Fabrication of Ag/ZnO hollow nanospheres and cubic TiO2/ZnO heterojunction photocatalysts for RhB degradation

ZnO nanomaterials with the stereochemical structure were becoming a research focus in the scope of photocatalytic materials, but the ZnO was sensitive to UV light rather than the solar light source, which considerably prohibited its extended application. ZnO nanomaterials coupled with other nanomaterials could generate the alternative composite heterojunction nanomaterials to promote the photocatalytic activity. Herein, we reported two facile and feasible synthesis methods to fabricate TiO2/ZnO cube nanocomposites and Ag/ZnO hollow spheres by hydrothermal reaction and chemical deposition, respectively. In this regard, these composited nanomaterials have been successfully fabricated with high purities, good morphology, and crystal structure. Noticeably, in contrast with TiO2/ZnO and Ag/ZnO bulk nanocomposites, the Ag/ZnO hollow spheres could offer the higher activity for RhB degradation under the visible light. Moreover, the photocatalytic performance of Ag/ZnO for RhB degradation could be improved synergistically, and the effect of RhB degradation was highest when the Ag mass ratio was modulated at 10% in the sample. Furthermore, it remained a high photocatalytic efficiency even after four cycles. This protocol provided an approvable approach to fabricate efficient photocatalysts with persistent photostability in the wastewater treatment process.