Sonochemical Fabrication of s-Scheme Hierarchical CdS/BiOBr Heterojunction Photocatalyst with High Performance for Carbon Dioxide Reduction

CO2 conversion to methanol becomes a promising strategy by using semiconductor-based photocatalyst for environmental remediation and converting solar energy. In this study, a series of CdS-modified BiOBr (CdS/BiOBr) microspheres are fabricated by mild hydrolysis-ultrasonic method and the effect of CdS growing on the photocatalytic CO2 reduction activities of BiOBr are systematically investigated. Among all CdS/BiOBr composite photocatalysis, the highest value of CH3OH yields (876 mu mol g(cat)(-1), 4 h) is achieved with 15% CdS/BiOBr, which is nearly double higher than alone BiOBr (435 mu mol g(cat)(-1)). Comparatively, the CdS/BiOBr microspheres with s-scheme heterostructure exhibit the surprising photocatalytic performance and CH3OH selectivity, which are attributed to the enhanced light absorption, as well as effective separation and migration of the photoinduced electron-hole pairs induced by the s-scheme heterojunction between BiOBr and CdS. This study provides a mild hydrolysis-ultrasonic method for environmental remediation and converting energy using cost-effective semiconductor materials.