A Novel High-Performance MXene-Doped Graphene Pressure Sensor

Most of the previous graphene pressure sensors generally have problems, such as poor measurement range, insufficient sensing points, and complex fabrication processes. In order to enhance the performance of graphene pressure sensors with low cost and easy preparation, a novel MXene-doped graphene pressure sensor is designed with double-layer structure in this work. The doped MXene undergoes charge transfer with graphene, inducing scattering of graphene carriers. This process leads to a decrease in the concentration and mobility of graphene carriers, consequently increasing the resistivity of graphene, which in turn increases its sensitivity. The MXene-doped graphene pressure sensor is fabricated with a simple and inexpensive laser-engraved graphene-MXene film technology. The morphological features and microstructure of MXene-doped graphene are characterized with SEM, XRD, and Raman spectrum tests. This MXene-doped graphene pressure sensor can detect the pressure in the range of 0–10 kPa. Compared with previous graphene pressure sensors, the results indicate a significant improvement in sensitivity (2.13 kPa−1, 0–2.48 kPa; 0.23 kPa−1, 2.48–10 kPa). Simultaneously, the sensor exhibits good hysteresis (1.51%) and excellent repeatability (1.69%). The response and recovery times are both less than 13 ms. The influence of the bending radius of a PET substrate on sensor performance has been studied. The smaller the bending radius of the PET substrate, the higher the sensor resistance. Additionally, this sensor has good long-term stability, which enhances its reliability across industrial automation, healthcare, and smart wearables.