The carbon quantum dots modified ZnO/TiO2 nanotube heterojunction and its visible light photocatalysis enhancement

The carbon quantum dots modified ZnO/TiO2 nanotube heterojunction is synthesized via simple electrospinning-hydrothermal method. The results of SEM, XRD, TEM, FT-IR and XPS imply that the C QDs and ZnO nanoparticles have deposited on the surfaces of the TiO2 nanotubes successfully. Compared with the unmodified samples, the photocatalytic performance of the as-prepared C QDs modified ZnO/TiO2 nanotube heterojunction exhibits a remarkable enhancement by the degradation of Rhodamine B (RhB) under the visible light. Further, the up-conversion fluorescence of the C QDs, the heterojunction of the ZnO/TiO2 and the tubular structure of the TiO2 are considered as the main reasons for the enhancement.