ABSTRACT
MXenes, being two-dimensional (2D) metal nitrides and carbides, have gained the vast interest of the research community in the field of gas and vapor sensing owing to their remarkable characteristics, including 2D morphology, excellent conductivity, high effective surface area, significant hydrophilicity, mechanical flexibility, and rich surface functionalities. The properties of MXenes can be optimized during synthesis using various tunable etching methods. However, their sensing performance is limited by certain drawbacks, including easy restacking, poor stability in oxygen, mass production, incomplete and slow recovery, and room temperature operation. On the contrary, various polymers are vastly used for gas and vapor sensing due to their ease of synthesis, scope to play with morphology, room temperature operation, flexibility, low cost, and high sensitivity. The merits of both the type of materials have been incorporated in MXene–polymer nanocomposites (MXPNs) for enhanced sensing characteristics in terms of three essential Ss (selectivity, stability, sensitivity) and five important Rs (range of detection, repeatability, reproducibility, recovery, room temperature operation). MXene–polymer nanocomposites show excellent sensing properties owing to their enhanced interlayer spacing and unique surface chemistries. This chapter describes the state-of-art MXPNs chemiresistors in-depth to detect various analytes, challenges, and prospects.
