锐钛矿型纳米TiO2介孔粉体表面织构的研究

以硫酸钛和尿素为原料,聚乙二醇-1000为空间构造剂,104℃下经尿素水解均匀沉淀法研制颗粒分散均匀、粒径可控的高热稳定性锐钛矿型纳米TiO2介孔粉体,并对其晶相、颗粒大小、比表面积、形貌和孔道结构进行了表征.结果表明,未经任何热处理的TiO2粉体即为锐钛型晶相,颗粒为均匀分散的类球型颗粒,且颗粒间形成直通型的介孔孔道,其孔径在10～30nm之间.控制焙烧温度可以达到控制颗粒大小及形貌的目的,经850℃焙烧5h的样品仍保持锐钛矿型晶相,未出现向金红石型晶相转变的迹象.

Surface Texture of Nanometer Mesoporous Titania Powders

Nanometer titania mesoporous powders were prepared by heating the mixed solution of titanium disulfate and polyethylene glycol(PEG-1000) in the presence of urea under hydrothermal conditions at 104 ℃.The texture, morphology and crystallite size of the synthesized nanoparticle powders were investigated by XRD, BET, TEM and DSC. The powders dried at room temperature and calcined at temperature below 850 ℃, their particles were spherical, well dispersed, ultrafine titania, with anatase phase. Their crystallite size increased from 8.56 to 48.82 nm with increasing the calcining temperature from room temperature to 850 ℃.The pore structure among particles, open-ended tubular pores, were mesoporous texture, the average pore diameters were from 10.36 to 27.25 nm.