Tailoring Piezoelectric Properties of ZnO-PVDF Nanocomposite for Intelligent Infrastructure Monitoring

Piezoelectric materials are of increasing interest for the development of sensor technologies, due to their unique capability of converting mechanical energy into electrical energy and vice versa. In general, conventional piezoelectric materials such as lead zirconate titanate (PZT) have been extensively studied for these properties. However, their inherent brittleness, toxicity giving rise to environmental concerns and high production costs have hindered their application in advanced sensing technologies for civil infrastructure. In view of this, organic piezoelectric polymers have been the new attraction of the field due to their flexibility, chemical stability, and inherent piezoelectric characteristics. Among these polymers, polyvinylidene fluoride (PVDF) has attracted significant attention due to its high mechanical strength, chemical resistance, and ease of processing. These characteristics make PVDF a promising candidate for flexible and durable sensor applications. However, its comparatively lower piezoelectric output has raised concerns for its effectiveness. To address this limitation, our study proposes and investigates the incorporation of zinc oxide (ZnO) nanostructures into PVDF to enhance its piezoelectric performance. By combining electrospinning and hydrothermal growth techniques, we aim to fabricate ZnO-PVDF nanocomposites with improved dipole alignment and interfacial interaction, thereby boosting the overall electromechanical response.

This study systematically examines the influence of electrospinning parameters on PVDF nanofiber formation, identifies the optimal hydrothermal growth conditions for the ZnO crystal formation on PVDF nanofibers to fabricate the ZnO-PVDF nanocomposite, and evaluates how the composites morphology affects its piezoelectric properties. The results demonstrate that the ZnO-PVDF nanocomposite exhibits enhanced β-phase content and improved piezoelectric response (as indicated by higher d₃₃ values) compared to pristine PVDF. Furthermore, this work paves the way for the integration of the proposed flexible piezoelectric sensors into future intelligent structural monitoring systems. Overall, this study contributes to the development of multifunctional materials with promising applications as flexible, sustainable, and self-powered electronic devices.