纳米TiO2介孔薄膜的模板组装制备研究

以TiCl₄为无机前驱体、三嵌段高分子共聚物EO₂₀PO₇₀EO₂₀为模板剂，在非水条件下制备了有序的锐钛矿TiO₂纳米晶介孔薄膜。通过热重-差热（TG-DTA）分析、X射线衍射（XRD）分析、原子力显微观察（AFM）及N₂吸附-脱附等测试对样品进行了表征。结果表明，薄膜具有均一的大介孔孔径（～10 nm），其BET比表面积为150 m²·g^-1，薄膜较宽的无机壁厚显著提高了介孔结构的热稳定性。通过红外（IR）光谱分析考察了溶胶-凝胶过程中发生的物理化学变化。在对薄膜表面形貌进行AFM观察的基础上初步探讨了嵌段共聚物EO₂₀PO₇₀EO₂₀对薄膜孔结构形成的导向机理。

Preparation of Nanocrystalline Titania Mesoporous Films by Template Assembled Method

Organized mesoporous thin films of nanotextured anatase were prepared by hydrolysis of TiCl₄ in the presence of poly(alkylene oxide) block copolymer EO₂₀PO₇₀EO₂₀, acting as templates under non-aqueous conditions. The samples were characterized by thermogravimetry-differential thermal analysis(TG-DTA), X-ray diffraction(XRD), atomic force microscopy(AFM) and N₂ adsorption-desorption isotherm. The results show that the pores are uniform with large mesoporous diameter about 10 nm and BET specific surface area of the film is 150 m²·g^-1. The thick inorganic wall significantly enhances the stability of the porous structure. The physical and chemical changes in sol-gel have been analyzed through IR spectrometry. Structure directing mechanism of EO₂₀PO₇₀EO₂₀ has also been discussed elementarily.