Flexible bifunctional sensor based on porous copper nanowires@IonGels composite films towards high-resolution stress/deformation detection
Flexible wearable electronics, including mornitors, supercapacitors, sensors and batteries, especially stress or strain sensors, which have attracted extensive discussion and attention, due to their distinctive characteristics such as highly sensitive and ultra-flexible, and their broad application prospects in artificial intelligence (AI), robots sensing interface, also high precision medical instruments. However, narrower deformation rate, higher latency, even counterfeit sensitivity severely limits their sensing performance and popularity in practical applications. Herein, a newly bifunctional sensor based on excellent conductive and biocompatible porous copper nanowires (CuNWs)/IonGels (PCIs) composite films introducing polystyrene (PS) microspheres template is developed. The sensor exhibits unparalleled mechanical properties (the maximum extension rate is 8000%), as well as omnidirectional, arbitrary angle/dimension extension, distortion and bending. This piezo-resistive sensor also features a convincing ultra-high sensitivity (S, 72.1 kPa-1) and gauge factor (Gf, 28.5) with negligible hysteresis under repeated cycle tests. Furthermore, compared to the same type of sensor, the limitation of detection (LOD) is drastically reduced (merely 0.14 Pa). Undoubtedly, it is promising for high-resolution strain/stress-sensing electronic skin (e-skin) and green super-stretched electrodes.