Preparation of rGO/PVA/CIP composites and their microwave absorption properties

Designing novel structure to optimize the dielectric constant and permeability was believed as an effective way to improve the performances of wave-absorbing material. In this work, PVA coating containing homogeneously distributed graphene oxide (GO) was firstly deposited onto the surface of carbonyl iron powder (CIP), which was then followed by a heat-treatment to obtain rGO/PVA/CIP composite materials. The electromagnetic parameters (relative complex permittivity and permeability) and corresponding loss mechanism of the as-prepared rGO/PVA/CIP composites were investigated in a frequency of 2.0-18.0 GHz. It was found that the presence of welldispersed rGO could effectively improve the dielectric loss of the composites and microwave absorption capability without sacrificing magnetic loss. The effective absorbing width (reflection loss lower than -10 dB) of PVA/CIP composite containing 1 mg/g GO was measured to be similar to 8.4 GHz.