Core-shell structured BaTiO₃@carbon hybrid particles for polymer composites with enhanced dielectric performance

Core-shell structured BaTiO₃@carbon (BT@C) hybrid particles were fabricated via chemical vapor deposition (CVD). Scanning electron microscopy, transmission electron microscopy, X-ray diffraction and Raman spectroscopy were carried out to confirm the successful fabrication. In order to research the effect of BT@C hybrid particles on the dielectric performance of polymer composites, PVDF-HFP/BT@C composites were prepared. With the increase of the volume fraction of BT@C, the dielectric constant of composites remarkably increased. The dielectric constant of the composite with 30 vol% BT@C is 1044 at 1 kHz, which is 118 times higher than that of PVDF-HFP (8.8). The experimental results fit well with the percolation theory. The energy storage density of all composites is larger than that of pure PVDF-HFP. The influence of the carbon-shell on the dielectric properties of composites is discussed and analyzed. The enhanced dielectric properties are attributed to the increased interfacial polarization in the carbon-shell. These attractive fabrication methods of BT@C and features of PVDF-HFP/BT@C composites suggest that the method proposed herein is a new approach for developing high performance composites.