 mA cm^-2 and operate steadily (@ 50 mA cm^-2) over 30 h in alkaline and alkaline seawater electrolytes. The experimental and theoretical results elucidate that Co acting as Lewis acid sites prompts the water adsorption and breakage of the H─O bond, whereas Ru-P as Lewis base sites facilitates the hydrogen desorption in alkaline media. Furthermore, modulated chemical microenvironments can be beneficial to hinder chloride corrosion on the active sites of catalysts. This work sheds light on the rational construction of a highly efficient electrocatalyst for alkaline HER in seawater.