Gas-Phase Photocatalytic Oxidation of Benzene over TiO2 Supported on Ce0.5-xZr0.5-xBa2xO2

Abstract Photooxidation of gaseous benzene was investigated using anatase TiO 2 as the catalyst in a closed steel reactor. The photocatalytic activity can be greatly improved by supporting TiO 2 on Ce 0.5- x Zr 0.5- x Ba 2 x O 2 . The optimal Ba content in the photocatalyst was investigated. The prepared photocatalysts were characterized by X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The results revealed that the deposited titania is well dispersed as in the Ce 0.5- x Zr 0.5- x Ba 2 x O 2 matrix. TiO 2 /Ce 0.5- x Zr 0.5- x Ba 2 x O 2 absorbs much more ultraviolet light in the range of 210–400 nm than TiO 2 . There are Ti and O elements on the surface of TiO 2 /Ce 0.5- x Zr 0.5- x Ba 2 x O 2 , and the binding energy of Ti 2 p of TiO 2 /Ce 0.5- x Zr 0.5- x Ba 2 x O 2 shifts to a lower value. Based upon these observations, it is concluded that the role of Ce 0.5- x Zr 0.5- x Ba 2 x O 2 is to transfer electrons and enhance the light absorption of the catalyst in the region of 210–400 nm.