纳米板钛矿基TiO_2的晶粒尺寸效应

Size effect on crystallite microstructure in nanocrystalline brookite-based TiO_2.

借助精确的 X射线衍射测量 ,结合独立衍射峰对不同晶粒度纳米板钛矿基 Ti O2 样品中板钛矿和金红石相的微结构参量进行了较细致的研究 ,给出了标征物相、晶面指数 (hk1)和晶面间距 dhkl值 ,详细分析结果的系列 XRD谱 ,并得到晶面间距、晶格常数、轴比、晶胞体积等参数数值及其相对常规粗晶的变化情况 ,从而初步揭示出其晶粒微结构的尺寸效应 .作者首次发现 ,纳米板钛矿基 Ti O2 样品中板钛矿和金红石相晶粒均存在着非单调的各向异性晶格畸变 .

By using XRD (X-ray diffraction) technique, the microstructure parameters of nanocrystalline brookite-based TiO-2 specimens of various grain sizes are investigated. From the obtained experimental results of the size effect on microstructure, it has been found that there exists a nonmonotonous and anisotropic lattice distortion in the brookite-phase and anatase-phase of these novel nanomaterial TiO-2 crystallites.