光催化多孔TiO_2薄膜的表面形貌对亲水性的影响

EFFECTS OF SURFACE MORPHOLOGY OF PHOTOCATALYTIC POROUS TiO_2 THIN FILMS ON HYDROPHILICITY

:从含聚乙二醇 (PEG)的钛醇盐溶胶前驱体中通过溶胶 -凝胶工艺在普通钠钙玻璃表面制备了多孔锐钛矿型TiO2 纳米薄膜 .用扫描电镜 (SEM )、X射线光电子能谱 (XPS)和红外光谱 (IR)分析了TiO2 薄膜表面的微结构 ,结果表明 :随着前驱物中聚乙二醇的加入量和分子量的增加 ,聚乙二醇热分解后的薄膜中产生的气孔就越多且孔径越大 ,同时TiO2 薄膜表面的羟基含量增加且表面粗糙度增大 .接触角测试表明 :随着薄膜中气孔数量的增多和孔径增大 ,薄膜表面的亲水性增强 ,水与薄膜表面的接触角下降为 0° .分析了多孔TiO2 薄膜表面的超亲水机理 .

The porous TiO 2 anatase nanometer thin films deposited on soda-lime glass were prepared from titanium alkoxide solutions containing polyethylene glycol(PEG) by sol-gel processing. The surface microstructure of TiO 2 thin films was analyzed with scanning electron microscopy(SEM), X -ray photoelectron spectroscopy(XPS) and infrared (IR) spectra. The results showed that with increasing of the amount and molecular weight of PEG addition to the precursor solution, the quantity and size of pores were increased in the resultant thin films as a result of the decomposition of PEG during heat_treatment. At the same time, the adsorbed hydroxyl content and roughness of such porous thin films were also found to increase due to the larger size and more pores in the thin films. The results of contact angle measurement showed that with increasing of the quantity and size of pores the hydrophilicity of the as_prepared porous thin films was enhanced and the contact angle between water and the porous TiO 2 thin films quickly dropped to zero. The super_hydrophilic mechanism of the porous TiO 2 thin films surface was studied.