Piezoelectric Nanofiber Mats With Enhanced Elastic Recovery for Smart Fabrics

Abstract

Piezoelectric polymer nanofibers are promising for wearable electronics due to their mechanical compliance and electromechanical responsiveness. Poly(vinylidene fluoride)-trifluoroethylene (PVDF-TrFE) is widely used for its ferroelectric β-phase and favorable piezoelectric properties, yet its limited elasticity hinders applications in soft bioelectronics. Electrospun PVDF-TrFE mats can stretch through fiber rearrangement but lack true elastic recovery unless molecular interactions and junctions are modified. Achieving nanofiber networks that are both stretchable and piezoelectrically stable under cyclic strain remains a challenge. Here, we report a strategy combining PVDF-TrFE with a small fraction of poly(ethylene glycol) bis(amine) (PEG-diamine) and thermal annealing to form fused nanofibrous mats with enhanced elasticity and stable piezoelectric output. The blended mats doubled the strain-to-failure (~30%) compared to pure PVDF-TrFE (~14%) and showed Mullins-like elastic recovery up to approximately 9% with reduced hysteresis. Piezoelectric response improved by approximately 25% in peak voltage (~150 mV), with greater signal stability. Structural analyses (Fourier-transform infrared [FTIR], differential scanning calorimetry [DSC], and X-ray diffraction [XRD]) confirmed increased β-phase content and selective cross-linking in amorphous domains without compromising ferroelectric order. This work demonstrates a scalable material-based approach to improve elasticity and durability in electrospun piezoelectric fibers, enabling stretchable and skin-conformable sensors for smart fabrics, wearable health monitors, and energy harvesting.