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Here, bead-less PVDF/ZnO piezoelectric nanofibers with smooth and uniform morphology have been successfully prepared via electrospinning. SEM micrographs confirmed that the average diameter 87 nm belongs to PVDF nanofibers containing 2wt ZnO nanoparticles. Fourier transform infrared spectroscopy FTIR results showed that electrospinning is solely able to induce the polar β-phase crystals in neat PVDF nanofibers by applying high electric field to the polymeric solution and extremely high stretch ratio of the jet. In addition, the β-phase intensity of nanofibers increases with increasing ZnO content. Finally, electrospun nanofibers were examined as piezoelectric sensors. According to experiments, there is a direct relationship between the output voltage of nanofibers and their β-phase intensity. Therefore, PVDF-2wt ZnO nanofibers with the highest β-phase content produced the largest output voltage of 1 mV.