Magnetic Properties Change in Fe3O4 Nanoparticles Grown under Magnetic Fields

摘要

Magnetite nanoparticles Fe3O4 have been synthesized under magnetic fields by the method of co-precipitation. XRD and TEM studies reveal that higher strength of magnetic field in the process tends to result in formation of larger grains with better crystallinity. The magnetic measurements show that the powders obtained under magnetic field possess excellent magnetic properties. The improved magnetic properties were suggested to be originated from the thinner nonmagnetic layer and strengthened superexchange interactions of Fe-O-Fe due to magnetic field making Fe3O4 nanoparticles well crystallinity.