Waste-to-energy utilization by using a PVDF-based flexible piezoelectric nanogenerator for efficient energy harvesting applications†

Abstract

The rapid expansion of wearable, portable electronics has encouraged scientists to create flexible, self-powered gadgets with energy-harvesting capabilities. Here, we designed a PVDF composite-based flexible piezoelectric nanogenerator through stabilization of the polar beta phase of the PVDF polymer using fly ash, a hazardous waste product. We were able to stabilise the PVDF's β-phase without the need for external electrical polling by employing this filler. Negative surface charge of the fly ash facilitates the β-phase stabilization in PVDF by means of electrostatic contact. A flexible fly ash/PVDF composite using 15 wt% calcined fly ash was prepared using a low-cost solution casting technique. The fly ash can successfully stabilize the β-phase of the PVDF polymer up to ∼90%. The CFA/PVDF composite was subsequently moulded and positioned between the copper electrodes. Under a human finger pressure of around 20 kPa, the manufactured waste material-based piezoelectric nanogenerator (WPNG) can produce up to ∼27 V of voltage and 0.3 μA of current. In addition, the WPNG can generate a power density of 9.11 μW cm⁻² at a resistance of 10 MΩ, which is sufficient enough to power up other tiny devices like calculators, speakers, and wristwatches, as well as charge capacitors and illuminate LEDs. The fabricated nanogenerator shows almost the same output performance even after four weeks.