MoS2 quantum dots-modified porous β-Bi2O3 microspheres with enhanced visible-light-induced photocatalytic activity for Bisphenol A degradation and NO removal

Abstract

In this study, a three dimensional (3D) MoS2/β-Bi2O3 heterostructure with high-performance for photocatalytic removal of pollutants was constructed by a simple deposition of the MoS2 quantum dots on the surface of porous β-Bi2O3 spheres. Compared with pure β-Bi2O3 microspheres, the 1.0% MoS2/β-Bi2O3 composite exhibited excellent photocatalytic activity in the degradation of Bisphenol A (BPA) in aqueous solution and oxidative removal of gaseous NO under visible light irradiation, and the removal efficiency reached 94.0% and 41.4% for BPA and NO within 30 min, respectively. The enhanced photocatalytic activity is attributed to the formation heterojunction between MoS2 quantum dots and β-Bi2O3, which facilitates the separation and transfer efficiency of photogenerated electron–hole pairs, boosts catalytic active sites and hinders an electron–hole recombination rate. The results of trapping experiments indicates that both of O2−∙ and h+ are the reactive species for BPA degradation. The recyclability test confirms that the 1.0% MoS2/β-Bi2O3 composite photocatalyst has a superior stability during recycling cycle. This work demonstrates that a unique 3D photocatalyst system can provides a new perspective and opens up new opportunities on the design of efficient composite photocatalysts.