Ti3C2-MXene used to enhance response/recovery speed and thermal stability of acrylate copolymer humidity sensor under abnormal temperature changes

MXene is a typical kind of 2D material with high specific surface, electrial conductivity, self-lubrication and abundant surface groups, which has received wide attention in the fields of electrochemistry, lubrication, sensors and electromagnetic shielding. In this work, MXene-containing polymer matrix composites (MHMA@ Ti3C2) are prepared to enhance the humidity response properties of conventional polyacrylate humidity sensitive materials. The result shows that the humidity response curve of MHMA@ Ti3C2 humidity film shows good linearity (R2 = 0.9992) in the relative humidity range of 30–90 %RH, with a high sensitivity of 63.7 kΩ/%RH. Meanwhile, the humidity response/recovery time of the MHMA@ Ti3C2 humidity film shortened from 310 s/312 s to 30 s/35 s, resulting in a much faster response speed. The wet hysteresis was reduced from 2.1 %RH to 0.34 %RH, and the lowest temperature change coefficient was reduced from 0.60 %RH/℃ to 0.44 %RH/℃ compared with MHMA. In the composites, MXene component significantly enhances the electronic migration capability during the humidity response, which improved the humidity-sensitive properties of the composites, and at the same time enhanced the response speed and temperature change resistance of the composites.