Synthesis of CF@PANI hybrid nanocomposites decorated with Fe3O4 nanoparticles towards excellent lightweight microwave absorber

Recently, lightweight has gradually become the most concerned property for a practical microwave absorber in the frequency range of 2–18 GHz. In this work, using commercial carbon fiber (CF) as matrix, the hybrid nanocomposites constructed by CF core, polyaniline (PANI) coating and dispersed Fe3O4 nanoparticles (NPs) were successfully synthesized by the electrodeposition and subsequent hydrothermal process. The systematic characterization results revealed that both PANI and Fe3O4 exerted positive roles in enhancing the microwave absorption properties of bare CF. Under the combined action of various components, the desired products ([email protected]@Fe3O4 hybrid nanocomposites) exhibited remarkable microwave absorption performances, and the minimal reflection loss (RL) was −46.86 dB at a filler content of 10 wt% and a matching thickness of 2.7 mm. Moreover, a synergistic mechanism was proposed according to multiple reflection/scattering, dipole polarization, interface polarization, eddy current and magnetic resonance, so as to demonstrate the multi-attenuation approaches of the incident electromagnetic wave.