Communication—Tunable and Weakly Negative Permittivity in CNTs-CBs/Polystyrene Metacomposites

The CNTs-CBs nano-units composed of carbon nanotubes (CNTs) and carbon black (CBs) have been prepared by electrostatic self-assembly. Herein, the CNTs-CBs/PS composites with different CNTs-CBs contents were prepared. The negative permittivity behavior was observed when three-dimensional conductive network was constructed by CNTs-CBs. Tunable and weakly negative permittivity originated from the low frequency plasmonic state which was collective electrons oscillation in CNTs-CBs network. The Jonscher's power law and Drude model were used to analyze the dielectric behavior and conductive mechanism changing. This work has broadened the applications of carbonaceous materials and polymers in the field of metamaterials.