纳米二氧化钛粉体晶相控制实验研究

Experimental Study on the Control of TiO2 Nano-Powder Crystal Phases Prepared by the Hydrolysis-Sediment Approach

在水解-沉淀法制备纳米TiO2粉体的过程中,使用不同的沉淀剂获得了晶相不同的纳米TiO2粉体;使用混合沉淀剂,通过控制沉淀剂的比例,制备了晶相组成(金红石与锐钛矿比例)不同的纳米TiO2多晶粉体;采用相同的粉体制备工艺,不同的后续处理工艺,探讨了锐钛矿向金红石转变的相变温度.经分析研究后认为,水解-沉淀法制备的纳米TiO2粉体中的锐钛矿向金红石转变的温度为500～800℃,完全转变的温度在800℃以上;纳米TiO2多晶粉体的晶相组成不仅与沉淀剂的种类、混合沉淀剂中沉淀剂的比例和粉体的煅烧温度有关,而且与粉体的后续处理工艺和粉体表面界面相的稳定性有关.

While preparing TiO2 nano-powder, different additives and the ratio of mixed additives were used as precipitants, different phases of crystalline and different ratios between rutile and anatase were gotten. The transitional temperature from anatase to rutile is different with the same preparing approach and different processing manner of TiO2 nano-powder. The crystal phase of TiO2 nano-powder is controlled by the type of precipitant, the ratio of different additives in the mixing solution and preparing approach. It is also determined by the interaction between the powder's face and the precipitants and the precipitant characteristics. It depends on the stability of the interface phase during the growth of powder.