Graphene-Fe3O4 nanohybrids: Synthesis and excellent electromagnetic absorption properties

Graphene (G)-Fe3O4 nanohybrids were fabricated by first depositing beta-FeOOH crystals with diameter of 3-5 nm on the surface of the graphene sheets. After annealing under Ar flow, beta-FeOOH nanocrystals were reduced to Fe3O4 nanoparticles by the graphene sheets, and thus G-Fe3O4 nanohybrids were obtained. The Fe3O4 nanoparticles with a diameter of about 25 nm were uniformly dispersed over the surface of the graphene sheets. Moreover, compared with other magnetic materials and the graphene, the nanohybrids exhibited significantly increased electromagnetic absorption properties owing to high surface areas, interfacial polarizations, and good separation of magnetic nanoparticles. The maximum reflection loss was up to -40.36 dB for G-Fe3O4 nanohybrids with a thickness of 5.0mm. The nanohybrids are very promising for lightweight and strong electromagnetic attenuation materials. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4774243]