Determination of size distributions in nanosized powders by TEM, XRD, and SAXS
Determination of size distributions in nanosized powders by TEM, XRD, and SAXS
复制标题
DOI：
10.1080/17458080600752482
复制
发表时间：
2006-01-01
影响因子：
2.8
通讯作者：
Sogaard, E. G.
中科院分区：
文献类型：
--
作者：
Jensen, H.;Pedersen, J. H.;Sogaard, E. G.
采用透射电镜（TEM）、x射线粉末衍射（XRD）和小角x射线散射（SAXS）对3种市售TiO2粉末（P25、UV100和TiO2_5 nm）和1种SSEC生产的粉末（SSEC78）的晶粒尺寸分布和粒度分布进行了测定。将理论Guinier模型拟合到实验得到的XRD数据中，并与解析表达式进行了比较。对XRD谱的建模表明，分析粒度表达式与理论Guinier模型存在差异。采用包含颗粒间干扰因子的硬球模型从SAXS测量数据中提取了初级粒度分布。SAXS法得到的颗粒尺寸小于XRD法得到的颗粒尺寸；然而，两种技术之间获得了很好的一致性。电子显微镜证实了XRD和SAXS得到的主要颗粒尺寸和形状。SSEC78粉末和市售粉末的形貌不同，但SSEC78、UV100和TiO2_5nm都是由初级颗粒和纳米级初级颗粒团聚成更大簇的二级结构组成。P25显示出最大的初级颗粒大小，但不显示二级结构。
Crystallite size distributions and particle size distributions were determined by transmissions electron microscopy (TEM), X-ray powder diffraction (XRD), and small-angle X-ray scattering (SAXS) for three commercially available TiO2 powders (P25, UV100, and TiO2_5 nm) and one SSEC produced powder (SSEC78). The theoretical Guinier model was fitted to the experimental obtained XRD data and compared to analytical expressions. Modeling of the XRD spectra showed a difference between the analytical size dependent expressions and the theoretical Guinier model. Primary particle size distributions were extracted from SAXS measurements by the hard sphere model including an interparticle interference factor. The sizes obtained from SAXS were smaller than the sizes obtained from the XRD experiments; however, a good agreement was obtained between the two techniques. Electron microscopy confirmed the primary particle sizes and the shapes obtained by XRD and SAXS. The SSEC78 powder and the commercially available powders showed different morphologies, but SSEC78, UV100, and TiO2_5nm all consisted of both primary particles as well as a secondary structure comprised of nanosized primary particles agglomeration into larger clusters. P25 showed the largest primary particle size, but did not show a secondary structure.