Improved microwave absorption properties of ferrite-rGO composites by covalent bond

In this work, to investigate the effect of electron motion mode on the microwave absorption performance, ferrite Fe3O4 and graphene oxide (GO) were united by covalent bonding and subsequent reduction to fabricate microwave absorbing material (MAM) with excellent impedance matching characteristics and superb attenuation ability. Under the synergistic effect of the magnetic and dielectric properties, the Fe3O4-rGO hybrid nanocomposites present high absorption performance. Its minimum reflection loss (RLmin) reached -47.46 dB when the thickness was 3.5 mm. The effective absorption bandwidth (EAB) was 5.86 GHz when the thickness was only 2.0 mm. XPS and FT-IR spectroscopy indicate the formation of amide bonds between the modified Fe3O4 and functional GO. SEM, EDS, TEM and Raman spectroscopy were used to analyze the morphology and structure of the hybrid nanocomposites. The effects of bonding modes and component fractions on the electron motion and the resulting impedance matching of the hybrid nanocomposites were discussed.