Facile photochemical construction of surface oxygen vacancies on polar BiOIO3 for enhanced CO2 photoreduction performance

Abstract

With the increase in global carbon emissions, environmental problems are becoming increasingly severe. Photocatalytic CO₂ reduction, as a green technology, holds promise for converting CO₂ into fuels and achieving carbon cycling, thus attracting much attention. The novel BiOIO₃ has a suitable band structure, high separation efficiency of photogenerated carriers, and strong CO₂ adsorption and activation capabilities, showing significant advantages in the field of photocatalytic CO₂ reduction. In this study, a defect engineering modification strategy for BiOIO₃ was carried out by means of ultraviolet light irradiation at room temperature and pressure. This achieved flexible regulation of the band structure of photo-induced oxygen vacancy containing BiOIO₃ and enhanced its photocatalytic CO₂ reduction performance. Through a series of experimental characterizations and DFT theoretical calculations, the formation mechanism of photo-induced oxygen vacancies and the electron transfer behavior of oxygen vacancies in the photocatalytic CO₂ reduction reaction were revealed. It was demonstrated that photo-induced oxygen vacancies can effectively improve the utilization efficiency of carriers and enhance CO₂ adsorption and activation. The research findings provide a new perspective for defect engineering in the design and application of energy conversion materials.