Understanding oxygen vacant hollow structure CeO 2 @In 2 O 3 heterojunction to promote CO 2 reduction

Abstract In order to reduce the impact of greenhouse gases, we have studied a new and efficient photocatalyst to reduce CO 2 . We recombined the hollow CeO 2 with the In 2 O 3 and introduced the oxygen vacancy to obtain the CeO 2 @In 2 O 3 for the hollow structure of the oxygen vacancy. The test results show that CeO 2 @In 2 O 3 with oxygen vacancy hollow structure (hereinafter collectively referred to as H‐CeO 2 , H‐In 2 O 3 , and H‐CeO 2– x @In 2 O 3– x ) have higher photocatalytic reduction activity of CO 2 than hollow CeO 2 and hollow In 2 O 3 . When the illumination time was 4 h, the yields of carbon dioxide reduction to CO and methane were 38.7 and 7.8 μmol·g −1 , respectively. Consequently, we explained the photocatalytic reduction mechanism, and carried out the X‐ray diffraction (XRD) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis of H‐CeO 2 , H‐In 2 O 3 , and H‐CeO 2– x @In 2 O 3– x . This study summarizes some experience for the study of oxygen vacancy hollow structure photocatalyst, and provides some new ideas in the field of photocatalytic reduction of CO 2 .