Abstract: Photooxidation of gaseous benzene was investigated using anatase TiO2 as the catalyst in a closed steel reactor. The photocatalytic activity can be greatly improved by supporting TiO2 on Ce0.5-xZr0.5-xBa2xO2. The optimal Ba content in the photocatalyst was investigated. The prepared photocatalysts were characterized byX-raydiffraction, UV-Vis diffuse reflectance spectroscopy, andX-rayphotoelectron spectroscopy. The results revealed that the deposited titania is well dispersed as in the Ce0.5-xZr0.5-xBa2xO2 matrix. TiO2/Ce0.5-xZr0.5-x-Ba2xO2 absorbs much more ultraviolet light in the range of 210-400 nm than TiO2. There are Ti and O elements on the surface of TiO2/Ce0.5-xZr0.5-xBa2xO2, and the binding energy of Ti 2p of TiO2/Ce0.5-xZr0.5-xBa2xO2 shifts to a lower value. Based upon the above observations, it is concluded that the role of Ce0.5-xZr0.5-xBa2xO2 is to transfer electrons and enhance the light absorption of the catalyst in the region of 210-400 nm.

Key words: titanium dioxide, photocatalytic oxidation, benzene, ceria-zirconia solid solution, volatile organic compound