Abstract: Nowadays, there is a growing global demand for high-performance room temperature gas sensing devices. In this context, we aim to explore the advancements in two-dimensional (2D) Ti₃C₂ MXene role for toxic NO₂ gas sensing at room temperature. The distinctive advantages of 2D Ti₃C₂ MXene, including high electrical conductivity, ample surface area, surface termination groups, and layer structure have garnered significant attention towards NO₂ gas adsorption. Further, the compatible regularity of Ti₃C₂ MXene at the interface of various semiconductors directed the development of potential room-temperature NO₂ gas sensing devices. Further, the leveraging gas sensing (selectivity, response, and recovery) characteristics become increasing attention on Ti₃C₂ MXene/semiconductor interfaces than pure Ti₃C₂ MXene. Elaborative control on the depletion layer through the Schottky barrier formation distinguished the room temperature NO₂ gas sensing and led to the evolution of electrophilic NO₂ gas molecule interaction. Remarkably, the great processability of Ti₃C₂ MXene/semiconductor interface is sensitive to the low detection limit (LOD) of NO₂ gas at parts per billion (ppb) conditions. On the other hand, this review demonstrates the room temperature optoelectronic NO₂ gas sensing capabilities of Ti₃C₂-based composites for emphasizing selectivity and recovery. Interestingly, the Ti₃C₂ MXene/semiconductor composite builds immunity against the atmosphere humidity and achieves stable NO₂ gas sensing. Finally, we have provided conclusions and key points to advance the research on room temperature NO₂ gas sensing of Ti₃C₂ integrated semiconductors.

Key words: Semiconductors, 2D Ti₃C₂ MXene, NO₂ gas sensing, Schottky barrier, Room temperature