Stretchable, Adhesive, and Self‐Healable Liquid‐Free Electron‐Conductive Electronics for Wearable Strain Sensors

Abstract Performance degradation and even loss of function due to mechanical stiffening caused by internal water evaporation and/or freezing significantly limit the application of hydrogel‐based electronics. Herein, a high‐performance liquid‐free electronic skin (e‐skin) is assembled based on the dry poly(ethylene glycol)‐based gel and conductive Ti3C2 MXenes that is successfully applied in wearable strain sensors. The fabricated liquid‐free e‐skin exhibits superior mechanical performance, broad sensing ranges (>1000%), good temperature adaptability, and durable environmental stability. Without extra sealed packaging, the e‐skin sensor maintains remarkable cycling stability and retains 98.5% conductivity at room temperature after 6 months. Furthermore, the liquid‐free e‐skin sensors are utilized to provide individuals with proper guidance on body alignment and posture awareness, fostering the development and maintenance of correct exercise techniques, thus mitigating the likelihood of sports‐related injuries. This work provides a novel liquid‐free electron‐conductive electronic integrated with adhesiveness, stretchability, self‐healabilitiy, and antifreezing, which can meet wide application needs from artificial skins to smart interfaces.