Preparation of magnetically supported chromium and sulfur co-doped TiO2 and use for photocatalysis under visible light

Novel magnetic chromium and sulfur co-doped TiO2 photocatalysts (M-Cr/S/TiO2) have been prepared by a sol-gel process, using magnetic hollow fly ash microspheres as support material. The crystal phase of M-Cr/S/TiO2 was characterized by X-ray diffraction, UV-visible absorption spectroscopy, and transmission electron microscopy. The photocatalytic activity of the photocatalysts was examined by photodegradation of methyl orange in aqueous solution under visible light irradiation. The results showed that chromium and sulfur co-doped catalysts (Cr/S/TiO2) containing 0.60 % (atomic ratio) chromium and 1.2 % (atomic ratio) sulfur calcined at 450 A degrees C for 2 h had high catalytic efficiency under visible irradiation. It is worth mentioning that the floating M-Cr/S/TiO2 catalyst had greater photocatalytic activity than Cr/S/TiO2 powder. Therefore, M-Cr/S/TiO2 is a promising, high-performing, visible-light-driven photocatalyst.