Enhancement of piezoelectric responses of electrospun PVDF nanofibers through mechanical stretching and annealing process

•Significant improvements in the piezoelectric properties of PVDF nanofibers.•Mechanical stretching utilized to enhance the piezoelectric performance of the nanofibers.•Annealing process is employed to further optimize the piezoelectric response, achieving superior performance.•Novel and effective methodology for enhancing the piezoelectricity of PVDF nanofibers. Advanced materials play a crucial role in the development and future applications in energy harvesting, sensors, actuators, and flexible electronics across various industries and applications. The objective of this study is to fabricate advanced materials through post-processing treatments (PPTs) of polyvinylidene fluoride (PVDF) electrospun nanofibers. In this study, PVDF nanofibers were fabricated by a facile electrospinning process. Subsequently, the prepared nanofibers were subjected to PPTs such as annealing and mechanical stretching at varying strain rates. The effect of these PPTs is evaluated through thermal response curves. The effect of PPTs reorients the molecular chain arrangements of the electrospun PVDF nanofibers, which is reflected in the piezoelectric coefficient of the processed electrospun nanofibers. Notably, the annealed and stretched nanofibers generate microstrain-based voltage up to 0.428 V, owing to the higher d33 piezoelectric coefficient observed in the TF3 sample (20 wt% PVDF, annealing at 100 °C, 1 mm/mm mechanical strain rate). Overall, the present study demonstrates the improvement of polymorphic phases and molecular reorientation on PVDF electrospun fibers achieved through post-processing treatments, potentially representing a promising novel material for piezoelectric applications.