Generation Mechanism of Negative Dielectric Properties of Metallic Oxide Crystals/Polyaniline Composites

Abstract

Inorganic particles/polyaniline (PANI) composite materials showed negative permittivity in recent years so that different conductive polymers filled with a wide variety of inorganic particles have been investigated for higher negative permittivity. However, the generation mechanism on negative dielectric properties of these inorganic particles/conductive polymers was still controversial. For this target, the generation mechanism of the negative dielectric properties of the metal oxide/PANI composite was studied in present study. Both PANI and Al 2 O 3 /PANI composites synthesized were found possessing negative permittivity. On the basis of structural analysis, the structure model of "crystal-nanowire" was constructed to explain the generation mechanism of negative permittivity of Al 2 O 3 /PANI composites. For further verifying the structure model, a variety of metal oxides were selected to prepare metal oxide/PANI composite materials. Negative dielectric effects were also found, proving the universality of this structure model to understand the generation mechanism of negative permittivity of Al 2 O 3 /PANI composites.

Flexible polydimethylsiloxane/multi-walled carbon nanotubes membranous metacomposites with negative permittivity

“…With the increase of frequency, the energy loss was gradually dominated by polarizing dipoles rather than the conduction electrons, so the permittivity exhibited the relaxation characteristic [44]. Similar phenomena were also observed in the Ni/epoxy composites [61] and current derived from the partial CNTs networks, the tanδ was not too large to hamper the impedance match, compared with that of previous study [63,64]. For the resultant composites with negative permittivity (shown in Fig.…”

Negative Permittivity Behavior in Silver/Polyaniline Metacomposites Induced by the Low-Frequency Plasmonic Oscillation

“…During the synthesis, adding different mass fractions (0, 10, 15, 30 and 40 wt%) of Ag nanowires to prepare Ag/PANI composites metacomposites. The detailed polymerization process of PANI matrix composites can refer to the reported literature [15].…”

Magnetic negative permittivity with dielectric resonance in random Fe3O4@graphene-phenolic resin composites

“…However, the transition of ɛ′ from positive to negative was observed when FGR content reached 91 vol% and the transition frequency was near 460 MHz. The appearance of negative permittivity from FGR91 might be attributed to a dielectric resonance which was called Lorentz model: [38][39][40][41][42][43] …”