Combining carbon nanotube foam with nanosilver/silicone resin or graphene foam for advanced metamaterial design

摘要

Advanced metamaterials are designed upon the combination of (1) carbon nanotube (CNT) foam, which is obtained from chemical vapor deposition by fully consuming the initial nickel foam, and (2) nanosilver/silicone resin or graphene (Gr) foam. The CNT foam/nanosilver/silicone composite simultaneously exhibits a negative permittivity and permeability in the frequency range from 1 MHz to 1 GHz provided that the appropriate CNT foam amount is considered (20 m%). Double-negative performance in a similar frequency range is obtained with both 3/1 and 1/1 (mass basis) Gr/CNT-based composites. On the other hand, 3/2 (mass basis) Gr/CNT exhibits a negative permeability in the shared frequency range from 6 x 10(2) MHz to 1 GHz with still negative permittivity in the full range. The Gr amount allows to control the frequency behavior, with a variation in absolute permittivity and permeability values and a switch between a concave and convex behavior. Hence, the work contributes to the further expanding of the application range of metamaterials.