Ultra-Flexible, Anti-Freezing, and Adhesive Collagen Fiber-Derived Conductive Organohydrogel E-Skin for Strain, Humidity, Temperature, and Bioelectric Sensing Applications
Rongrong Zhao, Jianxun Luo, Jiachang Liu, Ke Tao, Jinwei Zhang, Carmen Gaidău, Jin Zhou, Haibin Gu
Abstract
The development of biomimetic electronic skin (e-skin) has significant value in many fields, including health monitoring, soft robotics, wearable electronic devices, and human-machine interaction. As a potential candidate for e-skin, the application of conductive hydrogel is limited by many factors, such as a complicated fabrication process, insufficient mechanical performance, poor environmental stability, and difficulty in degradation. Here, we adopted a top-down strategy to construct a multifunctional collagen fiber-derived conductive organohydrogel e-skin, in which the collagen fiber scaffold of goatskin was filled with a polyacrylamide network. This organohydrogel displayed excellent fracture stress (2.87 MPa) and fracture strain (542%). It could maintain its multifunctionality even at −20 °C and after long-term storage. Additionally, this organohydrogel demonstrated considerable adhesion and antibacterial properties, allowing it to conform closely to human skin without causing bacterial infection. The e-skin sensors, assembled with this organohydrogel, possessed multiple stimuli-responsive modes to achieve strain, humidity, temperature, and bioelectric responsiveness, allowing for the precise monitoring of body movements, facial expressions, voice communication, and physiological signals. Notably, the discarded e-skin could be effectively degraded under natural environmental conditions. In brief, this study gives new opinions about the development of intelligent multifunctional e-skin and demonstrates a new pathway for the high-value utilization of animal skin.