Synthesis and Characterization of Superparamagnetic Fe3O4 Nanoparticles

We synthesized Fe3O4 nanoparticles using a solvent thermal method and characterized the morphologies, structures, surface properties, thermal stability and magnetism of the products by Field emission scanning electron microscopy (FE-SEM), Powder X-ray diffraction (XRD), Fourier transform infrared (FTIR), thermal gravimetric analysis (TGA) and vibrating sample magnetometer (VSM). The experimental results showed that the Fe3O4 nanoparticles have a tunable average size range from 55 nm to 85 nm. Their diameters decreased with increase of precursor FeCl24H2O concentration or increase of the reaction time under other reaction conditions held constant. The XRD pattern confirmed that the Fe3O4 nanoparticles belong to cubic structure. Magnetic investigation reveals that the Fe3O4 nanoparticles have higher saturation magnetization and negligible coercivity at room temperature.