Preparation and characterization of S-doped TiO 2 nanoparticles, effect of calcination temperature and evaluation of photocatalytic activity

Abstract

S-doped TiO 2 photocatalyst with high activity of visible light was prepared by modified sol–gel method using thiourea as sulfur source. The catalyst was characterized by XRD, FT-IR, DRS, SEM-EDX and TEM analysis. The undoped and S-doped TiO 2 nanoparticles calcined at 500 °C contained only anatase phase. Effects of calcination temperature showed formation of rutile phase get started at 650–700 °C for undoped TiO 2 and 750 °C for S-doped TiO 2. The activity of the catalyst was examined by photodegradation of methyl orange in aqueous solution under both visible and UV light and it was found to be depending on the amount of S. The most activity was observed for 0.05% and 0.1% S-doped TiO 2 under visible and UV light, respectively. Results showed for undoped TiO 2, calcined samples at 650 and 550 °C under visible and UV light are the best catalysts, respectively. Also for 0.05% S-doped TiO 2, calcined sample at 500 °C is the best catalyst under UV and visible light.