Nanoscale investigation of ferroelectric properties in electrospun barium titanate/polyvinylidene fluoride composite fibers using piezoresponse force microscopy

Ferroelectric nanostructures have broad applications in nanoscale electronic devices, sensors and actuators. In this study, a two-step electrospinning process was used to fabricate barium titanate (BaTiO₃)/polyvinylidene fluoride (PVDF) composite fibers. Microstructure examination showed that BaTiO₃ fibers were well-dispersed within the PVDF fiber matrix and aligned along the fiber axis. X-ray diffraction (XRD) study revealed that crystalline phases corresponding to both PVDF and BaTiO₃ were found. The domain switching and associated ferro-/piezo-electric properties of the BaTiO₃-PVDF fibers were characterized. Polarization-electric field hysteresis loops obtained using piezoresponse force microscopy (PFM) confirmed the polar domain switching behavior of the fibers. Distinct strain-electric field hysteresis loops were also recorded. Hence, the fibers exhibited well-defined piezoelectric and ferroelectric properties. The results show the potential of these nanostructured composite fibers for applications in miniaturized electronic devices and sensors.