High dielectric constant and low loss of polymeric dielectric composites filled by carbon nanotubes adhering BaTiO₃ hybrid particles

We reported the preparation of carbon nanotubes adhering BaTiO₃ nanoparticles (BT@CNTs) via chemical vapor deposition (CVD). Scanning electron microscopy, transmission electron microscope and Raman spectroscopy were carried out in order to confirm the successful adhesion. Dielectric properties of the PVDF-HFP composites filled by BT@CNTs were also studied. With the content of BT@CNTs increasing, the dielectric constant of composites remarkably increased, but the loss tangent gradually decreased. At 10 vol%, the dielectric constant of the PVDF-HFP/BT@CNTs composite was significantly increased to 27.7 at 50 Hz, which was 3 times and 65% higher than that of the pure PVDF-HFP and PVDF-HFP/BT composite, respectively. The loss tangent of the PVDF-HFP/BT@CNTs composite was lower even than that of pure PVDF-HFP. These attractive features of the PVDF-HFP/BT@CNTs composites suggested that the method proposed herein was a new approach to develop high performance composites, especially those with high dielectric constant and low dielectric loss.