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Title: Ultrahigh Capacitive Energy Density in Stratified 2D Nanofiller-Based Polymer Dielectric Films
Dielectric capacitors are critical components in electronics and energy storage devices. The polymer-based dielectric capacitors have the advantages of device flexibility, fast charge–discharge rates, low loss, and graceful failure. Elevating the use of polymeric dielectric capacitors for advanced energy applications such as electric vehicles (EVs), however, requires significant enhancement of their energy densities. Here, we report a polymer thin film heterostructure-based capacitor of poly(vinylidene fluoride)/poly(methyl methacrylate) with stratified 2D nanofillers (Mica or h-BN nanosheets) (PVDF/PMMA-2D fillers/PVDF), that shows enhanced permittivity, high dielectric strength, and an ultrahigh energy density of ≈75 J/cm3 with efficiency over 79%. Density functional theory calculations verify the observed permittivity enhancement. This approach of using oriented 2D nanofillers-based polymer heterostructure composites is expected to be versatile for designing high energy density thin film polymeric dielectric capacitors for myriads of applications.  more » « less
Award ID(s):
1900692
PAR ID:
10470839
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American chemical society
Date Published:
Journal Name:
ACS Nano
Volume:
17
Issue:
20
ISSN:
1936-0851
Page Range / eLocation ID:
20262 to 20272
Subject(s) / Keyword(s):
polymer nanocomposite, dielectric capacitors, 2D nanofillers, dielectric constant, high energy density, high breakdown strength, high power density
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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