W and Mo doped TiO2: Synthesis, characterization and photocatalytic activity

Abstract

W-doped TiO2 and Mo-doped TiO2 photocatalysts were synthesized by EISA method and were characterized by different techniques. The photoactivity of these materials was evaluated by the degradation of 4- chlorophenol without oxygen supply. The catalysts exhibited only anatase crystalline phase and high specific surface areas of about 179 m2 g 1. The amount of dopant cations in TiO2 was a key parameter to increase the photoactivity. The results obtained show that with low dopant concentrations the degradation is improved, and this can be attributed to an increase in the lifetime of the photogenerated charges due to that dopant cations may easily trap electrons decreasing the recombination rate. Doped photocatalysts degraded 95% of 4CP, three times faster than Degussa P25. 69% reduction of total organic carbon (TOC) content was achieved by 1 wt.% W-doping.