Novel Z-scheme Cu2O-UNPs/ZnO SCNRs heterojunction with enhanced photocatalytic performance for organic dyes

Photocatalysis is considered as a promising method to control water pollution caused by organic and biological pollutants. However, this technology faces some challenges, especially the easy recombination of photogenerated electron hole pairs. The construction of p–n heterojunction is a feasible way to expand the light absorption range and inhibit charge carrier recombination to improve the photocatalytic performance. But p–n heterojunction is at the expense of semiconductor redox ability to some extent. So it is necessary to build a new model to solve the above problems. Herein, an emerging Z-scheme photocatalyst composed of ZnO single crystal nanorods (SCNRs) assisted Cu 2 O ultrafine nanoparticles (Cu 2 O-UNPs) is successfully synthesized using a hydrothermal method in conjunction with a chemical reduction. The two parts of this heterostructure are chemically bonded one another to form a tight interface. The specific surface area of Cu 2 O/ZnO is 28.6 time than that of pure ZnO. The Cu 2 O/ZnO exhibited excellent photocatalytic activity and stability on simultaneous organic dye degradation due to the high redox ability. The addition of Cu 2 O can inhibit the photogenerated electron–hole pair recombination, facilitate an effective interface charge transfer, and increase the activity of photocatalysis. Under UV–visible light, this heterojunction displayed impressive ability to degrade for anionic and cationic organic dyes. ⋅OH active species play a major role in the photocatalytic process. Therefore, based on the relevant characterization results, a reasonable photocatalytic mechanism based on Z-scheme heterostructure was established. Moreover, this novel Cu 2 O-UNPs/ZnO SCNRs Z-scheme heterojunction also presents an extraordinary chance for use in waste disposal and purification.