制备条件对纳米TiO2晶型及其晶相含量影响的研究

分别用TiCl4，Ti(SO4)2和Ti(OC4H9)4为原料制备纳米二氧化钛粉体。用XRD和TEM对纳米二氧化钛粉体的晶型及晶粒形貌进行了分析。研究了在同一条件下制备的3种纳米二氧化钛粉体对光催化降解亚甲基蓝溶液的影响；结果表明：在相同的制备条件下，用TiCl4为原料制备的纳米二氧化钛晶型较易控制，容易得到含有一定金红石相、催化活性较高的混合晶型的纳米二氧化钛；因此，其降解效果优于其他两种。同时研究了外界条件(如分散剂、干燥方式、温度及烧结温度等)对纳米二氧化钛晶相及其含量变化的影响。实验结果为：用异丙醇做分散剂时，当分散剂与水的体积比为3时，选用冷冻干燥法可得到均分散的粒度可控的球形纳米二氧化钛晶粒。

Influence of Preparation Conditions on Nano TiO2 Crystal Phase Structure

TiO 2 nanopowders were prepared by hydrolyzing titanium salt and characterized by XRD and TEM for obtaining the crystal types and the morphology. Comparing with hydrolyzing Ti(SO 4) 2 and Ti(OC 4H 9) 4, the TiO 2 nanopowders with excellent photocatalysed activity property are obtained easily by hydrolyzing TiCl 4 in the same conditions, which represent the highest efficiency for photocatalytic degradation of methylene blue. The effect factors on the crystal phase content of TiO 2 nanopowders, including dispersant solution, drying methods and calcining temperature etc, were investigated too. The results show that the uniform sphere TiO 2 nanopowders may be obtained when the volume ration of isopropylalcohol and water reached 3 by freeze drying method.