Affiliation:
1. State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
2. College of Science, National University of Defense Technology, Changsha 410073, China
Abstract
The low energy density (Ud) of polymeric dielectrics is unfavorable for the integration and miniaturization of electronics, thus limiting their application prospects. Introducing high-εr (dielectric constant) ceramic nanofillers to polymer matrices is the most common strategy to enhance their εr, and hence their Ud. By comparison, enhancing breakdown strength (Eb) is a more effective strategy to enhance Ud. Herein, 0.6BaTiO3-0.4Bi(Mg0.5Ti0.5)O3 and 0.85BaTiO3-0.15Bi(Mg0.5Zr0.5)O3 nanofibers coated with SiO2 were utilized as fillers in PVDF-based nanocomposites. The combination of experimental and simulation results suggests that the intrinsic properties of nanofillers are the determining factor of the Eb of polymer-based nanocomposites, and SiO2 coating and film structure design are effective strategies to enhance their Eb, and consequently their Ud. As a result, the sandwich-structured PVDF/6 wt% 0.85BaTiO3-0.15Bi(Mg0.5Zr0.5)O3@SiO2 nanofiber within PVDF/PVDF nanocomposite films achieved a maximum Ud of 11.1 J/cm3 at an Eb of 458 MV/m, which are 2.15 and 1.40 times those of pristine PVDF, respectively.
Funder
the Science and Technology Innovation Program of Hunan Province