Multifunctional PVDF-BaTi0.95Zr0.05O3 composites: A synergistic approach to energy storage, energy harvesting, sensing, and UV-shielding

Abstract

Materials with versatile properties suitable for diverse applications are a major focus in contemporary research. Polymer-ceramic composites represent a promising class of materials, widely employed in capacitors, sensors, electrocaloric devices, optics, catalysis, and wastewater treatment. In this study, polyvinylidene fluoride-barium zirconium titanate (PVDF-BaTi0.95Zr0.05O3, abbreviated as PVDF-BZT5) composite films were fabricated by the solution casting method. BZT5 exhibited 90.63% orthorhombic and 9.37% tetragonal phases, with a piezoelectric charge coefficient (d33) of 164 pC/N at ambient temperature. X-ray diffraction (XRD) confirmed the successful formation of the composite films, revealing characteristic peaks corresponding to both PVDF and BZT5. The beta phase fraction of PVDF varied from 75 to 88% with increasing BZT5 weight percentage (wt%). Significant enhancements in dielectric constant, dielectric loss, piezovoltage, current, and power density were observed up to 40 wt% BZT5. Notably, remnant polarization (Pr), saturation polarization (PS), and coercive field (Ec) peaked at 20 wt% BZT5, delivering a maximum recoverable energy density (Wrec) of 103.3 mJ/cm3@250 kV/cm. Under an applied mechanical pressure of 154.32 kPa at a cyclic frequency of 5 Hz, PVDF-BZT5-40 film generated 26 V, 28nA, and 22.5 mu W/cm3. The generated voltage was sufficient to power six red light-emitting diodes (LEDs). Furthermore, the increased photon absorbance range and intensity with higher filler wt% demonstrated the composite films' potential for shielding the ultraviolet-visible (UV-vis) part of the electromagnetic radiation.