Synthesis and study of bifunctional core–shell nanostructures based on ZnO@Gd2O3

Bifunctional nanostructures based on ZnO nanoparticles (NPs) with controlled Gd 2 O 3 shell thicknesses were obtained by simple low-temperature methods (sol–gel technique and seed deposition method). The morphology, nanostructure, phase and chemical composition as well as luminescent and magnetic properties of the obtained core–shell nanostructures were investigated by transmission electron microscopy (HRTEM), energy dispersive x-ray spectroscopy (EDS), x-ray diffraction (XRD) techniques, optical spectroscopy, and SQUID magnetometer. As-obtained ZnO NPs are highly monodispersed and crystalline with mean particles size distribution of about 7 nm. Modification of the ZnO NPs surface by Gd 2 O 3 shell leads to an increase of the ZnO particles size up to 80–160 nm and the formation the Gd 2 O 3 shell with size of 2–4 nm. The dependence of the phase composition, luminescent and magnetic properties on Gd 2 O 3 content are also discussed.