Carbon Quantum Dot Functionalized Nanofiber-Based Triboelectric Nanogenerator With Boosted Output and Fluorescence Function

Abstract

Advanced nanofibrous materials with excellent performance and functional integration is highly desired for developing emerging wearable electronics. In this work, carbon quantum dots/poly(vinylidene fluoride) (CDs/PVDF) based composite nanofibrous material is proposed and acts as a highly negative material to boost output performance for triboelectric nanogenerators (TENGs). The nanometer-sized and surface-functionalized CDs acting as nucleating inducers facilitate the polarized β-phase transition of PVDF polymer. The more negative surface charge density of CDs/PVDF nanofibrous membrane is generated through the polarized β-phase PVDF, thereby leading to a larger electrostatic potential difference to enhance charge transfer. Besides the decreased beaded defects, more uniform morphology fibers are yielded to improve the effective contact surface area. Moreover, the CDs/PVDF composite nanofibers demonstrate the unique multicolor fluorescence effect enabling promising applications in visualized displays and sensing. Finally, the fabricated TENG features a short-circuit current density of ~61.8 mA/m² and a maximum peak power density of ~11.7 W/m², exceeding that of most state-of-the-art nanofiber-based TENG reported to date. As a demonstration of application potential, this TENG shows the energy-harvesting ability to charge capacitors and light up 125 green LEDs and self-powered sensing capability for human motion monitoring. This work provides insights for exploiting novel tribomaterials for high-output TENGs with promising potential in biomechanical energy harvesting, self-powered sensing, and so forth.