A novel rGO-ZnFe2O4 hollow microsphere composite with excellent microwave absorption properties

Abstract

In order to develop lightweight, efficient and broadband microwave absorbing materials, rGO-ZnFe2O4 hollow microsphere composites were prepared by the solution method in this paper. The effects of reduced graphene oxide (rGO) content on the microstructure of hollow microspheres and the microwave absorption properties of the material were studied. rGO micropowders and ZnFe2O4(ZFO) particles are uniformly distributed on the hollow microspheres. The rich porous hollow structure is conducive to the multiple reflection and scattering of electromagnetic microwaves. This structure and distribution state enable the composite material to have good impedance and form a synergistic effect of multiple absorption effects. The results show that the minimum reflection loss (RLmin) is −28.83 dB and the effective absorption bandwidth(EAB) is 5.92 GHz (11.04∼16.96 GHz) when the thickness is 2.00 mm and the rGO is 6.3 wt.%. The Radar scattering cross section(RCS) results show that the RCS values of the samples with the rGO is 6.3 wt.% are mostly below −20 dBm2 in the range of microwave incidence angle of −90°< Theta < 90°, which indicates the composites has wide-angle microwave absorption ability. This study provides a new approach to the design and preparation of efficient and lightweight electromagnetic microwave absorbing materials.