氧供体醇对非水解溶胶-凝胶法制备TiO_2薄膜结构及性能的影响

EFFECT OF THE OXYGEN DONORS ON STRUCTURE AND PHOTOCATALYSIS OF TiO_2 FILMS BY NON-HYDROLYTIC SOL-GEL

以TiCl4为前驱体,聚乙二醇为添加剂,分别采用无水甲醇、无水乙醇和无水异丙醇为氧供体,采用非水解溶胶-凝胶法制备了TiO2薄膜。应用X射线衍射、场发射扫描电镜和光照甲基橙的降解实验研究了氧供体醇种类对TiO2溶胶的胶凝时间、TiO2薄膜显微结构和光催化活性的影响。结果表明:当乙醇为氧供体时,TiO2溶胶的胶凝时间最长,甲醇次之,异丙醇最短。相对于甲醇和异丙醇为氧供体,以无水乙醇为氧供体时,TiO2薄膜中所含无定形含量最少,具有光催化作用的锐钛矿含量最多,薄膜呈现均匀的多孔结构,光催化性能最佳。

TiO2 thin films were prepared via non-hydrolytic sol-gel route using absolute methanol, absolute ethanol and absolute isopropanol respectively as an oxygen donor, TiCl4 as a precursor, and polyethylene glycol （PEG） as a film-forming agent. The effect of the oxygen donors on gelation time of TiO2 sol, microstructures and photocatalysis of TiO2 films were studied by the X-ray diffraction （XRD）, the field emission scanning electron microscopy and the photocatalytic degradation of methyl orange under ultraviolet irradiation. The results indicate that when the oxygen donor is absolute ethanol, the gelation time of TiO2 sol is the longest, and the absolute isopropanol has the shortest gel time. Compared with absolute methanol and absolute isopropanol, the TiO2 film using absolute ethanol as an oxygen donor contains the least amorphous phase and the crystallization rate of anatase TiO2 is the highest. The film using absolute ethanol as an oxygen donor has the highest TiO2 content for photocatalysis, and the best photocatalytic property.