Interaction of Single-Atom Platinum–Oxygen Vacancy Defects for the Boosted Photosplitting Water H₂ Evolution and CO₂ Photoreduction: Experimental and Theoretical Study

Abstract

The incorporation of oxygen vacancy defects into the catalysts has been attracting significant interest for regulating the performance of photocatalysts. Single-atomic-site metal catalysts have also been paid ever-growing attention because they maximized the atom efficiency and thus generated excellent catalytic performance. Herein, we report the interaction of oxygen vacancy defects and decorated atomically dispersed metal Pt to boost the efficient photocatalytic process. Compared with TiO2 without oxygen defects, under the same theoretical amount of Pt support, all the oxygen vacancy defect-rich TiO2 catalysts show excellent photocatalytic H2 generation and CO2 reduction performance. On the basis of the experimental characterization and quantum chemical calculations, the introduced oxygen vacancies strongly anchored the single-atom Pt on the surface of the catalyst with enhanced Pt-substrate interactions and thereby avoiding aggregation of Pt atoms, while the loaded single Pt atom favor the generation of more surface and subsurface oxygen vacancies as proved by electron spin resonance and positron annihilation lifetime spectroscopy. This work represents a new heuristic research of the coeffect of the defects and supported single noble metal atom and the rational synthesis of high-efficiency photocatalysts.