Superior microwave absorbing cement-based composite using graphite flake / MnFe2O4 spinel ferrite nanoparticles

Abstract

In this study, graphite flake-cement (GFC) composite and MnFe2O4-cement (MFC) nanocomposite with desirable porous structures were developed. The microwave absorption performance of developed cement composites was investigated in the X-band frequency (8.2–12.4 GHz). The developed GFC composite displayed a minimum reflection loss of −19.3 dB (corresponding to 98.826 % electromagnetic wave absorption) at 9.7 GHz with a thickness of 7 mm and an effective absorption bandwidth (EAB) (at which the reflection loss reaches −10 dB) of 0.8 GHz. The MFC composite attained the minimum reflection loss of −44.5 dB (corresponding to 99.996 % EM wave absorption) at 11.7 GHz with a thickness of 7 mm and EAB of 1.3 GHz. The study suggests that adding conductive graphite flakes or MnFe2O4 spinel ferrite magnetic fillers into cement can provide efficient microwave absorption characteristics. The electromagnetic parameters, such as complex permittivity and permeability, dielectric loss, and magnetic loss, were also analyzed. In addition, the results of this study implied that the graphite flakes or MnFe2O4 nanoparticle-incorporated cement composite might be used to create buildings with greater resistance to electromagnetic radiation.