Advanced Functional Composite Materials toward E‐Skin for Health Monitoring and Artificial Intelligence

Abstract

Electronic skin (E‐skin), especially the wearable sensors efficiently detect various stimuli attracted huge research interest owing to their potential applications in health monitoring and artificial intelligence. On the other hand, functional polymer composites possessing excellent properties such as light weight, good flexibility, and superior electrical performances, are promising candidates as building blocks for flexible electronics. Accordingly, tremendous efforts are devoted to the development of polymer composites with functional properties for E‐skin applications. Here, recent advances on the controlled fabrication of various fillers based functional polymer composites and their diverse applications in E‐skin are reviewed. In addition, contemporary studies on fabrication strategies, working mechanisms, and device performance for E‐skin based on the functional polymer composites are reviewed, including flexible pressure sensors, strain sensors, temperature sensors, energy harvesters, and transistors. Furthermore, the applications of functional composite based flexible electronics in healthcare and artificial intelligence are discussed. Finally, the existing challenges and opportunities for the functional composite materials based E‐skin are summarized.

Recent advances in smart wearable sensors as electronic skin

“…The incorporation of nanomaterials is one of the main strategies for making capacitive sensors more sensitive. 82 Zhao et al fabricated 3D dielectric layer touch sensors based on thermoplastic polyurethane (TPU) nanofibers and silver nanowires. Using nanofibers containing high effective permittivity and deformation under compression resulted in excellent sensitivity, quick response time, and small detection limit.…”

“…45 Hence, engineered stretchable structures using different nanomaterials such as CNTs, graphene nanosheets, silicon nanoribbons, as well as other nanocrystals and nanoparticles, could be desirable options for e-skin platforms. 82,155 The resistivity of these temperature sensors varies with temperature because of alterations in mobility or the charge carrier density. These temperature sensors mostly use thermoelectric and pyroelectric effects in addition to thermos-resistive properties, producing electricity in response to temperature change without needing an external power supply.…”

Conjugated Polymer-Based Nanocomposites for Pressure Sensors

“…In recent years, flexible sensors have made great progress in material selection, structure design, and practical application [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. Currently, the most widely studied sensing materials include traditional silicon-based materials, flexible and stretchable polymers, and conductive carbon and metal nanostructures, including nanoparticles, nanowires, nanosheets, and nanofibers [ 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 ]. These developed sensing materials have paved the way for the improvements of sensor performances and practical applications.…”

Skin‐Inspired Hierarchical Structure Sensor for Ultrafast Active Human–Robot Interaction

“…Skin, the largest exposed organ of the human body, converts tactile stimulation into electrical impulses through mechanoreceptors to realize the perception of the external environment. To simulate the excellent perceptual performance, biomimetic tactile DOI: 10.1002/admt.202202008 skin [1][2][3][4][5][6][7] has been developed to detect and quantify external stimuli, receiving enormous attention in motion detection, [8,9] health detection, [10][11][12] and human-robot [13][14][15] interaction technologies. The biomimetic tactile skins can be divided into capacitive, [16][17][18] piezoresistive, [19][20][21] piezoelectric, [22] and triboelectric types [23,24] by conduction mechanism.…”