Microstructured Mxene/Polyurethane Fibrous Membrane For Highly Sensitive Strain Sensing With Ultra-Wide And Tunable Sensing Range

Stretchable strain sensors have exhibited emerging prospects in bioelectronics due to the ubiquitous health-related strain in biosystems. However, most of the existing stretchable strain sensors are plagued by their sensitivity and sensing range trade-off. In this study, we designed a microstructured MXene/polyurethane fibrous membrane (m-MXene FM) with porous network structures and tunable micropatterns (including microcracks and microwrinkles), and demonstrated its superior strain sensing properties. The microcracks can serve as stable mechanical weak points to enhance the sensitivity, while the highly porous network as well as the microwrinkle patterns can cushion the strain loading on individual fibers under large deformations, thus offering wide sensing range. The as-prepared m-MXene FM is highly stretchable and conductive and shows extremely high gauge factor of 1000 and wide sensing range up to 120%. Furthermore, both the sensitivity and sensing range can be facilely tailored through adjusting the micropatterns. This work provides a scalable strategy to fabricate highly sensitive strain sensors with customizable sensing properties suitable for a range of applications in health monitoring.