A wearable 3D pressure sensor based on electrostatic self-assembly MXene/chitosan sponge and insulating PVP spacer
Zerui Liu, Yulin Zhang, Yuxiang Song, Yong Lu, Ting Liu, Jicai Zhang
Abstract
Abstract It has been shown that flexible pressure sensors may be used in many different contexts, including human-machine interaction, intelligent robots, and health monitoring. In this work, we create a 3D sponge piezoresistive pressure sensor using MXene, chitosan, polyurethane sponge, and polyvinyl pyrrolidone (MXene/CS/PU sponge/PVP), with the well-conductive MXene nanosheet serving as the force sensitive material. In particular, the mechanical strength and endurance of the sensor are enhanced by electrostatic self-assembly between the negatively charged MXene nanosheets and the positively charged CS/PU composite sponge skeleton. The insulating PVP nanowires (PVP-NWs) also decreases the device’s initial current, increasing the sensor’s sensitivity. These characteristics allow the pressure sensor to simultaneously have a high sensitivity (50.27 kPa −1 for pressure below 7 kPa and 13.3 kPa −1 for pressure between 7 and 16 kPa), a quick response time (160 ms), a short recovery time (130 ms), and excellent cycling stability (5000 cycles). Moreover, the sensor exhibits a waterproof performance, where the force-sensitive layer still works normally after cleaning. In practice, the sensor could detect a variety of human actions as well as the distribution of spatial pressure due to the above superior device performance.