Study of β-phase, dielectric and ferroelectric properties of graphene oxide-reinforced poly[(vinylidene fluoride)-co-trifluoroethylene]-based three-phase composite films for energy storage applications

Electrical storage continues to be a vital domain which contributes to more efficient, reliable and sustainable energy systems to meet the ever-growing demand for useable electrical energy. In recent years, the benefits of excellent mechanical and dielectric performance have led to a significant increase in interest in polymer-based composites for capacitive energy storage applications. Here, poly[(vinylidene fluoride)-co-trifluoroethylene]/0.5(BaZr_0.2Ti_0.8O)₃–0.5(Ba_0.7Ca_0.3TiO)₃/graphene oxide (PVDF-TrFE/BZT-BCT/GO) three-phase composite films were prepared via solvent casting followed by a hot-pressing method. X-ray diffraction and Fourier transform infrared and Raman spectroscopies were performed for structural confirmation of the composites. Dielectric study showed a maximum relative permittivity of 19.35 at 1 kHz, which is around 65% of that of pure PVDF-TrFE film. Static hysteresis loops were traced for all the samples, showing a maximum efficiency of 89.33% for a composite film. Positive up negative down measurements were also done to confirm the data obtained from static hysteresis analysis. Furthermore, the electromechanical coupling coefficient was analyzed using the resonance–antiresonance method, which gives an insight into the electromechanical properties in the synthesized films. The synthesized three-phase composites can therefore find application for piezoelectric purposes along with capacitive energy storage. © 2025 Society of Chemical Industry.