A simple solvothermal synthesis and characterization of round-biscuit-like Fe3O4 nanoparticles with adjustable sizes

Round-biscuit-like Fe3O4 nanoparticles were successfully prepared in large-scale by a simple solvothermal method. The sizes of the particles can be readily tuned from 15 to 150 nm by adjusting the experimental parameters such as solvothermal temperature, reaction time, the initial concentration of the reactants, and molar ratio of FeCl3 and protective reagents. Structure, morphology and size products were investigated in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and scanning electron microscopy (SEM). Magnetic studies revealed that the saturation magnetization ( M s ) increases as the particle size increases.