Sonochemical synthesis, structure and magnetic properties of air-stable Fe3O4/Au nanoparticles

摘要

Air-stable nanoparticles of Fe3O4/Au were prepared via sonolysis of a solution mixture of hydrogen tetrachloroaureate( III) trihydrate ( HAuCl4) and ( 3-aminopropyl) triethoxysilane ( APTES)-coated Fe3O4 nanoparticles with further drop-addition of sodium citrate. The Fe3O4/Au nanoparticles were characterized by x-ray powder diffraction ( XRD), ultraviolet-visible spectroscopy ( UV-vis), scanning electron microscopy ( SEM) with energy dispersive spectroscopy ( EDS), transmission electron microscopy ( TEM), x-ray photoelectron spectroscopy ( XPS) and superconducting quantum interference device ( SQUID) magnetometry. Nanoparticles of Fe3O4/Au obtained under appropriate conditions possess a very high saturation magnetization of about 63 emu g(-1) and their average diameter is about 30 nm.