铈掺杂对二氧化钛纳米颗粒微结构的影响

The effect of Ce-doping on microstructure of TiO_2 nanoparticles

报道了铈掺杂对二氧化钛纳米颗粒微结构的影响。用溶胶—凝胶方法制备了不同铈含量的TiO_2纳米颗粒,在不同的温度下煅烧得到纳米样品系列。用X射线衍射(XRD)、小角X射线散射(SAXS)以及X射线吸收谱(XAFS)技术研究了铈离子掺杂和煅烧温度对二氧化钛纳米颗粒微结构的影响。结果发现:铈离子的掺入有效地抑制了二氧化钛纳米颗粒的生长和在高温下的相变。纳米颗粒"自相似"的分形结构与铈含量和煅烧温度有关。用核心一壳层模型描述了钛的近邻原子结构。

The effect of Ce-doping on microstructure of TiO_2 nanoparticles is reported in this paper. The Ce-doped TiO_2 samples were prepared by the sol-gel method under acidic condition and calcined at different temperatures. Influence of the cerium dose and calcination temperature on the microstructure of the TiO_2 nanoparticles was studied by X-ray diffraction (XRD), small angle X-ray scattering(SAXS) and X-ray absorption fine structure techniques. It is found that the cerium doping inhibits the growth of nanoparticles and the transformation of anatase to rutile at elevated temperature. The 'self-similar' fractal structures are dependent on the Ce content and annealing temperature. The core-shell model was used to describe the near-neighbour structural parameters around Ti.