Iron cobalt/polypyrrole nanoplates with tunable broadband electromagnetic wave absorption

Magnetic nanoparticles (NPs)/conducting polymer nanoplates are great potential candidates for advanced electromagnetic wave absorbents due to their unique physical properties such as strong absorption, low density and good anti-oxidation. In this work, iron cobalt nanoparticles (FeCo NPs) were prepared by a modified chemical reduction method and FeCo/polypyrrole (PPy) nanoplates were synthesized by in situ chemical oxidative polymerization. The nanoplates exhibited an excellent electromagnetic wave absorbing performance. The maximum reflection loss (RL) reaches -52.30 dB at 13.40 GHz with an absorber thickness of 2.15 mm and the effective absorbing width (RL < -10 dB) is located at approximately 11.31-16.37 GHz. The dipole polarization, interface polarization and space-charge polarization of the nanocomposites contribute to the dielectric loss of the electromagnetic wave. Moreover, the natural resonance, exchange resonance and eddy current loss of the nanocomposites contribute to the magnetic loss of the electromagnetic wave. The synergetic effect of both the dielectric and magnetic losses of the nanocomposites endows the FeCo/PPy nanoplates with excellent broadband electromagnetic wave absorption.