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Polyvinylidene difluoride trifluoroethylene (PVDF-TrFE) has received widespread application in flexible electronics and biomedical devices but is limited in its sensing modalities to piezoelectricity and pyroelectricity. The addition of optically or magnetically active nanoparticles could provide additional sensing modalities in the same element, which could drive miniaturization of such sensors. Europium barium titanate (EBTO) is one such optically active nanoparticle that could add functionality to such a nanocomposite. In this work, multifunctional nanocomposites of PVDF-TrFE and EBTO are successfully synthesized and characterized for their material and electronic properties. The nanocomposite in this work is the first known multifunctional nanocomposite with PVDF-TrFE and a fluorescent nanoparticle.
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Fabrication and magnetoelectric investigation of flexible PVDF-TrFE/cobalt ferrite nanocomposite films
Abstract Flexible nanocomposite films, with cobalt ferrite nanoparticles (CFN) as the ferromagnetic component and polyvinylidene fluoride–trifluoroethylene (PVDF-TrFE) copolymer as the ferroelectric matrix, were fabricated using a blade coating technique. Nanocomposite films were prepared using a two-step process; the first process involves the synthesis of cobalt ferrite (CoFe2O4) nanoparticles using a sonochemical method, and then incorporation of various weight percentages (0, 2.5, 5, and 10%) of cobalt ferrite nanoparticles into the PVDF-TrFE to form nanocomposites. The ferroelectric polarβphase of PVDF-TrFE was confirmed by x-ray diffraction (XRD). Thermal studies of films showed notable improvement in the thermal properties of the nanocomposite films with the incorporation of nanoparticles. The ferroelectric properties of the pure polymer/composite films were studied, showing a significant improvement of maximum polarization upon 5wt% CFN loading in PVDF-TrFE composite films compared to the PVDF-TrFE film. The magnetic properties of as-synthesized CFN and the polymer nanocomposites were studied, showing a magnetic saturation of 53.7 emu g−1at room temperature, while 10% cobalt ferrite-(PVDF-TrFE) nanocomposite shows 27.6 emu/g. We also describe a process for fabricating high optical quality pure PVDF-TrFE and pinhole-free nanocomposite films. Finally, the mechanical studies revealed that the mechanical strength of the films increases up to 5 wt% loading of the nanoparticles in the copolymer matrix and then decreases. This signifies that the obtained films could be suited for flexible electronics.
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- Award ID(s):
- 1827690
- PAR ID:
- 10365644
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Materials Research Express
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2053-1591
- Page Range / eLocation ID:
- Article No. 046302
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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