Enhanced Room-Temperature NO Sensing through Deep Functional Group Hybridization in Nitrogen-Doped Monolayer TiCT.

Nitrogen dioxide (NO) is a significant environmental and human health hazard. Current NO sensors often lack sensitivity and selectivity under ambient conditions. This study investigates ammonia pyrolysis modification of monolayer TiCT MXene to enhance NO detection at room temperature. Nitrogen-doped TiCT demonstrates a substantial improvement in sensitivity, with a response of 8.87% to 50 ppm of NO compared to 0.65% for the original sensor, representing a 13.8-fold increase. The nitrogen-doped sensor also exhibits superior selectivity and linearity for NO under ambient conditions. Theoretical analysis shows that nitrogen incorporation promotes enhanced interaction between TiCT and its surface oxygen-containing functional groups through electronic hybridization, resulting in improved adsorption energy (1.80 |eV|) and electron transfer efficiency (0.67 |e|) for NO, thereby enhancing its gas-sensing performance. This study highlights the potential of ammonia pyrolysis-treated TiCT MXene for advancing NO sensor technologies with heightened performance at room temperature.