Preparation, characterization and microwave absorbing properties of carbon coated carbonyl iron nanostructure

In this study, the carbonyl iron was coated with carbon via hydrothermal reaction and the microwave absorption properties of the carbon coated carbonyl iron nanostructure (CI/C) was investigated in the range of 8.2-12.4GHz. The structure, characterization and magnetic performances of the prepared nanostructures were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM).The microwave properties including complex permittivity (εr), the permeability (μr), dielectric loss, magnetic loss, reflection loss, and attenuation constant were investigated using a vector network analyzer. For CI particles the optimal reflection loss for 4.4 mm thickness was -16.86 dB at the matching frequency of 12.3 GHz. The bandwidth with RL more than -10 dB can be reached in the frequency range of 10.8–12.4 GHz and there was no RL values below -20 dB. While for The CI/C nanostructure, the bandwidth of below-10 dB (90% power absorption) and -20dB (99% power absorption) can be obtained in the frequency range of 9.8–12.4 GHz and 11.0-11.8GHz respectively, As well as, the optimal RL was -46.69 dB at the matching frequency of 11.5GHz, when the matching thickness is 1.3 mm. The results indicate that the existence layer of C coated on CI, enhances the electromagnetic absorbing properties.

Keywords:

Carbon coated carbonyl iron nanostructure , Microwave absorption properties , Hydrothermal reaction , Reflection loss