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Not AvailableThe demand for energy storage devices with high energy density, power density, and higher efficiencies has motivated researchers to explore novel materials and designs beyond current limitations. Polymer-based dielectric capacitors are flexible, lightweight, self-healable, and compatible with a variety of nanofillers. Despite a plethora of studies on polymer nanocomposites with 2D nanofillers, the role of multilayered 2D nanofillers in polymer nanocomposites in the context of energy storage properties has yet to be determined. In this work, mechanically exfoliated 2D mica nanofillers were incorporated with poly(vinylidene fluoride) (PVDF) polymer to fabricate PVDF-mica-PVDF (PMP) multilayered heterostructure capacitors. A single exfoliated layer of mica with an average thickness of the flakes of 20 nm interfaced within layers of PVDF to form PMP and using two layers of mica to form PVDF/mica/PVDF/mica/PVDF (PMPMP) heterostructure capacitors. Average enhancements of 100% and 170% were measured for the dielectric constants of PMP (εav ∼ 22.9) and PMPMP (εav ∼ 30.8), respectively compared to that of the pristine PVDF (εav ∼ 11.4) films measured using the same setup. The highest discharged energy density of PMP and PMPMP nanocomposite films reached 27.5 J/cm3 (E = 670 MV/m) and 44 J/cm3 (E = 570 MV/m), compared to 11.2 J/cm3 (E = 396 MV/m) for the pristine PVDF capacitor. This work develops a detailed understanding of the use of multilayered 2D nanofillers to develop high-capacitance and high energy density polymeric dielectric capacitors and opens avenues for developing orientation-controlled 2D nanofiller-based capacitors for use in industrial applications.
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Gd5Si4-PVDF nanocomposite films and their potential for triboelectric energy harvesting applications
The triboelectric energy generators prepared using the combination of self-polarized, high β-phase nanocomposite films of Gd5Si4-PVDF and polyamide-6 (PA-6) films have generated significantly higher voltage of ∼425 V, short-circuit current density of ∼30 mA/m2 and a charge density of ∼116.7 μC/m2 as compared to corresponding values of ∼300 V, 30 mA/m2 and 94.7 μC/m2, respectively for the pristine PVDF-(PA-6) combination. The magnetic measurements of the Gd5Si4-PVDF films display a ferromagnetic behavior as compared to diamagnetic nature of pristine PVDF. The presence of magnetic nanoparticles in the polymeric matrix allows for some control over the microstructural properties during the preparation process. The results open new routes for multiferroic composite films to be suitable for multi-functional magnetic and triboelectric energy harvesting applications.
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- Award ID(s):
- 1726617
- PAR ID:
- 10597429
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- AIP Advances
- Volume:
- 9
- Issue:
- 3
- ISSN:
- 2158-3226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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