Superparamagnetic and light-emitting bifunctional nanocomposites of iron oxide and erbium or thulium doped yttrium orthovanadate

Advances in biomedical research have increased interest obtaining and studying new bifunctional materials for use theragnostic. Here we describe detail the preparation of magnetic-fluorescent (Y0.9Ln0.1VO4/Fe3O4)@SiO2 [(Y0.9Ln0.1VO4 @SiO2)/Fe3O4)@SiO2] nanocomposites with Ln = Er or Tm. In addition, their magnetic optical properties were carefully analyzed. The influence Fe3O4 content silica shell thickness on fluorescent emission VIS-NIR region Y0.9Ln0.1VO4 cores was evaluated as well display systems possibility directing them by means external fields. Samples prepared using wet chemistry methods involving low temperatures short reaction times. samples that are not easily oxidizable a hydrothermal method, while sample synthesized coprecipitation process which mixture precursors treated at very temperature to avoid oxidation. powder amalgamation both possible due polymeric network synthetized modified Stöber method. purity all ensured XRD FTIR techniques. Diffraction profiles show diffraction maxima can be indexed tetragonal symmetry space group I41/amd, compatible zircon structure-type YVO4 host. All reflections present profile cubic Fd3?m, characteristic an inverse spinel structure-type. amorphous incorporation also TEM images. Studies behavior luminescent intensity investigated showed dependence both, coating thickness, contact between powder.