Synthesis and Characteristic of the NaYF4/Fe3O4@SiO2@Tb(DBM)3 . 2H2O/SiO2 Luminomagnetic Microspheres with Core-Shell Structure.

The structure and properties of the multifunctional nanoparticles were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Photoluminescence spectra and Vibrating sample magnetometer (VSM). The experimental results show that the microsphere has the magnetic core and silica shell bonded with terbium complex. These multifunctional nanoparticles exhibit strong visible emission and up-conversion emission, which is based on the use of up-converting nanoparticles (UCNPs) of the NaYF4:Yb3+, Er3+/Tm3+ type that can be excited with 980 nm laser light to give a green and red luminescence, moreover, nanoparticles possess magnetism with a saturation magnetization of 18.48 emu/g and paramagnetism at room temperature.