LIU Cong, HAN Song,WANG Kun, HAN Song
(School of forestry, Northeast Forestry University, Harbin150040, Heilongjiang, China )
Abstract: Using tetrabutyl titanate, ethyl orthosilicate, acetic acid, anhydrous ethanol and other reagents as raw materials, the thesis respectively adopte hydrothermal method and solvethermal method to produce the composite photocatalyst of nano SiO2/TiO2 composite photocatalyst. Through Characterization analysis of SEM, XRD, BET, etc, we explore the phase composition and microstructure and then measure the catalytic degradation ability of the achieved composite photocatalyst effecting on The light of methylene blue under the condition of xenon lamp irradiation. By this method, the thesis explore the influence of different molar ratio of Si and Ti in composite photocatalyst on photocatalytic activity. The result show that adopting anhydrous ethanol as solvent, composite photocatalyst that produced on the condition of the molar ratio of Si and Ti being 1:1 has large specific surface area, which is 387.9634 m2 / g, and the distribution of the pores are moderate.Under the condition of room temperature, when the reaction lasts 2 h,the degredation rate of methylene blue reaches over 99%,which is better than that of P25 nano TiO2 Photocatalyst. The catalytic activity is the best when the molar ratio of Si and Ti comes to 1:1.The catalytic activity of the photocatalyst synthesized via solvethermal method is better than that of hydrotnermal method.The degradation ability of composite photocatalyst is closely related to the composition of the samples, synthesis conditions as well as the size of particle.
Key words: SiO2/TiO2; hydrothermal; solvethermal;methylene blue; photocatalytic degradation