1 research outputs found
Elucidating the Piezoelectric, Ferroelectric, and Dielectric Performance of Lead-Free KNN/PVDF and Its Copolymer-Based Flexible Composite Films
Ecofriendly, reliable, and high-performance piezoelectric
materials
are drawing huge interest in resolving the environmental problems
arising due to consumption of fossil fuel energy. Among the lead-free
ferroelectrics, potassium sodium niobate (KNN, (K,Na)NbO3) is one of the most promising piezoelectric ceramics that can replace
Pb(Zr,Ti)O3. In the present work, the piezoelectric performance
of KNN incorporated in poly(vinylidene fluoride) (PVDF) and its copolymers,
polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) and poly(vinylidene
fluoride-hexafluoropropylene) (PVDF-HFP), has been compared. The films
were fabricated by a solution casting method and were further polarized
by a corona poling technique. The results confirmed that the nanocomposite
film with 8 wt % KNN filler in PVDF-TrFE (PTK8) exhibited the highest F(β) value, maximum remnant polarization, and dielectric
constant value than other nanocomposites. The relative β-phase
contents in PTK8, PHK8, and PK8 composite films reached 85, 76, and
75.8%, respectively, indicating that KNN acts as the most suitable
nucleating agent in PVDF-TrFE. Also, the piezoelectric voltage output
of the PTK8-based nanogenerator was found to be remarkably higher
(∼20 V) as compared to other nanocomposite-based piezoelectric
nanogenerators. It also exhibited a maximum power density of 0.54
μW/cm2 that was significantly improved in comparison
to other composites. This nanogenerator was found to be a promising
power generation device promoting miniaturization of self-powered
systems