Enhanced Performance of Piezoelectric Generator based on PVDF/ZnO/TiO2Composite Films for Energy Harvesting Applications

Abstract

The growing use of low-power electronic devices has highlighted the need for energy harvesting technologies that reduce dependence on conventional batteries. This work focuses on developing a piezoelectric energy generator incorporating poly vinylidene fluoride (PVDF) composite films with varying proportions (5 wt.%, 10 wt.% and 15 wt.%) of zinc oxide (ZnO) and fixed proportion (3 wt.%) of titanium dioxide (TiO₂) as dual fillers in various proportions. The composite films were characterized using techniques such as X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Piezoelectric measurements. XRD analysis confirmed the presence of wurtzite ZnO and anatase TiO₂ along with the electroactive β-phase of PVDF. FTIR measurements further verified the enhancement in β-phase of PVDF on progressively increasing the filler loading. Further microstructural analysis of pristine PVDF and doped composite films were analyzed using SEM, and EDS analysis verified the incorporation of ZnO and TiO₂ in the PVDF. When subjected to identical mechanical force, ZTP10 fabricated device shows the maximum output of Piezoelectric generators (PEGs) which increased from 11V for undoped PVDF to 206 V for the ZTP10 device (10 wt.% ZnO & 3 wt.% TiO₂), which is nearly 17.7 times increase in the open circuit voltage on incorporation of dual fillers ZnO and TiO₂. The practical applicability of ZTP10 device was demonstrated using various human motions, it produced 28.4 V on fist thumping, 18.4 V on finger tapping, 3.4 V on wrist bending, and by glowing LEDs when tapped by hand, confirming its use in self-powered devices.