Piezoelectric properties of PVDF/MWCNT nanofiber using near-field electrospinning

This study reports the use of near-field electrospinning to fabricate polyvinylidene fluoride (PVDF) piezoelectric nanofibers mixed with multiwalled-carbon nanotubes (MWCNT). This study also investigates the mechanical strength and piezoelectric characteristics of a single PVDF/MWCNT nanofiber. The morphology and polarization intensity of piezoelectric fiber can be controlled by adjusting the traveling velocity of the X–Y stage, the DC voltage, and the gap between the needle and collection plate. The optimal parameters of the PVDF solution, such as the PVDF powder weight percentage and MWCNT content, were also determined. X-ray diffraction (XRD) analysis shows a high diffraction peak at 2θ = 20.8° in the piezoelectric crystal β-phase structure. ANSYS finite element analysis (FEA) software with coupled field analysis was used to realize piezoelectric actuation behavior of the PVDF fibers. A nano-indentation test (NanoIndenter XP System, MTS co.) was used to investigate Young's modulus of the PVDF fiber. Finally, the fixed–fixed beam structures of PVDF composite fibers were tested using a DC voltage supply. Comparing the polarized fiber with non-polarized fibers, the measurement of the center displacements as a function of electric field was conducted and characterized.