Power enhancement of piezoelectric energy harvester using ZnOnf-PDMS composite with PVDF filler

This work aims to fabricate a piezoelectric energy harvester using Polydimethylsiloxane (PDMS) with Zinc Oxide nanoflower (ZnOnf) and Poly(vinylidene fluoride) (PVDF). ZnOnf is synthesised via the hydrothermal method by varying the reaction time. The long nanoflowers resulting from the reaction time of 2 h are utilized to prepare the piezoelectric composite. Two energy harvesters are fabricated: ZnOnf-PDMS (ZP) and ZnOnf-PVDF-PDMS (ZPP), to harvest mechanical energy. The incorporation of PVDF into the ZnOnf-PDMS composite enhances the active polar β-phase of PVDF, leading to improved piezoelectric activity. The output voltage of the piezoelectric harvesters is measured under various impact forces applied using a self-designed impact force setup. The addition of PVDF to the ZnOnf-PDMS composite results in an increase in the dielectric constant and, consequently, in the energy harvester's output. Thus, at an applied impact force of 2.64 N, the output power harvested is 11.4 µW for ZP, and is amplified to 14.27 µW for ZPP. Furthermore, the incorporation of PVDF enhances the thermal stability and delays the decomposition temperature of the energy harvester.