Pretreatment of the photocatalyst and the photocatalytic degradation of trichloroethylene in the gas-phase

Pretreatment effect of the photocatalyst on the gas-phase degradation reaction of trichloroethylene (TCE) was studied over the TiO2 sol-gel films and powder. Photocatalytic degradation reaction of TCE depended greatly on the pretreatment method of photocatalyst. Among pretreatments tested, UV preillumination on the photocatalyst before the reaction was the most effective method to increase the degradation rate of TCE. These results indicated that the adsorbed species such as water molecule on the photocatalyst surface made the reaction proceed slowly. Diffuse reflectance infrared Fourier transform (DRIFT) measurement revealed that OH group and water molecule adsorbed on the TiO2 surface were removed by UV illumination.