Construction of hole‐transported MoO3‐x coupled with CdS nanospheres for boosting photocatalytic performance via oxygen‐defects‐mediated Z‐scheme charge transfer

The establishment of Z‐scheme charge transfer between semiconductors is an effective method to improve the performance of hybridized semiconductor photocatalysts. Herein, the novel photocatalysts consisting of MoO_3‐x and varying amounts of cadmium sulfide (CdS) nanospheres were successfully prepared via the one‐pot hydrothermal method in the presence of polyvinylpyrrolidone (PVP). It is indicated that the PVP not only served as the reducing agent for the formation of oxygen defects in MoO_3‐x, but also the cross‐linking agent for the coupling between MoO_3‐x and CdS. The CdS/MoO_3‐x composite allowed for higher visible‐light photocatalytic performance for enhanced removal of methylene blue and tetracycline with an efficiency of 97.6% and 85.5%, respectively. The improved performance of the CdS/MoO_3‐x composite was found to be mainly attributable to the remarkable charge carrier separation and transfer between CdS and MoO_3‐x based on the favorable hole‐transporting nature and oxygen deficiencies of MoO_3‐x. In addition, the hole‐oxidized photocorrosion of CdS was efficiently suppressed due to the presence of hole‐attractive MoO_3‐x. At the solid interface, an oxygen‐defects‐mediated Z‐scheme charge carrier transfer pathway was proposed as the underlying mechanism for the superior photocatalytic reaction.