Enhanced functionalities in flexible poly (vinylidene fluoride-trifluoroethylene)/cerium oxide doped sodium bismuth titanate [P(VDF-TrFE)/NBT-CeO2] ceramic polymer composite films: A comprehensive investigation of piezoelectric, pyroelectric, and ferroelectric properties

Abstract

In the pursuit of innovative smart polymer piezoelectric ceramic composites, we present a thorough examination of the physical, structural, and polarization characteristics of a novel flexible polymer ceramic composite comprising sodium-bismuth titanate (NBT) doped with 0.6 mass % CeO₂ as ceramic fillers embedded in a poly (vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) polymer matrix. The incorporation of these fillers serves to increase both the mechanical strength and functional attributes of the resulting polymer-ceramic composites. Various volume percentages of ceramic fillers were employed, and the experimental effective dielectric permittivity results were systematically fitted to established theoretical models, including Maxwell, Clausius$-$Mossotti, Furukawa, and effective medium theory (EMT). Our findings reveal that the composite films exhibit exceptional piezo-, pyro-, and ferroelectric properties when compared to the pristine P(VDF-TrFE) copolymer. The optimum concentration of NBT-0.6 CeO₂ filler was determined to be 0.2 vol fraction resulting in a remarkable enhancement of the key parameters. Specifically, the pyroelectric coefficient increased from 32 μC/m²K to 43 μC/m²K (a ∼35 % increment), remnant polarization surged from 80 mC/m² to 166 mC/m² (an impressive ∼110 % increment), and the piezoelectric constant (d₃₃) elevated from −38 pC/N to 49 pC/N (a substantial ∼30 % increment). These findings signify the potential of these optimized samples for applications in high energy density capacitors and/or highly integrated and intelligent piezoelectric devices. This comprehensive investigation not only advances our understanding of the synergistic effects within polymer-ceramic composites but also underscores the potential of the proposed material system for practical applications, providing valuable insights for the development of advanced multifunctional materials.