Construction of Ru/Fecop Heterointerface to Drive Dual Active Sites Mechanism for Efficient Overall Water Splitting

The interface engineering strategy is deemed to be a direct approach for boosting water splitting, but it is still a challenge to have both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activities exceeding precious-metal catalysts. Herein, the maneuverable photodeposition is utilized to construct Ru@FeCoP with rich Ru/FeCoP heterointerfaces. Strikingly, the η100 value of Ru@FeCoP is merely 0.0741 V for HER and 0.314 V for OER, achieving 1.76-fold and 1.23-fold improvement over Pt/C and RuO2 benchmark, respectively. Mechanism investigation unveiled that Ru at the Ru/FeCoP heterointerfaces not only offers highly-active sites for HER but also pull electrons from FeCoP, which facilitates the generation of Fe and Co with high valence and thereby raising OER activity. This work settles the problem of low water-splitting efficiency in precious-metal via constructing a metal/phosphide heterostructure to drive a dual-active sites mechanism and provides an effective route for the preparation of high-performance water-dissociation electrocatalysts.