采用酸催化的溶胶-凝胶法制备出了纳米TiO2光催化剂,以甲基橙的光催化降解为探针反应,评价了其光催化活性.运用XRD、TEM、FT-IR以及PL光谱技术对纳米TiO2的微晶尺寸、晶体结构、表面组成和性能进行表征.结果表明,400℃焙烧的TiO2纳米粒子的颗粒形貌为近球形,晶粒尺寸为11.69nm,样品分散性良好的锐钛矿型结构.在光催化降解甲基橙的实验中,400℃焙烧的TiO2纳米粒子表现出最高的光催化活性,这与表征结果一致.此外,550℃和650℃焙烧的具有锐钛矿型和金红石型混晶结构的TiO2纳米粒子,无混晶协同促进效应. Nanometer TiO2 photocatalyst was prepared by acid-catalyzed sol-gel method, and its photocatalytic activity was evaluated by photocatalytic degradation of methyl orange as probe reaction.Using XRD, TEM, FT-IR and PL spectroscopy The crystallite size, crystal structure, surface composition and properties of nano-TiO2 were characterized.The results show that the morphology of nano-TiO2 calcined at 400 ℃ is nearly spherical, the grain size is 11.69nm, the anatase Type structure.In the experiment of photocatalytic degradation of methyl orange, TiO2 nanoparticles calcined at 400 ℃ showed the highest photocatalytic activity, which is consistent with the characterization results.Furthermore, the photocatalytic degradation of methyl orange with anatase and TiO2 nanoparticles with rutile mixed crystal structure without synergistic effect of mixed crystal.