Materials, Devices, and Systems of On‐Skin Electrodes for Electrophysiological Monitoring and Human–Machine Interfaces

Abstract

On‐skin electrodes function as an ideal platform for collecting high‐quality electrophysiological (EP) signals due to their unique characteristics, such as stretchability, conformal interfaces with skin, biocompatibility, and wearable comfort. The past decade has witnessed great advancements in performance optimization and function extension of on‐skin electrodes. With continuous development and great promise for practical applications, on‐skin electrodes are playing an increasingly important role in EP monitoring and human–machine interfaces (HMI). In this review, the latest progress in the development of on‐skin electrodes and their integrated system is summarized. Desirable features of on‐skin electrodes are briefly discussed from the perspective of performances. Then, recent advances in the development of electrode materials, followed by the analysis of strategies and methods to enhance adhesion and breathability of on‐skin electrodes are examined. In addition, representative integrated electrode systems and practical applications of on‐skin electrodes in healthcare monitoring and HMI are introduced in detail. It is concluded with the discussion of key challenges and opportunities for on‐skin electrodes and their integrated systems.

Materials, Electrical Performance, Mechanisms, Applications, and Manufacturing Approaches for Flexible Strain Sensors

“…Flexible and wearable electronics have recently attracted wide attention due to their great potential applications in real-time human health monitoring systems (e.g., detection of human motions [1][2][3][4], heart-beat [5,6], blood pressure [7][8][9], and beyond [10][11][12]), humanmachine interfaces [13][14][15] (e.g., flexible sensors work as a medium and dialogue interface for the transmission and exchange of information between humans and machines), and implantable devices [6,[16][17][18]] (e.g., transmit the sense of skin touch information to the brain by using electronic skin, and prosthesis was controlled by the cerebral cortex with 3D microelectrodes, etc.). The synchronized delivery and control of the signal from human body to detector or actuator are convenient, expeditious, effective, and accurate compared with traditional rigid conducting and semiconducting materials based on smart devices [19,20].…”

Applications of Bioinspired Reversible Dry and Wet Adhesives: A Review

“…Furthermore, wet adhesives have been applied to sensors to maintain strong adhesion and sensing performance on sweaty skin or underwater (Wu et al, 2021). Many studies have integrated octopus-inspired suckers into sensors.…”

Wireless Soft Scalp Electronics and Virtual Reality System for Motor Imagery‐Based Brain–Machine Interfaces

“…[ 4 , 7 , 9 ] Recent developments in skin‐interfaced electrodes for biopotential acquisition demonstrate new strategies and solutions for on‐skin bioelectronics. [ 10 ] Examples include the use of screen‐printed highly conductive composites [ 11 ] and nanowire‐based networks fabricated via interfacial hydrogen bonding in solution [ 12 ] with excellent stretchability and interfacial conductive properties. There is a multitude of strategies for noninvasive EEG BMI paradigms.…”