Characterizing Size and Porosity of Hollow Nanoparticles: SAXS, SANS, TEM, DLS, and Adsorption Isotherms Compared
Characterizing Size and Porosity of Hollow Nanoparticles: SAXS, SANS, TEM, DLS, and Adsorption Isotherms Compared
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DOI：
10.1021/la302236u
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发表时间：
2012-10-30
期刊：
影响因子：
3.9
通讯作者：
Ungar, Goran
中科院分区：
文献类型：
--
作者：
Chen, Zhi Hong;Kim, Chanhoi;Ungar, Goran
采用透射和掠入射小角 X 射线散射（SAXS 和 GISAXS）、小角中子散射 (SANS)、透射电子显微镜 (TEM)、动态光散射 (DLS) 和 N-2 吸附-解吸等温线等实验方法相结合，对尺寸在 25 至 100 nm 之间的 SiO2/TiO2 空心纳米颗粒 (HNP) 进行了表征。在SAXS、SANS和GISAXS数据的分析中，使用了解耦近似和Percus-Yevick结构因子近似。 N-2等温线的处理采用Bninauer-Emmett Teller、t图和基于Kelvin方程的球形孔隙模型。从散射和 TEM 方法中提取的参数是平均外径和内径以及多分散性。对于这些提取的参数，不同方法之间取得了良好的一致性。讨论了不同方法的优点、优点和缺点。此外，这些方法的结合为我们提供了有关 HNP 壳的孔隙率和壁内孔尺寸的信息，这对于 HNP 作为药物输送载体和催化剂载体的应用至关重要。
A combination of experimental methods, including transmission and grazing incidence small-angle X-ray scattering (SAXS and GISAXS), small-angle neutron scattering (SANS), transmission electron microscopy (TEM), dynamic light scattering (DLS), and N-2 adsorption-desorption isotherms, was used to characterize SiO2/TiO2 hollow nanoparticles (HNPs) of sizes between 25 and 100 nm. In the analysis of SAXS, SANS, and GISAXS data, the decoupling approximation and the Percus-Yevick structure factor approximation were used. Bninauer-Emmett Teller, t-plot, and a spherical pore model based on Kelvin equation were applied in the treatment of N-2 isotherms. Extracted parameters from the scattering and TEM methods are the average outer and inner diameters and polydispersity. Good agreement was achieved between different methods for these extracted parameters. Merits, advantages, and disadvantages of the different methods are discussed. Furthermore, the combination of these methods provided us with information on the porosity of the shells of HNPs and the size of intrawall pores, which are critical to the applications of HNPs as drug delivery vehicles and catalyst supports.