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

In this study, a three dimensional (3D) MoS2/-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 -Bi2O3 spheres. Compared with pure -Bi2O3 microspheres, the 1.0% MoS2/-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 30min, respectively. The enhanced photocatalytic activity is attributed to the formation heterojunction between MoS2 quantum dots and -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 O-2(-.) and h(+) are the reactive species for BPA degradation. The recyclability test confirms that the 1.0% MoS2/-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.