Solvothermal synthesis and characterization of functionalized graphene sheets (FGSs)/magnetite hybrids

Novel functionalized graphene sheets (FGSs)/Fe3O4 hybrids were synthesized through a facile one-step solvothermal method using FeCl3 as iron source, ethylene glycol as the reducing agent and graphene nanosheets as templates. The morphology, composition and phase structure of as-prepared hybrid materials were characterized by scanning electron microscopy (SEM). X-ray photoelectron spectroscopy (XPS). X-ray diffraction (XRD), and transmission electron microscopy (TEM). These results showed that denseness, size and crystallinity of magnetite can be altered by controlling the reaction parameters. Magnetization measurement indicated that both coercivity and saturation magnetization increased linearly with increasing magnetite concentration in hybrid materials. The measured relative complex permittivity indicated that a high resistivity existed in the FGSs/Fe3O4 inorganic hybrids. The magnetic loss was caused mainly by ferromagnetic natural resonance, which is in agreement with the Kittel equation. The novel inorganic hybrid materials are believed to have potential applications in the microwave absorbing performances. (C) 2011 Elsevier B.V. All rights reserved.