| Summary: | The weak adsorption of CO<sub>2</sub> and the fast recombination of photogenerated charges harshly restrain the photocatalytic CO<sub>2</sub> reduction efficiency. The simultaneous catalyst design with strong CO<sub>2</sub> capture ability and fast charge separation efficiency is challenging. Herein, taking advantage of the metastable characteristic of oxygen vacancy, amorphous defect Bi<sub>2</sub>O<sub>2</sub>CO<sub>3</sub> (named BO<sub>v</sub>C) was built on the surface of defect-rich BiOBr (named BO<sub>v</sub>B) through an in situ surface reconstruction progress, in which the CO<sub>3</sub><sup>2−</sup> in solution reacted with the generated Bi<sup>(3−x)+</sup> around the oxygen vacancies. The in situ formed BO<sub>v</sub>C is tightly in contact with the BO<sub>v</sub>B and can prevent the further destruction of the oxygen vacancy sites essential for CO<sub>2</sub> adsorption and visible light utilization. Additionally, the superficial BO<sub>v</sub>C associated with the internal BO<sub>v</sub>B forms a typical heterojunction promoting the interface carriers’ separation. Finally, the in situ formation of BO<sub>v</sub>C boosted the BOvB and showed better activity in the photocatalytic reduction of CO<sub>2</sub> into CO (three times compared to that of pristine BiOBr). This work provides a comprehensive solution for governing defects chemistry and heterojunction design, as well as gives an in-depth understanding of the function of vacancies in CO<sub>2</sub> reduction.
|
|---|