(1. 山东大学 材料液态结构及其遗传性教育部重点实验室,
山东省工程陶瓷重点实验室, 济南 250061;
2. 华东理工大学 化工机械研究所, 上海 200237;
3. 黑龙江农垦科学院工程所, 佳木斯 154007)
摘 要: 采用溶胶-凝胶法在载玻片表面制备了均匀透明的TiO2/SiO2超亲水性薄膜。 利用XRD、红外光谱(IR)和分光光度计, 研究了SiO2添加量对薄膜微结构、透光率、亲水性的影响。 结果表明: 添加SiO2后, 薄膜中TiO2晶粒尺寸变小; 在薄膜中, TiO2和SiO2分别单独形成颗粒, 但有部分Ti—O—Si键形成, 存在部分复合氧化物; 由于取代反应, 复合氧化物中表面形成Lewis酸, 薄膜表面吸附的羟基含量增多且稳定, 可提高TiO2薄膜的超亲水特性, 其超亲水性状态在暗处可保持很长时间; SiO2添加量为40%时的薄膜亲水性最好。
关键字: 溶胶-凝胶法; TiO2/SiO2薄膜; 超亲水性
super hydrophilic property of TiO2 films
(1. Key Lab for Liquid Structure and Heredity of Material, Ministry of Education, Engineering Ceramics Key Lab of Shandong Province,
Shandong University, Ji′nan 250061, China;
2. Research Institute of Chemical Equipment,
East China University of Science and Technology, Shanghai 200237, China;
3. Heilongjiang Academy of Land Reclamation Sciences, Jiamusi 154007, China)
Abstract:The relationship between the effect and the amount of SiO2 addition on photo-generated hydrophilicity of TiO2 thin film was investigated by X-ray diffraction, UV-VIS spectrum and FTIR. It is found that the addition of 40% SiO2 in mole fraction to TiO2 is the most effective for contact angle of water. The SiO2 addition has a suppressive effect on the crystal growth of TiO2 in calcination, and the absorption edge TiO2-SiO2 film shows a pseudo‘blue shift’owing to quantum size effects. SiO2 and TiO2 form single oxide particle in the film, but a part of complex oxide may be formed also. The Ti—O—Si bond in TiO2/SiO2 film increases the acidity and forms Lewis acid which results the increasing of the hydroxyl content in the composite films. The hydrophilicity and the capability of holding absorbed water of TiO2/SiO2 film are increased during UV irradiation, and the super-hydrophilic state can be maintained for a long time in dark place.
Key words: sol-gel; TiO2/SiO2 composite films; super-hydrophilic property