Enhanced photocatalytic efficiency of ZnO/ZnSe coaxial nanowires through interfacial strain modification

Two kinds of ZnO/ZnSe coaxial nanowires were successfully fabricated by a two-step chemical vapor deposition method, and their applications for photocatalytic degradation were investigated. Morphology studies demonstrated that the structures of ZnO nanowires could be controlled through the growth process, and single-diameter and dual-diameter ZnO/ZnSe coaxial nanowires were successfully synthesized. It is found that compared with the single-diameter coaxial nanowires, the dual-diameter coaxial nanowires bear the larger tensile strain and possess the higher ratio of coherent layer due to the thinner ZnO core; meanwhile, they have the stronger light absorption in the whole visible region because of the light trapping effect and the interfacial transition. Finally, a 1.3-fold enhancement of photocatalytic performance was achieved for the dual-diameter coaxial nanowires, and the possible enhanced mechanism was discussed. This work provides an efficient strategy to improve photocatalytic performance of nanomaterials through interfacial strain modification.