Leverage Surface Chemistry for High-Performance Triboelectric Nanogenerators

Abstract

Triboelectric Nanogenerators (TENGs) are a highly efficient approach for mechanical-to-electrical energy conversion based on the coupling effects of contact electrification and electrostatic induction. TENGs have been intensively applied as both sustainable power sources and self-powered active sensors with a collection of compelling features, including lightweight, low cost, flexible structures, extensive material selections, and high performances at low operating frequencies. The output performance of TENGs is largely determined by the surface triboelectric charges density. Thus, manipulating the surface chemical properties via appropriate modification methods is one of the most fundamental strategies to improve the output performances of TENGs. This article systematically reviews the recently reported chemical modification methods for building up high-performance TENGs from four aspects: functional groups modification, ion implantation and decoration, dielectric property engineering, and functional sublayers insertion. This review will highlight the contribution of surface chemistry to the field of triboelectric nanogenerators by assessing the problems that are in desperate need of solving and discussing the field's future directions.

Textile Triboelectric Nanogenerators for Wearable Pulse Wave Monitoring

“…For physical modification [88], surface micro/nano structures, such as wrinkles, pyramid arrays, hemisphere arrays, nanowires, and many others, can enhance the surface charge and facilitate intimate contact with the opposite materials. For chemical modification [89], doping/injecting/ coating the triboelectric materials with extrinsic chemicals can tune and optimize the surface charge affinity, eventually achieving improved output voltages [90]. For biological modification, various biomaterials such as spider silk proteins [91] can be applied, creating an extreme tribopositive layer for enhanced sensing signals.…”

Wearable Biosensors for Non-Invasive Sweat Diagnostics

“…Figure 3a shows a wearable molecular level health monitoring tool developed by researchers at Caltech which is self-powered by human motion [107]. The developed device was powered by a flexible triboelectric nanogenerator (TENG) [108][109][110][111][112][113][114]. It measures Na + and pH of sweat using a potentiometric sensing technique, performs signal processing, and transmits this data to a mobile user interface using Bluetooth to track real-time personal health state.…”

Advances in Triboelectric Nanogenerators for Self‐Powered Regenerative Medicine

“…[29,60,61] In addition, progress in nanostructure patterns for designing triboelectric layers can be exerted for the production of high output in harsh and restricted body environments. [62][63][64][65] Accordingly, over the past 5 years, TENGs have served as stimulators, sensors, self-powered systems in biomedical devices, and even as a prostheses substitute for regeneration and modulation applications. [6,[66][67][68][69][70][71][72][73][74] For instance, TENGs have been used on peripheral nerves to modulate gastric, sciatic, and bladder function, [75,76] cell modulation, [77] and direct muscle stimulation.…”