abstract
In the era of unprecedented advancement of portable electronics, the utilization of multifunctional materials that enable integration of functionalities, hold great promise since they not only reduce size and weight but also curtail energy consumption of the system. In this regard, this study focused on the development of polyvinylidene fluoride (PVDF)-based polymer composites and achieved excellent piezoelectric performance along with enhanced dielectric, ferroelectric and electrocaloric response. Novel flexible polymer composite films composed of P(VDF-TrFE) 55/45 polymer and BT-BMT (BaTiO3-0.2Bi(Mg0.5Ti0.5)O-3) oxide filler particles were fabricated using cost-effective solution-casting method. The inclusion of BT-BMT fillers promoted ferroelectric beta-phase formation, confirmed by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) and Raman spectroscopy studies. The dielectric permittivity enhanced considerably with the incorporation of filler particles, while the dielectric loss remained low. An excellent piezoelectric coefficient, vertical bar d(33)vertical bar similar to 41 pC/N was achieved in the optimal composite (5 wt% BT-BMT), which was nearly 58 % higher than that obtained in the pure copolymer (vertical bar d(33)vertical bar similar to 26 pC/N). Furthermore, an improved electrocaloric performance in terms of electrocaloric temperature change (Delta T) and electrocaloric strength was noted. A Delta T similar to 3.15 degrees C was achieved in the optimal composite film at a modest electric field of 60 MV/m. Additionally, the investigation of microscale piezoelectric and mechanical responses revealed a correlation with the macroscale properties and suggested a complex interplay of interphase effects (filler-polymer interface; crystalline-amorphous interface) in the films. Thus, this work highlights the significance of the BT-BMT fillers in enhancing prominent functional properties in the P(VDF-TrFE)/BT-BMT polymer composite films, thereby rendering them suitable for multifunctional flexible devices.
keywords
FERROELECTRIC PHASE-TRANSITION; DIELECTRIC-RELAXATION BEHAVIOR; POLY(VINYLIDENE FLUORIDE); VINYLIDENE FLUORIDE; NANOCRYSTALLINE BATIO3; MOLECULAR-DYNAMICS; STRUCTURAL-CHANGES; RAMAN-SCATTERING; ENERGY DENSITY; GAMMA PHASES
subject category
Engineering
authors
Coondoo, I; Isfahani, VB; Amorín, H; Bdikin, I; Carvalho, J; Pascual-González, C; Silva, BM; Oliveira, J; Pukazhselvan, D; Almeida, BG; Miranda, G
our authors
Georgina Miranda
Associate Professor with Habilitation
Indrani Coondoo
Junior ResearcherProjects
Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
Electric-Field Engineered Lattice Distortions (E-FiELD) for optoelectronic devices (E-FiELD)
acknowledgements
I. Coondoo and G. Miranda gratefully acknowledge support through the FCT project "MultiFlex" EXPL/CTM-CTM/0687/2021 (https://doi. org/10.54499/EXPL/CTM-CTM/0687/2021) . The author, I. Coondoo would also like to acknowledge financial assistance by national funds (OE) , through FCT - Fundacaopara a Ciencia e a Tecnologia, I.P., through DL57/2016/CP1482/CT0048 (https://doi.org/10.54499/DL57/2016/CP1482/CT0048) . This work was partially developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC) . V. B. Isfahani thank FCT for the grant from the project EXPL/CTM-CTM/0687/2021 and for her contract supported from the project with the reference UIDP/04968/2020. V. B. Isfahani also thank the support of Portuguese Foundation for Science and Technology (FCT) and IFIMUP, Portugal with the projects UIDB/04968/2020, UIDP/04968/2020 and LA/P/0095/2020 (Associate Laboratory, Laboratory of Physics for Materials and Emergent Technologies (LaPMET) ) . H. Amorin acknowledges the support through grants PID2021-122708OB-C33 and TED2021-130871B-C21 funded by MCIN/AEI/10.13039/501100011033 and, as appropriate, by ERDF A way of making Europe, and by the "European Union NextGeneration EU/PRTR". The support of Fundacao para a Cie ncia e Tecnologia through FEDER (European Fund for Regional Development) -COMPETE-QREN-EU (ref. UID/FIS/04650/2013 and UID/FIS/04650/2019) ; E-Field-"Electric-Field Engineered Lattice Distortions (E-FiELD) for optoelectronic devices", ref.: PTDC/NAN-MAT/0098/2020 and "Non-linear phononics: Manipulating the hidden quantum phases and dynamical multiferroicity", Ref. 2022.03564. PTDC, is acknowledged. B. M. Silva, J. Oliveira and J. Carvalho acknowledge their Ph.D. grants from FCT, with references 2021.07277. BD, SFRH/BD/146886/2019 and 2024.00842.BD, respectively. We thank Ms. Phalguni Coondoo for the 3D illustrations.