Critical Appraisal of the Synergism between Electrospinning and Polymer-Nanofiller Interactions on β-Phase Induction and Piezoelectric Response of PVDF

Piezoelectric polymers have emerged as promising materials for diverse applications, including sensors, nanogenerators, and wearable electronics, owing to their ease of processing, cost-effectiveness, flexibility, and reliable power generation and sensing capabilities. Among these, poly(vinylidene fluoride) (PVDF) stands out due to its exceptionally high piezoelectric coefficient. Enhancing the electroactive β-phase in PVDF is therefore a critical research focus, through conventional approaches such as electrical poling, mechanical stretching, and annealing widely employed. More recently, electrospinning has gained recognition as a highly efficient and economical technique for fabricating PVDF nanofibers with high β-phase content. This review highlights the fundamental principles of electrospinning and examines the key parameters influencing fiber diameter, morphology, and β-phase formation. The role of additives, including ionic liquids, salts, and surfactants, in tailoring the structural and functional properties of electrospun PVDF fibers is discussed in detail. Furthermore, the incorporation of solid-phase nanofillers with varied morphologies, surface characteristics, and intrinsic properties (such as electrical conductivity and piezoelectricity) is explored as a strategy to enhance β-phase content and piezoelectric performance. Finally, select applications of electrospun PVDF nanofibers in energy harvesting, physiological signal monitoring, and the development of pressure, touch, and tactile sensors are presented, underscoring their potential in next-generation smart devices.