Enhanced photovoltaic effect of TiO2-based composite ZnFe2O4/TiO2

A TiO 2 -based composite, ZnFe 2 O 4 /TiO 2 , was prepared with a commercial TiO 2 (Degussa P25) and ZnFe 2 O 4 nanopowders using a simple method. The composite was characterized by X-ray diffraction (XRD), UV–vis absorption spectrum, surface photovoltage spectroscopy (SPS) and SEM. The composite presents an enhanced photovoltaic effect compared with the pure TiO 2 . The trap distributions of TiO 2 and ZnFe 2 O 4 /TiO 2 composite were investigated and the energy levels of TiO 2 and ZnFe 2 O 4 were analyzed. The results indicate that the enhancement of photovoltaic effect is mainly due to the increase of photo-generated carrier concentration and improvement of the separation efficiency of photo-generated carriers by the addition of ZnFe 2 O 4 .