Extremely stretchable and self-healing conductor based on thermoplastic elastomer for all-three-dimensional printed triboelectric nanogenerator

Abstract

Advances in next-generation soft electronic devices rely on the development of highly deformable, healable, and printable energy generators to power these electronics. Development of deformable or wearable energy generators that can simultaneously attain extreme stretchability with superior healability remains a daunting challenge. We address this issue by developing a highly conductive, extremely stretchable, and healable composite based on thermoplastic elastomer with liquid metal and silver flakes as the stretchable conductor for triboelectric nanogenerators. The elastomer is used both as the matrix for the conductor and as the triboelectric layer. The nanogenerator showed a stretchability of 2500% and it recovered its energy-harvesting performance after extreme mechanical damage, due to the supramolecular hydrogen bonding of the thermoplastic elastomer. The composite of the thermoplastic elastomer, liquid metal particles, and silver flakes exhibited an initial conductivity of 6250 S cm −1 and recovered 96.0% of its conductivity after healing.

Stretchable, Transparent, and Thermally Stable Triboelectric Nanogenerators Based on Solvent‐Free Ion‐Conducting Elastomer Electrodes

“…The rapid development of flexible/stretchable electronics has been hindered by one challenge that most state‐of‐the‐art power devices can hardly match the flexibility, stretchability or multifunctionality of the electronics 1,2. For example, high stretchability, self‐healing capability, or transparency has been realized in many reported electronic skins integrated with multifunctional smart sensors, but the research on compatible energy devices still falls behind 3–6. Triboelectric nanogenerators (TENGs), which combine triboelectrifcation and electrostatic induction,3,4 have attracted significant attentions as promising next‐generation mechanical energy‐harvesting devices due to a high degree of freedom for material selection, a variety of operating sources, a high power‐to‐weight ratio, and various device structures 7–13.…”

Smart Sensing Systems Using Wearable Optoelectronics

“…d) The extremely stretchable forms of underlying substrate. Reproduced with permission . Copyright 2019, Springer Nature.…”

“…Gao et al fabricated a transparent, nanocellulose fiber that is disposable and biodegradable with a high mechanical resistance up to 1000 bending cycles (bending angle of 180°) . In addition to hybrid films, polyurethane acrylate (PUA) elastomer is another candidate for wearable optoelectronic sensors due to the wide range of elasticity properties provided by the polymerization method, as shown in Figure d . The entire forms of devices using PUA elastomers can endure up to extreme stretchability (2500%) without failure.…”

Design of Electrode Materials for Stretchable Triboelectric Nanogenerators

“…Both stretchability and self-healing capability of the device is also attributed to the supramolecular hydrogen-bonding of PUA. It takes about 24 h for this TENG to recover at room temperature [34].…”