Wearable pressure sensor based on MXene/single-wall carbon nanotube film with crumpled structure for broad-range measurements

High-performance flexible pressure sensors are attracting great interest owing to their potential applications for electronic skins, human-machine interfaces, and biomedical diagnostics. However, there remain significant challenges for the fabrication of low-cost and high-sensitivity sensors. Here, we report the preparation of Ti3C2Tx MXene/single-wall carbon nanotube (SWNT) composite films through vacuum-assisted filtration followed by thermal shrinkage. SWNTs can effectively prevent MXenes from stacking and improve the electrical performance of the films. The films are used as a flexible piezoresistive sensor for pressures ranging from 33 Pa to 130 kPa. And experimental test results indicate that the fabricated pressure sensors have high sensitivity (116.15 kPa−1 below 40 kPa and 12.7 kPa−1 at 40-130 kPa), a fast response time of 13 ms, and long-term stability over 6000 periods. The sensor can be used to monitor human physiological signals, such as finger movements, voice detection, and wrist pulse in real-time. Moreover, a 4 × 4 sensor array was successfully applied in the pressure distribution mapping of different objects, indicating that the pressure sensor can be applied in electronic skin, medical devices, and other wearable devices.