Low‐Temperature Bending Fatigue of MXene/PDMS Flexible Pressure Sensor

Abstract The flexible and wearable Ti 3 C 2 (MXene)‐based sensors are attracting wide attention in various applications owing to high sensitivity and flexibility. However, as a key characteristic, the bending endurance of such sensors under low temperature is yet to be explored. Herein, the flexible MXene/polydimethylsiloxane (PDMS) pressure sensor is fabricated by dip coating, which exhibits good mechanical stability over 10 000 bending cycles above 10 °C. When the temperature decreases to −40 °C, a terrible deterioration of bending endurance is observed. The finite element analysis results and theoretical calculation suggest that the accelerated rupture of van der Waals (VDW) interactions between MXene nanosheets and that at the MXene/PDMS interface is responsible for such observation. At temperature above 10 °C, owing to the absorption of strain energy by PDMS, the rupture rate of VDW forces is relatively low. However, the decrease of temperature leads to the reduce of the strain energy stored in PDMS and thus accelerates the rupture of VDW interactions, which significantly deteriorates the bending endurance for the sensor.