Abstract
It is an efficient strategy to extend the light response range of TiO2-based photocatalysts to visible light region by constructing heterojunctions with the low bandgap semiconductors. The bandgap edge match between the low bandgap semiconductors and the TiO2 substrate is believed to a key to sensitize the TiO2-based photocatalysts. In this study, TiO2 (anatase) nanofibers were modified by ZnFe2O4 nanoparticles from ZnO colloid. The ZnFe2O4 nanoparticles with a relatively narrow band gap of 1.90 eV and the conduction band edge at -1.54 eV (vs NHE) which is more negative than that of TiO2. So as expected, the ZnFe2O4 particles extended the photoresponse of TiO2 (anatase) nanofibers into the visible light region and enhanced the photoresponse of UV light. The photogenerated electron hole separation in ZnFe2O4/TiO2 (anatase) composite nanofibers is responsible for the rapidly increased photocurrent under the visible light and UV light irradiation.