Recent Advances in Self-Healing Ionic Flexible Sensors

Ionic flexible sensors (IFSs) convert mechanical deformation into electrical signals through ionic conduction, offering broad adaptability for applications in wearable electronics, soft robotics, and human-machine interfaces. The incorporation of self-healing functionality is essential for IFSs, as it provides a direct solution to the mechanical fragility often encountered in soft and flexible devices during practical use. Self-healing IFSs (SH-IFSs) hold great promise for long-term applications. However, critical challenges persist, such as in achieving a harmonious balance between rapid, efficient self-healing and robust mechanical properties. This review systematically surveys the latest progress in SH-IFSs and elucidates their fundamental working mechanisms and rational material design strategies. We highlight pioneering approaches to circumvent the inherent trade-off between self-healing capability and mechanical robustness, including introducing hybrid dynamic bonds, hierarchical cross-linking networks, separated microphases, and functional fillers. Furthermore, we critically examine the enhanced environmental adaptability of these sensors across different challenging conditions, including cryogenic, high-temperature, dry, and aquatic environments, underscoring their potential for widespread applications. Finally, we emphasize that future advancements require transcending the intrinsic trade-off, pushing performance envelopes, developing predictive designs, enhancing environmental robustness, and achieving device-level integration with scalable manufacturing.