Enhanced piezoelectric performance of PVDF-based electrospun nanofibers by utilizing in situ synthesized graphene-ZnO nanocomposites

In this study, the graphene-zinc oxide nanocomposite was synthesized by hydrothermal method and used in the preparation of electrospun poly(vinylidene fluoride) (PVDF) nanofibers. For this purpose, PVDF nanofibers containing graphene-ZnO nanocomposite (G-ZnO) were prepared and its microstructure and morphology were studied using infrared spectroscopy (FTIR), X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM) techniques. The results showed the production of uniform and bead-free nanofibers. The decrease in PVDF nanofiber diameter (about 23%) was observed with addition of synthesized G-ZnO nanocomposite. It was also observed that the incorporation of G-ZnO nanocomposites increased the crystalline and polar beta phase of the PVDF nanofibers and consequently its piezoelectric properties. The PVDF/G-ZnO nanofibrous composite exhibits a peak-to-peak voltage of 840 mV under an applied force of 1 N, which found to be superior than the pristine PVDF (640 mV) and PVDF/ZnO (710 mV) nanofibers. The results of this work provide new insight for the development of flexible piezoelectric nanofibrous devices and energy harvesting systems.