Rapid Self-Healing Hydrogel with Ultralow Electrical Hysteresis for Wearable Sensing

Abstract

Self-healing hydrogels are in high demand for wearable sensing applications due to their remarkable deformability, high ionic and electrical conductivity, selfadhesiveness to human skin, as well as resilience to both mechanical and electrical damage. However, these hydrogels face challenges such as delayed healing times and unavoidable electrical hysteresis, which limit their practical effectiveness. Here, we introduce a selfhealing hydrogel that exhibits exceptionally rapid healing with a recovery time of less than 0.12 s and an ultralow electrical hysteresis of less than 0.64% under cyclic strains of up to 500%. This hydrogel strikes an ideal balance, without notable trade-offs, between properties such as softness, deformability, ionic and electrical conductivity, selfadhesiveness, response and recovery times, durability, overshoot behavior, and resistance to nonaxial deformations such as twisting, bending, and pressing. Owing to this unique combination of features, the hydrogel is highly suitable for long-term, durable use in wearable sensing applications, including monitoring body movements and electrophysiological activities on the skin.

Unlocking the Potential of Wearable Sensors in Healthcare and Beyond

“…While the sensors themselves do not necessarily need to be novel, innovation in sensor design, utility, or implementation needs to be clearly articulated. Some examples of recent innovation in physical sensors include the rapid self-healing hydrogel that maintains ultralow electrical hysteresis, microstructured pressure sensors that show high sensitivity to foot posture, and thermoelectric hydrogel-based electronic skin for sensing temperature, pulse rate, and sweat content . We anticipate that innovation in the device form factor coupled with meaningful applications of physical sensors will contribute to opportunities of physical sensors to advance healthcare, enhance training of athletes, improve physical therapy, and ease rehabilitation.…”