Enhanced microwave electromagnetic properties of Fe3O4/graphene nanosheet composites

•Fe3O4/GNS nanoparticles have the significantly enhanced dielectric properties when compared with pure Fe3O4.•The absorbing bandwidth of Fe3O4/GNS composites exhibits more wider than pure Fe3O4.•The peak value of the reflection loss of Fe3O4/GNS composites has a tendency to be more lower with a thinner thickness.

Fe3O4/graphene nanosheet (Fe3O4/GNS) composites were prepared from acetylacetone iron (III) and graphene oxide (GO) with ethylene glycol (EG) as the solvent and reducing agent. The SEM and TEM images show that the Fe3O4 nanoparticles with relatively uniform size are well-distributed on the surface of graphene nanosheet. The structure guiding agents have a great influence on the size and surface property of Fe3O4 particles by control the nucleation and growth of Fe3O4. The effect of GNS in the composites was also discussed by regulation the mass ratio of acetylacetone iron (III) and GO. The optimal Fe3O4/GNS composites have significantly enhanced dielectric properties when compared with pure Fe3O4. Especially, it can be found that the calculated minimum RL for Fe3O4/GNS composites with a thickness of 1.5 mm is −8.75 dB at 8.11 GHz, the microwave absorption values less than −5 dB is in the ranges of 7.78–10.36 GHz, moreover, it can be modulated by tuning the mass ratio of Fe3O4 and GO. Therefore, the composites with the thin, light-weighted and broadband absorbing properties probably have a huge potential for electromagnetic wave absorption applications.

Graphical abstractThe calculated minimum RL for Fe3O4/GNS composites with a thickness of 1.5 mm is −8.75 dB at 8.11 GHz, the microwave absorption values less than −5 dB is in the ranges of 7.78–10.36 GHz, moreover, it can be modulated by tuning the mass ratio of Fe3O4 and GO.Figure optionsDownload full-size imageDownload as PowerPoint slide