中文摘要：

以水溶性壳聚糖为添加剂，采用溶胶-凝胶法制备纳米TiO2光催化剂。利用粒度分析、热重分析、X射线衍射对胶体及纳米TiO2进行表征，以甲基橙为模型反应评价纳米TiO2的光催化性能。结果表明，煅烧温度达到500℃时水溶性壳聚糖分解完全，粉末以锐钛矿晶型为主；添加剂使胶体颗粒变小；纳米TiO2具有较高的光催化活性，反应50min时，甲基橙的降解率可达（99±1）％。

英文摘要：

Nanosized TiO2 has been prepared by sol-gel technique with water-soluble chitosan as additive. The properties of colloid and nanosized TiOz were characterized by particle size analysis, thermal analysis （TG and DTG） and XRD. The photocatalytic performance of the nanosized TiO2 was evaluated by degradation of methyl orange. When the calcined temperature was up to 500℃, the additive was completely decomposed and the nanosized TiO2 was mainly in anatase. The colloidal particle was redueed with watersoluble chitosan as additive. Nanosized TiO2 has high photocatalytic activity, when the photocatalytic reaction time was 50 min, the degradation rate of methyl orange was up to （99 ＋1） %.