Laser-induced graphene-Embedded electrospun PVDF-ZnO: A synergistic piezo-tribo nanogenerator for efficient energy harvesting

Abstract

This study presents development and performance evaluation of piezo-triboelectric hybrid nanogenerators (PTENGs) based on electrospun PVDF nanofibers modified with laser-induced graphene (LIG) and ZnO nanorods. By integrating piezoelectric and triboelectric mechanisms, the devices demonstrate significantly enhanced energy harvesting efficiency. The incorporation of LIG is expected to facilitate charge transport because of its conductive nature, while ZnO nanorods promotes β-phase crystallization in PVDF and enhances dipole alignment. X-ray diffraction and FTIR analyses confirms peak β-phase content of 84.7 % for PLZ-1.5 composition, while DSC reveals enhanced thermal stability and crystallinity (up to 86.4 %). SEM imaging shows improved fiber morphology, partial alignment, and reduced diameter distribution contributing to superior polarization efficiency. The direct piezoelectric charge coefficient (d33) reaches 50 pC/N for PLZ-1.5, indicating enhanced electromechanical coupling. The PLZ-1.5 exhibited highest output voltage (∼200 V) and power density (∼52 mW/cm3) that could glow 82 LEDs. Electrical output trends under varying load resistances confirm the critical role of nanofiller optimization in enhancing performance. These findings show importance of controlled nanofiller integration for maximizing efficiency of PTENGs. The optimized hybrid devices show great potential for application in self-powered sensors, wearable electronics, and next-generation portable energy harvesting systems. © 2025 Elsevier Ltd