中文摘要：

以钛酸四丁酯为前驱物，在溶胶-凝胶法和硬脂酸法的合成样品的过程中添加正硅酸乙酯，分别合成出纳米TiO2，焙烧成晶后通过HF除去硅，形成了多孔TiO2。通过XRD、SEM、UV-Vis、BET等测试手段，比较正硅酸乙酯对不同合成方法合成的样品的影响。在对甲基橙的紫外光催化试验中，添加正硅酸乙酯再由HF处理后合成的样品表现出较高的催化活性，这与此方法合成的样品的表面积较大有关。

英文摘要：

In this paper, ZiO2 nanocrystals were prepared by stearic acid gel method and sol-gel method with additional tetraethyl orthosilicate, and then after HF treatment, it transformed to the porous TiO2 nanocrystals. The synthesized samples were characterized by X-ray powder diffraction （XRD）, scanning electron microscopy （SEM）, brunaueremmett-teller （BET） surface area and UV-Vis diffuse reflectance spectra. These nanocrystals were used for the photodegradation of methyl orange （MeO） in water under UV irradiation. It was found that the porous TiO2 nanocrystals prepared by sol-gel method exhibited the best photodegradation effect for MeO. This is rationalized by considering the BET surface area.