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

Bifunctional nanostructures based on ZnO nanoparticles (NPs) with controlled Gd2O3 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 Gd2O3 shell leads to an increase of the ZnO particles size up to 80-160 nm and the formation the Gd2O3 shell with size of 2-4 nm. The dependence of the phase composition, luminescent and magnetic properties on Gd2O3 content are also discussed.