Résumé
Poly(vinylidene fluoride) (PVDF) nanofibrous films, produced through electrospinning, offer high fraction of electroactive phases, high surface-to-volume ratio, porosity, low weight, and increased length, making them promising candidates for portable and self-powered device technology. Apart from electrospinning, the addition of nanofillers is known to enhance the electroactive responses of PVDF. This work investigates the influence of magnetostrictive and ferromagnetic CoFe2O4 (CFO) and highly piezoelectric KNaNbO3 (KNN) ceramics, dispersed in a lead-free PVDF matrix, serving as magnetic and electric counterparts, respectively. The incorporation of CFO and KNN nanoparticles enhanced the β-phase content of PVDF nanofibers and improved its dielectric and mechanical strength. The energy harvesting performance of the different PVDF-nanocomposites was studied in detail by fabricating single layered piezoelectric nanogenerators (PENGs), stacked multi-layered (SML) PENGs, and hybrid piezo-tribo nanogenerators. The hybrid device based on PVDF/CFO exhibited a peak output voltage of 120 V, a short-circuit current of 21 μA under 9N applied force, and a power density of 28.5 μW/cm2 at 107 Ω load resistance. Hence, the present system could act as an active component in self-sustainable and portable mechanical energy harvesting devices and sensors.