Dual‐Type Ru Atomic Sites for Efficient Alkaline Overall Water Splitting

Abstract Monotypic catalytic site for bifunctional hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at low overpotential is a grand challenge in alkaline water splitting. Herein, a new strategy of dual‐type atomic site‐support interaction is reported, in which ruthenium heteroatoms are in situ implanted into both the N‐C nanosheet matrix (Ru 1 ‐N‐C) and supported Co 2 P nanoparticle lattice (Ru 2 ‐P‐Co) for boosting alkaline water splitting. It is found that the Ru 1 ‐N‐C and Ru 2 ‐P‐Co can give rise to a synergistic effect for boosting HER and OER catalysis. Density functional theory calculations disclose that for HER, the Ru‐functionalized Co sites in Co 2 P assume the task of expediting H 2 O adsorption‐dissociation, and the adjacent coordination unsaturated Ru 1 ‐N‐C sites can facilitate the following H 2 desorption kinetic. The study found that the hydrogen spillover mechanism contributes to an ultralow HER polarization of 69 mV at 10 mA cm −2 . While for OER, due to electronegativity discrepancies, the doped Ru within Co 2 P triggers electronic coupling, thereby efficiently tuning Ru d ‐band center. This grants its electronic characteristic preferred for modulating rate‐determining step of OER to reduce the corresponding energy barrier, leading to superior OER catalytic activity . This work offers new understandings into catalyzing different reactions with multiple intermediate adsorptions by different atomic site‐support interplays.