Novel three-component nanocomposites with high dielectric permittivity and low dielectric loss co-filled by carboxyl-functionalized multi-walled nanotube and BaTiO3

In this work, a novel ternary polydimethylsiloxane (PDMS)-based nanocomposite co-filled by carboxyl-functionalized multi-walled nanotube (cMWCNT) and BaTiO3(BT) nanoparticle were developed. The hybrids cMWCNT-BT was realized via the hydrogen bonding (H-bonding) interaction between -COOH groups of cMWCNT and the -OH groups of BT. Compared with the binary composite of BT/PDMS and cMWCNT/PDMS, the results showed that the kind of three-component nanocomposites had high dielectric permittivity and low dielectric loss. Different from cMWCNT, the hybrids cMWCNT-BT have good dispersion in PDMS matrix, forming many micro-capacitors and interfaces, and thus leading to remarkably high dielectric constant. Meanwhile, BT on the surfaces of cMWCNT reduce the direct contact of cMWCNT, resulting in reduced dielectric loss. More important, the BT and cMWCNT had a synergistic effect on dielectric permittivity of the cMWCNT-BT/PDMS composite. Therefore, the dielectric properties of the novel ternary composite can be improved by optimizing the synergistic effects between the charge storage behavior of the ferroelectric phase and the charge transport behavior of the conductive phase.