【摘要】 TiO2 -SiO2 复合半导体气凝胶是一种新型纳米光催化氧化剂。本文以正硅酸乙酯、钛酸丁酯为原料 ,用溶胶—凝胶法经超临界干燥制备出了TiO2 -SiO2 复合半导体气凝胶。研究了TiO2 :SiO2 不同配比对溶胶—凝胶过程的影响 ;用BET、XRD、SEM、TEM等测试方法对其结构进行了表征 ;以苯酚为探针考察了TiO2 -SiO2 复合半导体气凝胶的光催化氧化活性 ,并与普通锐钛矿型钛白粉光催化剂进行了对比。结果表明 :所制备的TiO2 -SiO2 复合半导体气凝胶具有大比表面积 ( 5 2 3.8m2 g-1) ,纳米多孔结构 (骨架颗粒约为 30 - 5 0纳米 ,孔洞尺寸为几十纳米 ) ;其光催化氧化活性大大高于普通锐钛矿型二氧化钛更多还原

【Abstract】 Nano-porous photocatalyst TiO 2-SiO 2 binary semiconductor aerogels were prepared by the sol-gel method with Ti(OC 4H 9) 4 and Si(OC 2H 5) 4 as the precursors and by supercritical drying of ethanol. The influence of ethanol, water and the mole ratio of TiO 2 and SiO 2 on the gelation process was investigated. The microstructure of the TiO 2-SiO 2 binary semiconductor aerogel was also tested by using BET、XRD、SEM . The photocatalytic activity of TiO 2-SiO 2 binary semiconductor aerogels was characterized by measuring degradation of phoenol in aqueous suspension. The results showed that the TiO 2-SiO 2 binary aerogels had high surface area(523.8m 2g -1 )and the diameter of their skeletal particles is 30-50 nm. Compared with titania powder(in the form of anatase and particle diameter 3-5μm), it was proved that the TiO 2-SiO 2 binary semiconductor aerogel with TiO 2:SiO 2 mole ratio 1:1 had the highest efficiency in the photocatalytic oxidation of phenol under the same experimental conditions.更多还原