Influence of oleylamine–functionalized boron nitride nanosheets on the crystalline phases, mechanical and piezoelectric properties of electrospun PVDF nanofibers

Abstract

Electrospun poly(vinylidene fluoride) nanofibers (PVDFNFs) have been receiving much attention in wearable and self–powered electronics because of their flexibility, biocompatibility and mechanical–to–electrical energy conversion ability. Although various types of nanofillers has been explored to overcome the inadequate mechanical properties and low piezoelectric responses of the PVDFNFs, developing high performance PVDFNFs composites is still challenging one due to limited interfacial interaction between the filler and polymer matrix. This work reports the fabrication of high performance piezoelectric composites comprising PVDFNFs and oleylamine functionalized boron nitride nanosheets (OLABN). The incorporation of OLABN significantly increased the electroactive γ–crystalline phases, Young's modulus (823% enhancement) and ultimate tensile strength (343% enhancement) of PVDFNFs. Furthermore, sharp and rapid piezoelectric outputs can be obtained upon force applied by finger tapping on the composite based piezo sensors. An impressive 133% enhancement in the output power density was achieved for the composites. Moreover, the voltage produced upon finger tapping (~3V) on the PVDFNFs–OLABN (4 wt%) composites sensor can charge a capacitor in 0.2 s and upon further amplification (10×), a 4V light–emitting diode turned onto glow. The findings of this study afford an effective route for the fabrication of high–performance PVDF based composites for energy harvesting applications.