Abstract：Diatomite-TiO₂ composite materials were synthesized by the in-situ hydrolysis-condensation reaction between tetrabutyl titanate (TBOT) and porous diatomite in an ammonia atmosphere.The morphology, composition and catalyst efficiency of the composite materials were characterized by scanning electron microscopy (SEM) , X-ray diffraction (XRD) , energy dispersive X-ray spectroscopy (EDS) and UV spectrophotometer, respectively. Meanwhile, the methyl orange was catalyzed by the diatomite-TiO₂ composite materials. The results indicate that the nano-sized TiO₂ particles are generated in-situ on the surface and inner pores of the diatomite by the hydrolysis and condensation of TBOT under aqueous vapor. The prepared material maintains bimodally texture of porous diatomite and nano-spherical TiO₂.The experiment of the degradation of the methyl orange proves that the composite materials possess photocatalytic performance.

Keywords: diatomite; titanium dioxide; gas phase sol-gel method; photocatalysis