Plasma Oscillation Behavior and Electromagnetic Interference Shielding of Carbon Nanofibers/Conductive Polymer Metacomposites at Radarwave Frequency.

Metacomposites have attracted widespread attention due to their unique negative electromagnetic properties and stupendous applications. Although there are systems that realize metamaterial properties in low radio frequency bands, the research on the construction of polymer matrix metacomposites with negative performance in the pivotal GHz band is still undiscovered. Herein, carbon nanofiber/conductive polymer metacomposites with 3D overlapping network structures are innovatively constructed to achieve negative permittivity characteristics in the radarwave frequency range, and convenient methods for further adjusting the electromagnetic parameters is also proposed. The results show that the negative permittivity of CNFs/PANI metacomposites can be conveniently altered via adjusting PANI content. Furthermore, electromagnetic shielding has also been fully discussed as one of the most valuable applications of the metacomposites. The SE of CNFs/PANI-70 has an average value of 70 dB at 4-18 GHz and can reach a maximum of 80 dB at 4 GHz, which far exceeds the current commercial electromagnetic shielding standards. This work greatly broadens the promising application of metacomposites for perfect electromagnetic shielding, novel capacitance, and frequency selective surfaces.