Dielectric-magnetic synergistic construction of 2D FeCo/Co8FeS8/C composites for efficient electromagnetic wave capture

Abstract

Nowadays, the issue of electromagnetic pollution has become increasingly prominent, underscoring the critical importance of developing high-performance microwave absorbers. This study put forwards the synthesis process of two-dimensional (2D) FeCo/Co8FeS8/C carbon nanosheets, wherein CoSO4 and FeCl3 serve as inorganic salt templates, and dopamine functions as the carbon source. FeCo alloy nanoparticles and Co8FeS8 nanoparticles are loaded on the surface of the carbon layer. 2D structure forms the conductive network, which proves advantages in establishing efficient electronic channels and minimizing conduction losses. The carbon component increases the dielectric constant of the composite and improves its impedance matching, and the FeCo alloy provides a certain ML. The synergistic effect between these components significantly contributes to the exceptional microwave absorption performance of the composites. Accordingly, the minimum reflection loss (RLmin) of FeCo/Co8FeS8/C composite reaches −47.4 dB, its effective absorption bandwidth (EAB) reaches 5.3 GHz. In particular, CST confirms that radar cross-section reduction value of FeCo/Co8FeS8/C composite can reach 20.2 dB m2 in the range of −90° < phi< 90°, indicating a high microwave attenuation ability. The study introduces a novel strategy for advancing the development of two-dimensional carbon-based absorption materials.