Magnetite-functionalized graphene nanohybrids: Preparation and characterization of electrical and magnetic property

© 2018 Elsevier Ltd. In this work, magnetite (Fe3O4)-graphene hybrid nanocomposites were successfully synthesized through a facile in-situ deposition using expandable graphite as the graphene precursor. The expandable graphite firstly underwent a rapid thermal expansion into expanded graphite (EG). Then, ultrasonication was used to further exfoliate the EG into graphene sheets. In the presence of graphene, iron (II) and iron (III) chlorides were precipitated, which resulted in the formation of the Fe3O4-graphene hybrids. Scanning electron microscopy, X-ray diffraction, thermogravimetry analysis and Fourier transform infrared spectroscopy were employed to validate the preparation method. Results showed that the electrical conductivity of the hybrid samples decreased with increasing Fe3O4 loading. In addition, the magnetization measurements of the Fe3O4-graphene hybrids showed that they exhibit superparamagnetic effect at room temperature with MS values of up to 47.8 emu·g-1.