Flexible, wearable triboelectric rubber with tunable surface charge density enabled by regulation of surface functional group density and permittivity

Abstract

Flexible wearable triboelectric nanogenerator (TENG) has attracted immense interest in various application scenarios due to its intrinsic self-powered characteristics. Recently, rubbers with high elasticity are frequently reported to be favored substrates for wearable smart devices to enhance body comfort and contact effects. However, most commercial rubbers are nonpolar and lack of enough polar functional groups even after physical and chemical modification to earn satisfactory surface charge density for high triboelectric performance. Moreover, the combination of high triboelectric and mechanical properties is still a significant challenge for flexible TENG material. In this work, a flexible triboelectric rubber with tunable surface charge density and excellent mechanical properties is demonstrated via a natural polymer assisted dispersion of perovskite nanofiller strategy. The designed rubber-based TENG shows an excellent 310 V triboelectric output, 106 nC transferred charge and 6.14 W·m−2 power density, as well as a favorable mechanical property of 10.69 MPa Young’s modulus and 211 % strain. The material can harvest mechanical energy and charge 1 μF commercial capacitors to 1.8 V in 60 s from nature. When serves as flexible device, it can also self-powered to real-time monition various human behavior and distinguish different speed of vehicle driving conditions. We expect our works will provide a feasible strategy to significantly improve the comprehensive performance of flexible wearable rubber-based TENG and advance the potential application of rubber.