Microstructure induced dielectric loss in lightweight Fe3O4 foam for electromagnetic wave absorption

Qing Chang; Hongsheng Liang; Bin Shi; Hongjing Wu

doi:10.1016/j.isci.2022.103925

Microstructure induced dielectric loss in lightweight Fe₃O₄ foam for electromagnetic wave absorption

iScience. 2022 Feb 14;25(3):103925. doi: 10.1016/j.isci.2022.103925. eCollection 2022 Mar 18.

Authors

Qing Chang^{1

2}, Hongsheng Liang¹, Bin Shi³, Hongjing Wu¹

Affiliations

¹ MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary, School of Physical Science and Technology, Northwestern Polytechnical University, Xi'an 710072, China.
² College of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yan'an University, Yan'an 716000, China.
³ Center for Translational Medicine Research on Sensory-Motor Diseases, Yan'an University, Yan'an 716000, China.

Abstract

Fe₃O₄ has been extensively applied in electromagnetic wave absorption field profiting from its advantageous magnetic loss, low cost and environmental benignity. Nevertheless, the inherent drawbacks of high density, low permittivity and easily magnetic aggregation are still the obstacles for pristine Fe₃O₄ becoming ideal absorbents. To overcome such limitations, a design mentality of constructing 3D structure shaped by curled 2D porous surface is proposed in this study. 3D structure overcomes the easy-agglomeration issue of 2D materials and meanwhile maintains their conductivity. The complex permittivity of samples is regulated by adjusting the microstructure of Fe₃O₄ to achieve optimum impedance matching. Defect induced polarization and interfacial polarization are the main loss mechanisms. Impressively, the density of S0.5 is only 0.05078 g/cm³ and the effective absorption bandwidth is up to 6.24 GHz (11.76-18 GHz) at 1.8 mm. This work provided a new insight for structurally improving the EMW absorption performance of pure magnetic materials.

Keywords: Electrodynamics; Physics.