High‐Performance Triboelectric Nanogenerators Based on Electrospun Polyvinylidene Fluoride–Silver Nanowire Composite Nanofibers

Abstract

The preparation of ferroelectric polymer–metallic nanowire composite nanofiber triboelectric layers is described for use in high‐performance triboelectric nanogenerators (TENGs). The electrospun polyvinylidene fluoride (PVDF)–silver nanowire (AgNW) composite and nylon nanofibers are utilized in the TENGs as the top and bottom triboelectric layers, respectively. The electrospinning process facilitates uniaxial stretching of the polymer chains, which enhances the formation of the highly oriented crystalline β‐phase that forms the most polar crystalline phase of PVDF. The addition of AgNWs further promotes the β‐phase crystal formation by introducing electrostatic interactions between the surface charges of the nanowires and the dipoles of the PVDF chains. The extent of β‐phase formation and the resulting variations in the surface charge potential upon the addition of nanowires are systematically analyzed using X‐ray diffraction (XRD) and Kelvin probe force microscopy techniques. The ability of trapping the induced tribocharges increases upon the addition of nanowires to the PVDF matrix. The enhanced surface charge potential and the charge trapping capabilities of the PVDF–AgNW composite nanofibers significantly enhance the TENG output performances. Finally, the mechanical stability of the electrospun nanofibers is dramatically enhanced while maintaining the TENG performances by applying thermal welding near the melting temperature of PVDF.

Humidity Sustained Wearable Pouch‐Type Triboelectric Nanogenerator for Harvesting Mechanical Energy from Human Activities

“…On the other hand, the output performance of TENG devices is also enhanced by modifying the relative permittivity of the dielectric/triboelectric materials . For example, the embedded materials into polymer matrices such as silver nanowires, carbon nanotubes, some dielectric materials, etc. are expected to boost surface electrification and relative permittivity of dielectric (i.e., frictional) materials, which leads to the enhanced output performance of TENGs.…”

Light-induced reversible phase transition in polyvinylidene fluoride-based nanocomposites

“…Polar nanomaterials such as nanoclays, nanocarbons, and inorganic salts have been used as fillers in the PVDF matrix [19,20]. These composites exhibit enhanced ferroelectric, dielectric, and mechanical properties which have been demonstrated for many applications [21,22]. In this context, carbon nanotubes (CNTs) efficiently induce ferroelectric β phase in PVDF due to the electrostatic interaction of -H δ+ -C δ+ -F δ− -dipoles of PVDF with π orbitals of CNTs, as reported in the literature [23,24].…”

Material aspects of triboelectric energy generation and sensors

“…In PVDF nanofibers, the addition of Ag nanowires (Ag NWs) promoted the formation of a β-crystalline phase in the PVDF chains and trapped the electrostatically induced charges at the metal-dielectric interfaces. The synergistic effect increased the output performance of TENGs 71 (Fig. 3d).…”