Preparation and magnetic properties of FeSi/SiO_2 nanocomposites with core-shell structure

摘要

FeSi/SiO_2 Core-shell nanoparticles were synthesized by DC arc-discharge approach and annealing process. The products were characterized by SEM, TEM, EDX, XRD and VSM. As-prepared FeSi/SiO_2 Core-shell nanoparticles have the diameter of 40-100 nm and the thickness of the SiO_2 shell is about 20 nm. The growth mechanism based on the crystallographic and thermodynamic theory was explained. Magnetic characterization was carried out and the results showed that the FeSi/SiO_2 Core-shell nanoparticles exhibited superparamagnetism characteristic at room temperature.