High-Performance PVA/Graphene Oxide Composite for Cost-Effective and Sustainable Piezoelectric Energy Harvesting

Abstract

This study explores the piezoelectric generator prototype, utilizing the PVA and graphene oxide composite for the first time, demonstrating superior energy conversion efficiency and power output under various mechanical stimuli, such as vibrations and pressure fluctuations. Graphene oxide and nanosheets were extracted by intercalating a 1 M HNO₃ solvent into the graphitic layers. This process involved applying a voltage bias of 2 V DC for 5 min, followed by increasing the voltage to 6 V DC for 5 h. Graphene oxide is identified via X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–VIS), and Fourier transform infrared spectroscopy (FTIR). PVA typically peaks at around 2θ = 19.9°, which is the (101) plane. The direct energy bandgaps of the produced composite PVA/GO at 1 wt.% and 2 wt.% are 3.681 eV and 3.231 eV, respectively. FTIR spectra analysis of the PVA/graphene oxide composite reveals characteristic peaks from both components, indicating successful incorporation. The fabricated device, featuring a sandwich structure, exhibits superior performance with an impressive output voltage of approximately 15 Vpp. This device could be very effective in energy-harvesting applications. EDAX analysis shows that the carbon-to-oxygen ratio of approximately 3.86:1 is typical of well-oxidized graphene oxide, indicating a high oxidation level.