High-Sensitivity Wearable Flexible Pressure Sensor Based on MXene and Polyaniline for Human Motion Detection

High-performance flexible pressure sensors are widely used in the fields of human motion detection, soft robots, and human–computer interaction. However, existing flexible pressure sensors have issues, such as poor wearability, complex preparation processes, and high preparation costs. Sponges are usually considered excellent carriers for flexible pressure sensors, and when conductive composite materials are loaded onto the sponge skeleton, they can effectively detect pressure changes. Hence, we report a highly sensitive melamine sponge pressure sensor based on MXene/PANI, using a flexible interdigital electrode as the electrode. On the one hand, the addition of MXene greatly improves the conductivity of the sponge. On the other hand, by introducing an appropriate amount of nanorod PANI, the surface roughness of the sponge skeleton is enhanced, effectively improving contact resistance. By utilizing the designed printed interdigital electrode, the effective area in contact with the sponge is increased, effectively improving the sensitivity of the sensor. Experiments have shown that the sensor has a fast response/recovery time (55 ms/50 ms), low detection limit (10.2 Pa), good repeatability, and long-term stability (10,000 cycles). In addition, sensors can not only be applied to wearable detection, detecting physiological signals of the human body, but also utilize 4 × 4 sensor arrays to detect the pressure distribution of objects with different shapes, demonstrating their application value in wearable and artificial electronic skin fields.