Silica-Coated BaTiO3/P(VDF-CTFE) Nanocomposites for Electrical Energy Storage

Open Access
Author:
Reainthippayasakul, Wuttichai
Graduate Program:
Materials Science and Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
October 27, 2014
Committee Members:
  • Qing Wang, Thesis Advisor
Keywords:
  • Nanocomposites
  • Barium Titanate
  • P(VDF-CTFE)
  • Energy Storage
Abstract:
The nanocomposites of ferroelectric polymers with ceramic nanoparticles are considered to be fascinating materials for electrical energy storage applications owing to the combination of their benefits. Ceramic nanofillers, like BaTiO3 nanoparticles, can offer high dielectric permittivity, while ferroelectric polymer, like poly(vinylidene fluoride-co-chlorotrifluoroethylene) or P(VDF-CTFE), can provide high breakdown strength, lightweight, good flexibility and processability. In order to improve the compatibility and energy storage properties of the nanocomposites, the surface modification of the nanoparticles is a crucial role. The core-shell particle/polymer nanocomposites consisting of silica-coated BaTiO3 (BT@SiO2) nanoparticles as dielectric fillers and P(VDF-CTFE) as ferroelectric polymer matrix could be successfully fabricated by solution casting method. The BT@SiO2/P(VDF-CTFE) nanocomposites clearly exhibit improved dielectric properties and electrical breakdown strength compared to the pristine polymer and the nanocomposites with unmodified BT nanoparticles. The enhancement in dielectric properties of the nanocomposites is attributed to the introduction of BaTiO3 nanoparticles, whereas the improvement of breakdown field has been rationalized on the effects of insulating silica shells by increasing the electrical resistivity and mechanical strength of the materials. These developments confirm that the nanocomposites of ferroelectric polymers with silica-coated nanoparticles can be decent materials for energy storage devices.