A Multifunctional Electronic Skin Empowered with Damage Mapping and Autonomic Acceleration of Self‐Healing in Designated Locations

Abstract

Integrating self‐healing capabilities into soft electronic devices and sensors is important for increasing their reliability, longevity, and sustainability. Although some advances in self‐healing soft electronics have been made, many challenges have been hindering their integration in digital electronics and their use in real‐world conditions. Herein, an electronic skin (e‐skin) with high sensing performance toward temperature, pressure, and pH levels—both at ambient and/or in underwater conditions is reported. The e‐skin is empowered with a novel self‐repair capability that consists of an intrinsic mechanism for efficient self‐healing of small‐scale damages as well as an extrinsic mechanism for damage mapping and on‐demand self‐healing of big‐scale damages in designated locations. The overall design is based on a multilayered structure that integrates a neuron‐like nanostructured network for self‐monitoring and damage detection and an array of electrical heaters for selective self‐repair. This system has significantly enhanced self‐healing capabilities; for example, it can decrease the healing time of microscratches from 24 h to 30 s. The electronic platform lays down the foundation for the development of a new subcategory of self‐healing devices in which electronic circuit design is used for self‐monitoring, healing, and restoring proper device function.

Self‐Healing Soft Sensors: From Material Design to Implementation

“…Composites with a very wide range of conductivities have been used (e.g., 10 −8 to 10 3 S cm −1 ). [ 38,39 ] Electrode materials were usually obtained by high loadings of very conductive fillers (e.g., CNTs, [ 27,36 ] silver nanowires (AgNWs), [ 40 ] Ag flakes, [ 33 ] graphene, [ 41 ] and liquid metal). [ 38 ] By contrast, low‐conductive (resistive) materials that play a significant role in many sensing applications, e.g., gas and pressure sensors, were prepared by filling ratios close to the percolation threshold.…”

“…In several interesting examples, multifunctionality included also signal responsiveness and actuations, [ 66,85,107 ] fluorescence and luminescent functionalities, [ 108 ] self‐monitoring and self‐repair capabilities. [ 40 ]…”

“…Haick and co‐workers [ 40 ] have reported a multifunctional e‐skin with high sensing performance toward temperature, pressure, and pH levels, at both ambient and underwater conditions ( Figure a). The e‐skin was empowered with a novel intrinsic self‐repair capability for efficient self‐healing of small‐scale damage as well as an extrinsic mechanism for damage mapping and on‐demand accelerated self‐healing of large‐scale damage in designated locations.…”

“…a–c) Reproduced with permission. [ 40 ] Copyright 2020, Wiley‐VCH. d) Multifunctional self‐healable e‐skin device on skin while running an LEC operation that emits a blue‐green light.…”

“…[ 76,137 ] Several examples of e‐skin with self‐healing capabilities have been demonstrated recently. [ 36,40,76 ] Considering the different targeted stimuli and the high functionality, all these novel self‐healing e‐skins can be categorized as multimodal and multifunctional systems, as discussed in previous sections. In addition to the two e‐skins shown in Section 4.1, we will discuss another interesting design of a robust, rehealable, fully recyclable and malleable e‐skin.…”