Synthesis and photocatalytic property of a mixture of anatase and rutile TiO2doped with Fe by mechanical alloying process

The nanocrystalline Fe-doped mixture TiO2 Powders which consisted of anatase and rutile phase were synthesized by mechanical alloying (MA). The mixtures TiO2 powders had small particle size in the range of 10-15 nm with spherical shape. Photocatalytic property of a mixture of anatase and rutile TiO2 doped with Fe was investigated. In the PL and UV-DRS data, Fe-doped mixture TiO2 showed the photo-absorption threshold shifted to the high wavelength (442 nm; 2.81 eV), suggesting a decrease in the band gap, and the decreased intensity of PL indicating the decrease of recombination of E-H pairs (e(-) and h(+)). In the decomposition of 4-chlorophenol, the Fe 2 wt% doped mixture TiO2 powder bad the highest decomposition rate as compared to P-25, pure anatase and pure rutile powders. The band gap of Fe-doping TiO2 powder was decreased because of trapping level near the valance band or conduction band. The recombination of generated E-H pairs of mixture TiO2 powder was decreased due to the difference in Fermi levels of anatase and rutile. (c) 2007 Published by Elsevier B.V.