Coaxial Nanofibers of ZnO-TiO2 Heterojunction With High Photocatalytic Activity by Electrospinning Technique

Abstract

The ZnO-TiO2 coaxial nanofibers with high photocatalytic activity using ZnO as the core and TiO2 as the shell were successfully fabricated by a simple combined method of sol-gel process and electrospinning technique, which were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and so on. The results showed that the ZnO-TiO2 coaxial nanofibers consisted of hexagonal wurtzite ZnO core and TiO2 shell of anatase and rutile. Comparing with the ZnO nanofibers and TiO2 nanofibers, UV-vis absorption peaks of ZnO-TiO2 coaxial nanofibers showed a significant red-shift, which revealed that ZnO-TiO2 nanofibers needed less energy to be activated. The ZnO-TiO2 coaxial nanofibers exhibited better photocatalytic activity for the degradation of methylene blue than TiO2, ZnO, or blending ZnO-TiO2 nanofibers. Besides, the ZnO-TiO2 coaxial nanofibers could be easily recycled.