Low temperature preparation and visible light induced photocatalytic activity of europium doped hydrophobic anatase TiO2-SiO2 photocatalysts.

The Eu(3+) doped TiO2-SiO2 photocatalysts, as a reclaimed visible-light responsive photocatalyst, were prepared by sol-gel method with TEOS, TBT and europium nitrate as precursors, by keeping the molar of TEOS:TBT constant at 1:1 and with different europium doping content. The resulting photocatalysts were characterized by XRD, TEM, SEM, EDX, UV-VIS DRS, FTIR and BET method. Analytical results demonstrated that only anatase phase is present in photocatalysts with high surface areas. The mean size is around 10 nm form TEM, which is consistent with the analytical result according to SEM. It can be seen methyl groups exist in photocatalysts based on analysis of FTIR and EDX. It was found that the resulting Eu(3+) doped photocatalysts exhibit higher photocatalytic activity than undoped photocatalysts and P25 on the degradation of rhodamine B(RhB, 10 mg/l) in water under visible light irradiation (lambda > 410). After irradiation for 3 h, the maximum absorption decreases gradually with irradiation time and absorption band shifts from 554 to 507 nm.