Facile Hydrothermal Synthesis and Growth Kinetics of Fe-Based Magnetic Nanoparticles

The facile hydrothermal method was used to synthesize Fe3O4 nanoparticles with an average diameter of 11 nm. The pure body-centered cubic (bcc)-Fe nanoparticles were prepared by reduction of Fe3O4 nanoparticles powder in H2 atmosphere. The structure, morphology and magnetic properties of the products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis-differential scanning calorimetry (TGA-DSC) and vibrating sample magnetometer (VSM). The results showed that the as-prepared Fe3O4 nanoparticles had a relatively homogeneous size. The particle diameters became bigger with the increase of reaction time. The growth kinetics of the Fe3O4 nanoparticles was also briefly discussed. The products exhibited superparamagnetic properties at room temperature and the specific saturation magnetization was dependent on the particle sizes.