关键词: 纳米SiO2/ TiO2, 光催化, 微乳液, 水热

Abstract: A SiO2/TiO2 composite photocatalyst was prepared by microemulsion method using inorganic polymerized silicate as the silicon source and titanium sulfate as the titanium source. The influence of preparation conditions on photocatalytic activity was investigated，and the photocatalyst was characterized by SEM，FTIR，XRD and BET. The results prove that a strong interaction exists between SiO2 and TiO2 particles，the formation of Ti—O—Si bond inhibits the TiO2 particle growth and also defers the transformation of TiO2 from anatast to rutile phase. The photocatalytic degradation of dyes，such as methyl orange，shows that the photocatalytic activity of SiO2/TiO2 is not improved along with higher propotion of TiO2. when the amount of substance ratio between Silicon and Titanium was 1∶1，and the photocatalyst was hydrothermal synthesized for 2.5 h at 160 ℃，the decoloration rate of methyl orange under UV light irradiation for 15 minutes over the SiO2/TiO2 photocatalyst could reach 85.5%，which has better photocatalytic activity and higher specific surface area than the TiO2 photocatalyst prepared under the same condition.

Key words: nanosized SiO2/ TiO2, photocatalysis, microemulsion, hydrothermal