Synthesis and magnetic properties of iron/silica core/shell nanostructures

Magnetic iron/silica core/shell nanostructures were prepared by reducing the initially formed α-Fe2O3/SiO2 composites prepared via a sonication-assisted Stöber process. Monodisperse α-Fe2O3 nanocrystals were prepared by a simple solution method using PEG as a surfactant. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra, (high-resolution) transmission electron microscopy ((HR)TEM), scanning electron microscopy (SEM) and magnetic hysteresis loops. After the reduction process, the silica coating can protect the Fe core from oxidation effectively. And the formed Fe/SiO2 nanostructures show better magnetic behavior, which is promising in targeted drug delivery systems.