TiO_2/SiO_2复合粉体的制备及催化性能的研究

Study on the preparation of TiO_2/SiO_2 composite powder and its photocatalytic activity

文章采用XRD和FT-IR等方法对用Sol-Gel法制备的TiO2/SiO2复合粉体进行了表征,考察了原料组成和焙烧温度对复合物相变温度和晶型转变的影响,以及掺杂对甲基橙光催化降解的影响。研究表明,TiO2微粒以锐钛矿相高度分散在SiO2基质中,并与其形成了Ti-O-Si桥氧结构,提高了TiO2的表面积和表面缺陷,有利于有机物的吸附及半导体光生电子-空穴的分离,从而提高了半导体的光催化活性。

The TiO2/SiO2 composite powder made by the sol-gel technique was analyzed by means of XRD and FT-IR. The effects of composition and heat treatment on the transformation temperature of the anatase phase into the rutile phase as well as the effect of doping of SiO2 on the photocatalytic degradation of methyl orange were examined. The investigation indicate that titanium dioxide particles were highly dispersed and the Ti-O-Si tetrahedral network was formed in the TiO2/SiO2 complex particles. The catalyst has a large specific surface area and high photocatalytic reactivity due to more effective separation of electrons and holes, resulting in enhanced degradation of methyl orange.