Breathable Ti₃C₂T_x MXene/Protein Nanocomposites for Ultrasensitive Medical Pressure Sensor with Degradability in Solvents

Flexible, breathable, and degradable pressure sensors with excellent sensing performance are drawing tremendous attention for various practical applications in wearable artificial skins, healthcare monitoring, and artificial intelligence due to their flexibility, breathability, lightweight, decreased electronic rubbish, and environmentally friendly impact. However, traditional plastic or elastomer substrates with impermeability, uncomfortableness, mechanical mismatches, and nondegradability greatly restricted their practical applications. Therefore, the fabrication of such pressure sensors with high flexibility, facile degradability, and breathability is still a critical challenge and highly desired. Herein, we present a wearable, breathable, degradable, and highly sensitive MXene/protein nanocomposites-based pressure sensor. The fabricated MXene/protein-based pressure sensor is assembled from a breathable conductive MXene coated silk fibroin nanofiber (MXene-SF) membrane and a silk fibroin nanofiber membrane patterned with a MXene ink-printed (MXene ink-SF) interdigitated electrode, which can serve as the sensing layer and the electrode layer, respectively. The assembled pressure sensor exhibits a wide sensing range (up to 39.3 kPa), high sensitivity (298.4 kPa^-1 for 1.4-15.7 kPa; 171.9 kPa^-1 for 15.7-39.3 kPa), fast response/recovery time (7/16 ms), reliable breathability, excellent cycling stability over 10 000 cycles, good biocompatibility, and robust degradability. Furthermore, it shows great sensing performance in monitoring human psychological signals, acting as an artificial skin for the quantitative illustration of pressure distribution, and wireless biomonitoring in real time. Considering the biodegradable and breathable features, the sensor may become promising to find potential applications in smart electronic skins, human motion detection, disease diagnosis, and human-machine interaction.