稀土元素(Ce)在TiO_2基体中的掺杂机理研究

Study on the doped mechanism of lanthanum(cerium) in TiO_2 substrate

采用沉淀法、胶溶法、浸泡沉淀法制备了TiO2纳米粉体和CeO2/TiO2复合纳米粉体,通过TEM、HREM对粉体的形貌进行了表征,结果表明通过简单的稀土离子掺杂可以得到粒径均匀、颗粒细小的纳米粉体,其平均粒径从25 nm减至8 nm,并运用分子杂化轨道理论和晶体生长理论对稀土元素细化晶粒的作用进行了解释。

Ultrafine TiO2 powder and CeO2/TiO2 composites were prepared by precipitation, colloidal chemical method and intrusive precipitation method. The appearance of the obtained powders was characterized by TEM and HREM method,and the result showed that uniform and ultrafine nano-particle can be obtained by simple doping lanthanum in TiO2 substrate, the average particle size decreased from 25 nm to 8 nm. The grain refining properties of lanthanum were explained by hybrid orbital theory and crystal growth principles.