Biomass-derived porous carbon combined with CoFe₂O₄/CoFe@C for available low-frequency microwave dissipation

For defusing the low-frequency microwave radiation contamination, herein, a group of BPC-CoFe₂O₄/CoFe@C composites were obtained by regulating the bio-based porous carbon with two different routes, solvothermal loading of magnetic particles and subsequent annealing treatment. The investigation reveals the technical parameters have great effect on the microwave absorption mechanism of prepared absorbents, in which the APC-700 possesses excellent impedance matching characteristic within a wide low-frequency range, and integrated with multi-level polarization, eddy current loss of magnetic alloy, natural resonance of ferrite, electron hopping and conduction loss, and structural dissipation with special porous morphology, it can achieve broad low-frequency EAB of 2.15 GHz at only 1.5 mm, with a maximal RL of −39.48 dB at 1.22 GHz for 2 mm. This forebodes the potential application of composite prepared here to solve the mentioned low-frequency radiation contamination.