Various TiO2 microcrystals: Controlled synthesis and enhanced photocatalytic activities

Titania microspheres with higher photocatalytic activity have been synthesized using TiCl4 and FeCl3 as the precursor in the presence of Span-80. The products were characterized with XRD, TEM and UV–vis DRS. XRD and TEM indicated that the microsphere was a mixture of rutile, brookite and anatase with a diameter of about 5–7 μm. The photocatalytic experiments revealed that the microspheres exhibited high photocatalytic activities under UV-light and solar irradiation. The degradation rate of methyl orange (MO) was 100% under UV-light irradiation for 3 h and 91% under solar irradiation for 6 h. In particular, the catalysts could be readily separated by sedimentation after the photocatalytic reaction.