Hydrothermal self-assembled Fe3O4/CA core-shell composites for broadband microwave absorption

Electromagnetic wave has emerged as a new source of environmental pollution in the daily life. Therefore, the prominent microwave absorbents are urgently needed. In this work, the carbon aerogel and Fe3O4 nanoparticle (Fe3O4/CA) composites with core-shell structure were facilely prepared by a self-assembly process between carbon aerogels and Fe ion under the hydrothermal condition. The microwave absorption performance was significantly enhanced due to the perfect impedance matching and effective interface polarization. Compared with Fe3O4 nanoparticles and carbon aerogels, Fe3O4/CA composites show the advantages of strong microwave absorption and broad absorption bandwidth. The maximum RL value of Fe3O4/CA composites is up to -50.96 dB at 4.80 GHz. And also, the effective absorption bandwidth reaches 3.82 GHz with the thickness of 2 mm.