Synthesis and Magnetic Properties of PEG-Modified Fe3O4 Nanospheres

PEG-modified Fe3O4 nanospheres with size distribution of about 200 similar to 400 nm were prepared by a one-step synthesis method. The products were characterized by X-ray diffraction (XRD) patterns, Fourier transform infrared (FT-IR) spectra, transmission electron microscope (TEM) and scanning electron microscope (SEM). The results reveal that the concentration of PEG has great effects on the phase composition and the morphology of the products. PEG can act as a structure-directing agent and a surface-protective agent protecting the Fe3O4 solid spheres from being oxidization. The relatively high M-s value makes the resultant Fe3O4 nanosphere an excellent agent for biomedical applications.