Hydrothermal preparation, characterization and photocatalytic activity of TiO2/Fe–TiO2 composite catalysts

Highly active TiO2/Fe–TiO2 composite photocatalysts with a p–n heterojunction structure have been prepared by mixing hydrothermal-derived TiO2 and Fe–TiO2 nano-powders followed by grinding and drying. These photocatalysts were characterized by XPS, XRD, TEM, BET, UV–vis and Fluorescence spectroscopy, and their photocatalytic activities were evaluated by the decolorization rate of methyl orange under UV irradiation. TiO2/Fe–TiO2 composite photocatalysts were generally shown to have a much higher photocatalytic destruction rate than pure TiO2, mainly due to electrostatic-field-driven electron–hole separation in TiO2/Fe–TiO2 composites. The best TiO2/Fe–TiO2 composite photocatalyst with mass ratio TiO2:0.5 at%Fe–TiO2 of 12:1 showed approximately 3.8 times higher photocatalytic activity than undoped TiO2.