Photocatalytic degradation of methylene blue by visible-light-driven yttrium-doped mesoporous titania coated magnetite photocatalyst

ABSTRACT

A novel kind of visible-light-driven photocatalyst (Y/MTiO₂/Fe₃O₄) with yttrium-doped mesoporous titania (Y/MTiO₂) shell and a magnetite core was prepared by coating photoactive Y/MTiO₂ onto a magnetic Fe₃O₄ core through the hydrolysis of tetrabutyltitanate (Ti(OBu)₄) with precursors of Y(NO₃)₃·6H₂O and (Ti(OBu)₄) in the presence of Fe₃O₄ particles, the MTiO₂ shell was for photocatalysis, the Fe₃O₄ core was for separation by the magnetic field and the doped Y was used to enhance the photocatalytic activity of MTiO₂. The photocatalytic activities of obtained photocatalysts under visible light were estimated by measuring the degradation rate of methylene blue (50 mg/L) in an aqueous solution. The results showed that the prepared photocatalyst was activated by visible light and used as effective catalyst in photooxidation reactions. In addition, the possibility of cyclic usage of the prepared photocatalyst was also confirmed. Moreover, the photocatalyst could be easily recovered from the medium by an external magnetic field and be reused without any mass loss. It can therefore be potentially applied for the treatment of water contaminated by organic pollutants.

Keywords:

• Mesoporous titania
• Magnetite
• Yttrium-doping
• Photocatalytic degradation
• Methylene blue

Acknowledgment

The authors gratefully acknowledge financial support for this work from the National Natural Science Foundation of China (41173119).