Transparent thin films of mesoporous titania and mesoporous silica with embedded dye molecules as effective photocatalysts for pollutant mineralization and as optical gas sensors

该项目旨在制备嵌入二氧化钛簇和/或染料分子的介孔二氧化钛和介孔二氧化硅透明薄膜。该复合材料将用作废水净化的光催化剂和光学气体传感器。在光催化反应中使用透明薄膜有利于粉末悬浮液，因为可以避免光散射，并且可以将许多薄膜排成一排以实现高效率。此外，催化活性膜易于回收。薄膜的有序介孔结构将通过预先编程的有机分子的自组装聚集体产生，这确保了材料具有非常大的可接近的内表面区域。薄膜制造将通过浸涂和旋涂来完成。纯膜和功能化膜的活性将在适当的反应中进行测试，例如在水溶液中光降解酚或硫化钠。为了使日光也适用于二氧化钛薄膜，将尝试用染料分子，如酞菁，共价锚定在薄膜的内表面进行增感。这些材料在不同气体的光学传感方面的性能将被额外测试。

The project is aiming at the preparation of transparent thin films of mesoporous titania and mesoporous silica with embedded titania clusters and/or dye molecules. The composites will be used as photocatalysts for waste water purification and optical gas sensors. The use of transparent thin films in photocatalytic reactions is favourable to suspensions of powders because light scattering is avoided and a number of films can be arranged in rows to achieve high efficiencies. Furthermore, the catalytically active films can be easily recovered. Ordered mesoporous structures of films will be created by self-assembled aggregates of pre-programmed organic molecules which ensure that the materials have very large accessible inner surface areas. Film manufacturing will be done by dip-coating and spin-coating. The activity of the pure films and of the functionalized films will be tested in suitable reactions, such as photodegradation of phenols or sodium sulfide in aqueous solutions. To enable an application of daylight also for the titania films, a sensibilization by dye molecules, e.g. phthalocyanines, covalently anchored on the inner surface of the films will be attempted. The properties of those materials regarding the optical sensing of different gases will be tested additionally.