Large-scale solvent-thermal synthesis of graphene/magnetite/conductive oligomer ternary composites for microwave absorption

Nanocomposites exhibiting high electric conductivity and high saturation magnetization were synthesized in bulk using a solvent-thermal route, which combined the hybridization growth of Fe3O4 nanoparticles, graphene oxide, and a conductive oligomer in one step. The hybrid spheres with diameters of 100–300 nm (mostly approximately 200 nm) consisted of a homogenous phase without obvious interfaces between the ternary components. The electric conductivity of the hybrid material was greatly improved after heat treatment at high temperature. Because of the interfacial polarization and good separation property due to its magnetism properties, the interpenetrating nature of the materials yielded good synergistic effects on the electromagnetic wave absorbing properties. The multi-frequency reflection band covering the C band and Ku band with a maximum reflection loss of −45 dB for a thickness of 5 mm is promising for lightweight and strong electromagnetic attenuation applications.