Enhanced microwave absorption characteristics of nanocomposite based on hollow carbonyl iron microspheres and polyaniline decorated with MWCNTs

This work presents the preparation of a novel lightweight microwave absorber nanocomposite based on a combination of hollow microspheres of iron carbonyl (CI) and polyaniline (PANI) decorated with MWCNTs by a simple blending technique. The weight ratio of hollow CI to PANI decorated with MWCNTs is 2:1. The morphology of the hollow CI microspheres-prepared by Pitting corrosion of CI powder immersed into corrosive solution at different concentrations and for different periods of time-was investigated by scanning electron microscope (SEM). The complex permittivity, permeability and microwave absorption properties of the composite are studied in the frequency range of 8.5-12.5 GHz with 30 wt% of composite in paraffin. The optimal reflection loss (RL) of −25.5 dB is observed at 11 GHz with a matching thickness of 2.0 mm and a bandwidth of 3.6 GHz.