UV-Assisted Spinning of Tough, Stretchable and Resilient Ionotronic Fibers for Stable Signal Transmission

The development of tough and stretchable ionic conductors, particularly hydrogels in fiber shape, has facilitated the operation of ionotronic devices under various deformation scenarios by leveraging a hybrid circuit of mobile ions and electrons. However, the production of ionic conductive hydrogel fibers still encounters significant challenges, including the development of efficient fabrication techniques and ensuring long-term durability and reliability, especially in harsh environmental conditions. Herein, we present a continuous and cost-effective UV-assisted spinning method that utilizes deep eutectic solvents (DESs) as substitutes for water in the fabrication of ionic conductive gel fibers, which exhibit remarkable mechanical resilience, conductivity, and exceptional stability under varying temperatures and humidities. The resulting gel fibers display a high ionic conductivity of 0.896 S/m and Young's modulus of 8.7 MPa, rivaling the performances of most hydrogels. Notably, these fibers exhibit exceptional durability, retaining their mechanical and electrical integrity over 365 days of ambient storage without discernible degradation. Moreover, we demonstrate the utility of these fibers in the creation of ionic cables that can reliably transmit high-quality signals even under strain, highlighting their potential for long-term ionotronic applications, including wearable devices and health monitoring systems.