Multifunctional nanocomposites with different coupling agents: Synthesis, luminescent and magnetic properties

摘要

In this study, the co-precipitation method has been developed for the synthesized Fe_3O_4 nanoparticles which are encapsulated with SiO_2/C/TiO_2 via the facile and further functionalized by the deposition of Y_2O_3:Eu~(3+) phosphors. Transmission electron microscopy images revealed that the nanocomposites show a spherical morphology with size distribution around 100-250 nm, and the thickness of the coupling agents was 3-4 nm. The X-ray diffraction patterns showed that a cubic spinel structure of Fe_3O_4 core and a tetragonal phase of Y_2O_3:Eu~(3+) shell was obtained. The multifunctional nanocomposites showed ferrimagnetic behavior, the negligible coercivity Hc and remanence Mr at room temperature and showed unique europium fluorescence properties with strong red emission peak from the electric-dipole transition ~5D_0 → ~7F_2 of Eu ~(3+) ions at 611 nm. Therefore, the multifunctional nanocomposites are expected to develop many potential applications in biomedical fields and magnetic photocatalyst.