介孔二氧化钛的非有机模板剂法合成

Synthesis of Mesoporous Titanium Dioxide without Using Organic Templates

采用硫酸钛水解法在不使用有机模板剂的条件下合成了高热稳定的锐钛矿型介孔TiO2.以工业硫酸钛溶液为原料,经两步水解得到介孔结构的偏钛酸,500℃下焙烧后得到比表面积为202·2m2/g、平均孔径为2·8nm并具有超强酸特性的介孔TiO2.使用X射线衍射、N2吸附、扫描电镜、X射线能谱和红外光谱对该样品进行了表征,初步讨论了介孔的形成机理.吸附在偏钛酸孔壁上的硫酸分子和孔壁上的自由羟基键合,起到了孔结构的导向作用及支撑作用.

Thermally stable mesoporous anatase TiO2 was prepared in the absence of organic templates via two step hydrolysis of industrial titanyl sulfate solution to form mesoporous metatitanic acid followed by calcination at 500 C for 2 h. The me,porous TiO2 obtained has a surface area of 202.2 m^2/g and an average pore diameter of 2.8 nm. TiO2 contains SO4^2- and shows superacid properties. The mesoporous material was characterized by various methods and the mechanism of formation of the mesoporous structure was discussed. Sulfuric acid adsorbed on pore walls of the mesoporous metatitanic acid is bonded to the free hydroxyl groups on the pore walls, which acts as a structural directing agent and pore structure support.