Performance enhancement of triboelectric nanogenerators based on polyvinylidene fluoride/graphene quantum dot composite nanofibers

Abstract

Wearable mechanical energy harvesting technologies have been achieved much attention for the wireless sustainable power source applications. In this study, we have fabricated polyvinylidene fluoride (PVDF)/graphene quantum dot (GQD) composite nanofibers (NFs), which showed improved triboelectric nanogenerator (TENG) performance. PVDF/GQD composite NFs were fabricated by an electrospinning method. Structural and chemical investigations show that the GQDs were embedded in the PVDF NFs and promoted the formation of polar β-phase when an optimal amount of GQDs was incorporated. The PVDF/GQD NFs showed strong photoluminescence at a wavelength of 453 nm, which was attributed to the electronic transitions in the GQDs. As the GQD content increased from 0 to 5 vol%, the maximum output power from TENG devices increased from 35 to 97 μW but decreased with further additions of GQDs. The enhancement and degradation of the TENG performance with increasing the GQD contents were due to the enhanced formation of polar β-phase and the detrimental effect of conductive GQDs for charge trapping, respectively. © 2019 Elsevier B.V.