Comprehensive dependence of triboelectric nanogenerator on dielectric thickness and external impact for high electric outputs

Abstract

Triboelectric nanogenerators (TENGs) have aroused extensive interests in recent years, and their energy conversion efficiency increased gradually under massive efforts. Applied force and dielectric thickness are two important factors accounting for the high output performance. Nevertheless, for the most commonly used TENGs in the contact-separation mode, the comprehensive dependence of dielectric thickness and impact force is still expected to be further deeply researched and optimized. Hence, we fabricated a nylon-PTFE TENG in the contact-separation mode and explored the dual influence of dielectric thickness and applied force on the output performance. The results indicate that the dielectric thickness and the magnitude of force have a comprehensive influence on the outputs, which is due to the dual effect of charge transport properties and the microcosmic deformation at different thicknesses. In general, the optimum thickness increases from 0.5 mm to 0.7 mm obviously as the force magnitude increases from 15 N to 60 N, but stays steadily with varying fabric count. With the continuous enlargement of impact force, the dielectric thickness reaches a boundary limitation of 0.8 mm. This work contributes greatly not only to the design and optimization of TENG devices, but also to the deeper understanding of the nano-triboelectric effect mechanism.