Synthesis and magnetic properties of CoFe2O4 nanoparticles

Abstract

CoFe2O4 nanoparticals were synthesized by sol-gel method, using polyvinyl alcohol (PVA) and polyethylene glycol (PEG) as dispersants and gelatas, respectively. The morphology, size and magnetic properties of the nanoparticals were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), physical property measurement system (PPMS), respectively. The magnetic properties of the nanoparticals prepared using PVA was compared with that prepared using PEG, meanwhile the influence of different dosages of PEG on the magnetic properties of CoFe2O4 nanoparticals was investigated as well. The results indicate that the saturation magnetization of the nanoparticals prepared using PEG (143.11 emu/g) is much larger than that of the nanoparticals prepared using PVA (62.81 emu/g), which is mostly due to the redistribution of Co2+ in A site and B site. The size of CoFe2O4 nanoparticles is one of important factors determining the saturation magnetism of CoFe2O4 nanoparticles, which is different when the amount of the PEG is different. In summary, the morphology, size and the magnetic properties of CoFe2O4 nanoparticles are all optimized when prepared using 4 g PEG.