Structure of hollow spheres analyzed by X-ray diffraction, transmission electron microscopy, and dynamic light scattering

The structural properties of nanoscale Ag, La(OH)3, CuS (covellite), Ag2S (acanthite), and ZnO hollow spheres, massive Ag nanoparticles and In–Ag core–shell nanoparticles with outer diameters between 200 and 400 A, were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM), dynamic light scattering (DLS), and differential sedimentation (DS). Lognormal size distributions of single-crystalline (quasi)spherical nanoparticles are found in our samples by DLS, STEM, DS, and HRTEM. The lattice parameters of the nanomaterials are determined by XRD line–position analysis, while the volume-averaged size and the microstrain are derived by the average-size and strain approximation in the integral breadth method. A new expression is presented in this work to derive the real average outer diameter $$ \bar{D} $$ of hollow spherical particles. The good agreement between $$ \bar{D} $$ and the corresponding diameter determined by DLS in the case of Ag and La(OH)3 hollow spheres demonstrates the validity of the approach. The same expression is applied to derive the average wall thickness of CuS and Ag2S hollow spheres as well as for the Ag shell thickness of In–Ag core–shell nanoparticles.