Preparation of nano TiO_2 film modified with phosphatotungstic acid and photocatalytic performance

The nano TiO_2 film modified with phosphatotungstic acid(PW12/TiO_2)was prepared by sol-gel method using tetrabutyl titanate(TBOT) as a precursor and acetic acid as solvent,and was characterized by FTIR,UV-Vis,XRD,BET and SEM.The result indicates that the TiO_2 nanoparticles has the anatase structure and high specific surface.Phosphatotungstic acid still keeps Keggin structure in TiO_2 and inhibites the growth of crystal grain.The photocatalysis degradation of p-chlorophnol with PW12/TiO_2 film was investigated to study the catalytic activities of the film.The result indicated that photocatalysis reaction accorded to L-H mechanism with PW12/TiO_2 film(the ratio of phosphatotungstic acid and titania was 0.02∶1,calcinated at 240℃),First-order reaction rate constant was 0.016min-1.There produced obvious synergy between PW12 and TiO_2 in photocatalysis reaction.