Ionic Surfactant-Assisted PVDF Nanofabrics with High Dielectric and Excellent Piezoelectric Performance

Abstract

Flexible dielectrics and piezoelectric sensors have attracted a number of applications in advanced electronic systems. In this regard, poly(vinylidene fluoride) (PVDF) is considered as a promising option due to its flexibility and ferroelectric properties. In this study, a highly flexible non-woven fabric was developed from electrospun PVDF nanofibers containing cationic and anionic surfactants. Cetrimonium bromide (CTAB) was used as a cationic surfactant, while sodium lauryl sulfate (SLS) was used as an anionic surfactant. The presence of cationic and anionic surfactants played a pivotal role in the production of finer fibers. PVDF-SLS nano-fabric exhibited oriented fibers, while PVDF-CTAB nano-fabric displayed randomly arranged fibers. PVDF-SLS-based nano-fabric displayed the highest β-phase content of 98.2%, while PVDF-CTAB non-woven showed a β-phase content of 91.6%. A significant improvement in the dielectric properties of PVDF nano-fabric was observed upon the addition of cationic and anionic surfactants. Furthermore, PVDF-SLS nano-fabric demonstrated exceptional dielectric and piezoelectric properties, generating a piezoelectric voltage of ~ 19 V. In comparison, PVDF-CTAB nano-fabric exhibited a piezoelectric voltage of 12.5 V. The power density of PVDF improved significantly upon the addition of SLS surfactant. Such attributes position PVDF-SLS nanofabrics as valuable candidates for diverse applications, particularly in the field of piezoelectric sensors and energy storage devices. The research not only advances the understanding of optimizing PVDF nanofabrics, but also establishes a foundation for future exploration in the realm of flexible electronics. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to the Korean Fiber Society 2024.