文献类型：期刊文献

中文题名：TiO_2/SiO_2/CeO_2复合纳米薄膜超亲水性能的研究

英文题名：Super-Hydrophilicity of TiO_2/SiO_2/CeO_2 Composite Thin Films

作者：关凯书[1];姜秋鹏[2];尹衍升[3]

机构：[1]华东理工大学化工机械研究所,上海200237;[2]山东莱阳农学院工程系,山东莱阳265200;[3]山东大学南校区材料学院材料液态结构及其遗传性教育部重点实验室工程陶瓷省重点实验室,山东济南250061

年份：2003

卷号：21

期号：3

起止页码：291

中文期刊名：中国稀土学报

外文期刊名：Journal of the Chinese Society of Rare Earths

收录：CSTPCD;;Scopus;北大核心:【北大核心2000】；CSCD:【CSCD2011_2012】；

语种：中文

中文关键词：无机非金属材料;超亲水性;溶胶-凝胶工艺;氧化钛/氧化硅复合薄膜;稀土

外文关键词：inorganic non-metal materials; super-hydrophilic property; sol-gel method; TiO_2/SiO_2 composite films; rare earth

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 CeO2超亲水性薄膜,并用X射线衍射、傅立叶红外光谱、紫外 可见分光光度计研究了SiO2及稀土铈添加对TiO2薄膜表面特征及超亲水性能的影响。结果表明,TiO2 SiO2 CeO2薄膜亲水性能及亲水持续效应显著提高。实验中掺杂的铈是以三价离子态引入的,由于Ce3+在高温下很容易氧化,故在薄膜中铈主要以四价态形式存在。Ce4+在光激发下很容易捕获光生电子生成Ce3+离子,光生空穴则与表面氧离子反应形成氧空位,而氧空位对亲水性的提高具有关键作用。添加SiO2后,薄膜表面的羟基含量增加,这主要是由于TiO2与SiO2复合在表面形成Lewis酸所致。表面稳定的羟基可使亲水性在暗中保持较长时间,因而亲水持续效应提高。添加SiO2及稀土铈后,薄膜中TiO2晶粒尺寸变小,量子效应增强,这也导致亲水性提高。因此添加稀土铈及SiO2后,薄膜表面的氧空穴增多,薄膜的超亲水性及亲水持续效应提高。
CeO2 doped SiO2/CeO2 composite films were prepared by solgel method and characterized by means of Xray diffraction. Fourier transform infrared spectroscopy (FTIR), Ultravioletvisible spectroscopy. The measurement of contact angle of a water droplet on the films showed that the addition of SiO2 and CeO2 in the TiO2 films enhances superhydrophilic property under UV irradiation and this property can maintain for a long time after removal of UV irradiation. During the rpocess, Ce3+ in sol solution is easily transformed to Ce4+, which is the existent form in the composite films, calcined at high temperature. Because of the low redox potential between Ce4+ and Ce3+, Ce4+ receives lightinduced electron and is reduced to Ce3+, lightinduced hole reacts with oxygen ion and produces an oxygen vacancy which tends to make the surface hydrophilic. The FTIR analysis revealed that the surface of a TiO2/SiO2 film has more hydroxyl groups than that of a pure TiO2 film because of the forming of lewis acidity. The stable hydroxyl groups on the surface can dissociate water adsorption which results in increasing of superhydrophilicity. So the Ti3+-OH structure can maintain for a long time, which means that superhydrophilic state of the TiO2/SiO2 films can maintain for a long time in dark place. The smaller grain size also enhances the superhydrophilicity owing to quantum size effects. So with the synergetic effect of SiO2 and CeO2, the hydroxyl content and oxygen vacancies increase in composite films, and the photoinduced superhydrophilic property of TiO2/SiO2/CeO2 increases and can maintain the superhydrophilic property.