Facile method to enhance output performance of bacterial cellulose nanofiber based triboelectric nanogenerator by controlling micro-nano structure and dielectric constant

The development of triboelectric nanogenerators (TENGs) can convert mechanical energy into electricity and bring new prospect for energy crisis. Improving tribo-charge surface density and contact area are two pivotal factors to enhance the output performance of TENG. However, improving the charge density and manipulating surface structure cannot be achieved simultaneously and complicated fabrication procedures may limit application of TENG. In this work, an environment friendly TENG based on bacteria cellulose film fabricated via facile vacuum filtration method was reported. In the presence of modifications, high dielectric particles BaTiO3 were introduced into BC nanofiber film to improve the dielectric constant as well as construct micro-nano structure at the same. With the combination of the enhancement of dielectric constant and surface structure of BC nanofibers layer, the open voltage of 181 V, the short current of 21 μA, and transfer charge of 76.6 nC was achieved at a frequency of 2 Hz and a peak force of 42 N with the optimized film consisting of 13.5 vol% BaTiO3 particles. Additionally, a peak power density of 4.8 W/m2 was achieved when connecting with the resistance in series. Moreover, the TENG showed excellent stability and can harvest the mechanical energy by human motion. This work gives a better understanding of the triboelectricity produced by the TENG from the point of materials and provides a feasible and effective way to enhance the output performance of TENG from the material itself as well as surface modification.