Trilayer MXene Fabric for Integrated Ultrasensitive Pressure Sensor and Wearable Heater

Abstract The rise of Internet of Things and wearable healthcare electronics has prompted the rapid development of wearable pressure sensors. A novel developing trend focuses on a pressure sensor with high sensitivity over a wide pressure range, multifunction, breathability, and excellent wearing comfort, which remains a challenge. To address these issues, an all‐fabric device is designed by loading Ti 3 C 2 T x MXene nanosheets onto woven fabrics through a simple dip‐coating method and sewing three fabric layers with different coating concentrations. The large resistance difference between the high‐resistance middle layer and the low‐resistance outer layer dominates the pressure sensing performance, whereas the two outer layers act as an extraction electrode and flexible Joule heater. The change in internal contact resistance of the trilayer fabric under pressure produces an ultrasensitive (2882–36328 kPa −1 ) pressure sensor over a wide pressure range (0–140 kPa), whereas sensitivity and detection limit can be regulated by controlling the coating concentration of the middle layer. In addition, the all‐fabric structure endows the sensor with excellent wearing comfort. Multilevel and multiscale applications such as pulse contour, high load motion, tactile interface array, and large‐area wearable heater demonstrate the broad application prospects in wearable healthcare electronics of the trilayer fabric.