匀胶法制备TiO_2薄膜的亲水性研究

Study on hydrophilicity of TiO_2 films prepared by spin coating method

利用匀胶机制备不同厚度TiO2薄膜,分别用X射线衍射仪(X-ray Diffraction,XRD)、拉曼(Raman)光谱、原子力显微镜(Atomic Force Microscope,AFM)和X射线光电子能谱(X-ray photoelectron Spectroscopy,XPS)表征薄膜微观结构;利用紫外-可见分光光度计(UV-Vis)研究薄膜厚度对光透过率的影响;通过表面接触角测试仪研究TiO2薄膜厚度对其亲水性的影响.实验结果表明:匀胶二层的TiO2薄膜(厚度约为170nm)可达到最佳亲水性;TiO2表面形貌和表面羟基官能团(-OH)的含量会对薄膜亲水性造成影响;继续增加TiO2薄膜厚度不利于改善薄膜亲水性.

TiO2films with different thickness have been deposited on slide glass substrates by spin coating technique.Microstructures of the films are characterized by X-ray diffraction,Raman spectra,atomic force microscopy,X-ray photoelectron spectroscopy,and UV-Vis spectrophotometer is employed to study the effects of the thickness on transmittance.The wettability transformation of the films under UV light irradiation was investigated by using a contact meter.The results demonstrated that the film with two layers（the thickness is about 170nm）has already gotten the best wettability.The hydrophilicity of the films can be influenced by the surface morphology and the content of hydroxyl groups（-OH）.Increasing the thickness won’t improve the hydrophilicity of the films when the thickness of the films reaches the threshold value.