多孔TiO_2薄膜的制备及其透光性能

利用溶胶-凝胶法制备了锐钛型TiO2薄膜。通过改变溶胶压热陈化温度、时间,得到了不同晶粒及孔径尺寸、不同透光率的薄膜。TG-DSC及FTIR分析表明,乙酰丙酮已结合到高分子链上,随溶胶陈化温度的上升及陈化时间的延长,干凝胶中的有机质的量下降,并能够在较低的温度下充分分解。XRD的测试结果表明,TiO2薄膜的晶粒尺寸随陈化时间的延长而减小。对薄膜的TEM观察发现,微结构呈蜂窝状,随着溶胶陈化时间的延长,相应薄膜的孔径尺寸减小,孔壁变薄。气孔的形成主要是干凝胶中的有机质在200～400℃时的氧化分解所致,其大小及分布主要取决于干凝胶中所含有机质的成分。80℃下陈化24h及150℃下陈化2h溶胶制备的薄膜其透光性能较佳,500nm透光率最高分别达到了96%及90%。

Preparation and light transmittance of porous TiO_2 film

TiO_2 films with different crystalline particle size,pore size and light transmittance were prepared by sol-gel method through varying the aging temperature and period.TG-DSC and FTIR analysis for the dried gel film indicated that acetylacetone has been bounded to the polymer chain,and the amount of organic components in the gel decreases as the aging temperature or period increase.XRD results revealed that the crystalline size decreases with the aging period increase.TEM observation suggested that the prepared film shows a honeycomb microstructure,and both the pore size and the wall thickness decrease with the aging period increase.The pores formed mainly due to the Oxidation and degradation of organic components,and the pore size depended on the composition of organic components.The films prepared with sols aged at 80℃ for 24 h or at 150℃ for 2 h performed an excellent light transmittance of 96% and 90% respectively.