Electrospun Pvdf/p-PVC Nanofiber Mats with CaCl 2 Doping and Simultaneous Annealing for Piezoelectric Energy Harvesting Applications

A flexible piezoelectric nanofiber material for energy harvesting was developed from a PVDF/plasticized PVC (p-PVC) blend doped with Calcium Chloride (CaCl2). The non-woven nanofiber mat was fabricated via electrospinning combined with simultaneous annealing during fiber collection, providing a time-efficient strategy in the fabrication process. The novelty of this work lies in the integrated approach of polymer blending, ionic doping, and in-process annealing, enabling measurable improvements in the material’s electroactive properties. p-PVC was incorporated to improve mechanical flexibility and electrolyte uptake, while CaCl2 doping along with annealing enhanced piezoelectric performance. Comprehensive characterization was conducted, including morphology, functional groups, crystallinity, phase formation, thermal stability, mechanical properties, and electrical response. The PVDF/p-PVC/CaCl2 nanofiber mat exhibited an average fiber diameter of 295.2 nm, crystallinity index of 50.3%, and thermal stability with less than 50% mass loss at 400°C. Simultaneous annealing achieving an ultimate tensile strength of 8.2 MPa at 60% elongation at break. Electrically, the mat generated a peak-to-peak voltage of 650 mV, a rapid pressure-induced sensitivity rise time of 36 ms, and a wave period of 256 ms. These results demonstrate its strong potential as a flexible piezoelectric platform for future energy harvesting applications.