Multiarray Gas Sensors Using Ternary Combined TiCT MXene-Based Nanocomposites.

This paper reports chemiresistive multiarray gas sensors through the synthesized ternary nanocomposites, using a one-pot method to integrate two-dimensional MXene (TiCT) with Ti-doped WO (Ti-WO/TiCT) and TiCT with Pd-doped SnO (Pd-SnO/TiCT). The gas sensors based on Ti-WO/TiCT and Pd-SnO/TiCT exhibit exceptional sensitivity, particularly in detecting 70% at 1 ppm acetone and 91.1% at 1 ppm of HS. Notably, our sensors demonstrate a remarkable sensing performance in the low-ppb range for acetone and HS. Specifically, the Ti-WO/TiCT sensor demonstrates a detection limit of 0.035 ppb for acetone, and the Pd-SnO/TiCT sensor shows 0.116 ppb for HS. Simultaneous measurements with Ti-WO/TiCT- and Pd-SnO/TiCT-based sensors enable the evaluation of both the concentration and type of unknown target gases, such as acetone or HS. Furthermore, density functional theory calculations are performed to clarify the role of Ti and Pd doping in enhancing the performance of Ti-WO/TiCT and Pd-SnO/TiCT nanocomposites. Theoretical simulations contribute to a deeper understanding of the doping effects, providing essential insights into the mechanisms underlying the enhanced gas response of the gas sensors. Overall, this work provides valuable insights into the gas-sensing mechanisms and introduces a novel approach for high-performance multiarray gas sensing.