Gold-coated iron nanoparticles were fabricated by a two-step reverse micelle method. The core-shell structure of nanoparticles where an Fe core is surrounded by Au shell was revealed by TEM, XRD and EDS. This structure shows that the Au shell was formed on the surface of the Fe core before the coalescence of nanoparticles. The UV-vis absorption spectrum of colloidal nanoparticles exhibited an absorption band at 526 nm and magnetic measurements indicated that the nanoparticles are superparamagnetic at room temperature.
Keywords: Nanoparticles, Core-shell structure, Reverse micelle method, Magnetic property.