Multilayer nano BaTiO3/poly (vinylidene fluoride) thin

Journal of Nanomaterials & Molecular Nanotechnology.ISSN: 2324-8777

All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.

Multilayer nano BaTiO3/poly (vinylidene fluoride) thin film with high energy density

Xiaohui Wang and Longtu Li

Tsinghua University, China
: J Nanomater Mol Nanotechnol


Organic-inorganic 0-3 nanocomposites, which combine the potentially high dielectric strength of the organic matrix and the high dielectric permittivity of the inorganic filler, are extensively studied as energy-storage dielectrics in high-performance capacitors. To obtain high dielectric constants, a large volume fraction of the inorganic component is necessary, but this will frequently deteriorate the dielectric (breakdown) strength and thus limit the energy density value of the overall nano-composite. In this study, a gradated multilayer BaTiO3/poly (vinylidene fluoride) thin film structure is presented as a means to achieve both higher breakdown strength and a superior energy-storage capability. Key to the process is the sequential deposition of uniform dispersions of the single component source, which generate a blended PVDF-BTO-PVDF structure prior to full evaporation of solvent and thermal treatment of the dielectric. The result is a 2-2 like sandwich structure with partial 0-3 character, seamless interfaces between layers and a concentration gradient of the BTO. The central layer designed to provide the high electric displacement, is composed of high volume fraction 6-10 nm BTO nanocrystals produced by a TEG-sol method. The outer layers of the structure are predominantly PVDF, with a significantly lower volume fraction of BTO, taking advantage of the higher dielectric strength for pure PVDF at the electrode-nanocomposite interface. The film is mechanically flexible, and can be removed from the substrate, with total thicknesses in the range 1.2-1.5μm. Parallel plate capacitance devices exhibit highly improved dielectric performances, compared to reported values for BTO-PVDF 0-3 nanocomposites, with low-frequency permittivity values of 20-25, a maximal discharged energy density of 19.4J/ cm3 and dielectric breakdown strengths up to 495kV/mm..



Track Your Manuscript