Empowering mechanical energy harvesting and intelligent noise detection with 2D fluorine functionalized BN-PVDF nanofibers based high performance piezoelectric nanogenerator

Abstract

Polyvinylidene fluoride (PVDF) based high performance piezoelectric nanogenerator (PENG) with open-circuit voltage and remarkable short-circuit current density of 55 V and 16 mA/m2 respectively was achieved through an advanced materials design. The PENG was fabricated via incorporating fluorine functionalised boron nitride nanosheets (FBNNs) −formed from single step hydrothermal route- into PVDF matrix through electrospinning. The novel nucleating agent FBNNs effectively aligned the molecular dipoles within PVDF, resulting in a significant increase in the β-phase fraction to 90 % and enhancing crystallinity to 47 %. In comparison to bare electrospun PVDF, the incorporation of 0.5 wt% FBNNs led to a substantial boost (∼ 2000 times) in power density, reaching 0.2 W/m2, showcasing its potential for smart electronics applications. The system was also demonstrated as a self-powered acoustic sensor utilizing the new composite and innovative device design, leveraging its heightened sensitivity to subtle vibrations. The ability of our developed sensor to accurately detect loud sounds exceeding 80 dB positions it as an ideal choice for self-powered noise detection systems. Moreover, this smart sensor could reproduce received audio waves by generating corresponding electrical signals.