Boosting water oxidation on Cu2V2O7 using atomic-scale frustrated Lewis pairs

Abstract

Photoelectrocatalytic water splitting is impeded by the high thermodynamic energy barriers and slow reaction kinetics of the anodic oxygen evolution reaction. Herein, a strategy for constructing frustrated Lewis pairs (FLPs) at the atomic scale to synergistically regulate both the thermodynamic and kinetic pathways of the reaction is proposed based on the systematic investigation of Cu₂V₂O₇ photoanodes. By introducing oxygen vacancies as Lewis acid sites, surface restructuring of Cu₂V₂O₇ is triggered, resulting in the formation of stable FLP architectures where terminal oxygen atoms serve as Lewis base sites. This atomic-level configuration enhances the transition kinetics of the *OH intermediate and reduces the thermodynamic barrier for O–H bond cleavage, thereby refining the electron–proton coupling process for water oxidation. At 1.23 V vs. RHE, the FLP-enhanced Cu₂V₂O₇ photoanode exhibits a 60% increase in photocurrent density relative to the unmodified sample, alongside outstanding catalytic stability. This study elucidates the atomic-scale synergistic mechanism of Lewis acid–base pairs in photoelectrocatalytic reactions, proposing innovative design principles and a theoretical foundation for developing highly efficient and stable photoelectrocatalytic materials.