Preparation of reduced graphene oxide/Fe3O4 nanocomposite and its microwave electromagnetic properties

The reduced graphene oxide (r-GO) coated with Fe3O4 composite was synthesized through a facile method involving decomposition of Fe(OH)3 in argon atmosphere and reduction in hydrogen and argon mixture atmosphere. The Fe3O4 particles evenly distributed on r-GO, with the diameters from 10 nm to 40 nm, are monocrystalline. The composite demonstrates a reflection loss below −10 dB in 14.3–18 GHz range, and the maximum absorption of −22.2 dB at 17.3 GHz. The microwave absorption of r-GO/Fe3O4 nanocomposites is attributed to relaxation and polarization of the residual groups and defect of graphene and polarization attributed to the presence of Fe2+ ions in Fe3O4.

► The reduced graphene oxide (r-GO) coated with Fe3O4 composite was synthesized.
► The Fe3O4 particles are evenly distributed on r-GO.
► The composite has a reflection loss below −10 dB at 14.3–18 GHz.