以硫酸钛为前驱体的简单溶胶-凝胶法合成纳米多孔二氧化钛粉末

 以无机硫酸钛溶液为前驱体,甲酰胺为pH值调节剂,本文采用简单溶胶-凝胶法合成纳米多孔的TiO₂粉末。运用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)和氮吸附脱附(N₂ Adsorption/Desorption)等方法对合成的TiO₂粉末进行了表征。结果表明,合成的TiO₂粉末具有高的热稳定性,450—750℃的温度范围内焙烧后为单一的锐钛矿相结构,且850℃焙烧后主要相为锐钛矿相。随着焙烧温度的升高,TiO₂粉末的晶粒长大,比表面积减少。550℃焙烧后的TiO₂粉末是由平均晶粒尺寸约为10nm的颗粒聚集而成,其比表面积约为219.70m²·g^-1,并且具有独特的双孔结构。

Simple Sol-Gel Route for Preparation of Nanosized Porous TiO2 Powders Using Inorganic Precursor

NThe nanosized porous TiO₂ powders were synthesized by using the titanium sulfate solution through a simple sol-gel route, where the formamide was used as the pH adjusting agent. The X-ray diffraction, the scanning electron microscopy, the transmission electron microscopy and the N₂ Adsorption/Desorption were used to analyze the prepared samples. The results show that the prepared TiO₂ powders have a high thermal stability and maintain as a monophasic anatase in cases of calcination from 450℃ to 750℃, furthermore, the main crystalline phase remains as that of anatase even at 850℃. The crystalline grains of TiO₂ powders grow larger and the specific surface area is reduced with enhancing the calcination temperature. The microstructure of TiO₂ powders is that of aggregation of nanocrystalline with diameter of approximately 10 nm in case of calcination at 550℃. The specific surface area of the prepared samples is approximately 219.70m²·g^-1 after calcinating at 550℃ and there is a specific bimodal pore structure in the prepared samples.