TiO_2/SiO_2复合薄膜的制备及自清洁性能研究

Study on Preparation and Self-cleaning Properties of TiO_2/SiO_2 Composite Thin Films

采用溶胶-凝胶(Sol-Gel)法,并结合浸渍—提拉工艺,以钛酸丁酯、正硅酸乙酯为钛源和硅源,无水乙醇为溶剂,制备了稳定的TiO_2和SiO_2溶胶;再根据不同的镀膜顺序,制备出纳米TiO_2/SiO_2复合薄膜.利用扫描电子显微镜(SEM)、紫外-可见分光光度计、接触角测量仪等对TiO_2/SiO_2复合薄膜的表面形貌、透光性和亲水性能等进行了分析,研究了溶胶浓度、摩尔配合比、镀膜顺序等对复合薄膜结构和自清洁性能的影响.实验结果表明:当溶胶浓度为0.5,mol/L时,按TiO_2/SiO_2/TiO_2/TiO_2(TSTT)镀膜顺序制备的纳米TiO_2/SiO_2复合薄膜,经紫外灯照射1,h后水接触角小至2.5°,表现出超亲水自清洁性能.

In this experiment,the uniform,transparent nano-TiO2/SiO2 films are prepared by sol-gel method and dipcoating method on glass substrate using transparent TiO2 sol and transparent SiO2 sol which was compounded by butyl titanate（TBOT）and tetraethyl orthosilicate（TEOS）as precursor,absolute ethanol as solvent.The effects of sol concentration,the molar ratio of SiO2 sol and TiO2 sol,and the different order of coating on the structure,surface morphology,hydrophilicity and transmittance of the films are characterized by scanning electron microscope（SEM）,ultraviolet-visible pectrophotometer and dynamic contact angle measurement.The results show that the water contact angle of TiO2/SiO2composite thin film is 2.5° after one hour ultraviolet lamp raying,which shows a good self-cleaning property,when the sol concentration and the coating order of nano-TiO2/SiO2 composite thin film is 0.5 mol/L and TiO2/SiO2/TiO2/TiO2（TSTT）.