2H-MoS2/Ti3C2Tx MXene composites for enhanced NO2 gas sensing properties at room temperature

Nitrogen dioxide (NO2) is a toxic gas species that poses a great threat to the environment and human health. There are still significant challenges in detecting NO2 gas at room temperature. In this work, 2H-MoS2 nanosheets with controlled morphology were grown on the surface of the few-layer Ti3C2Tx MXene by hydrothermal synthesis and formed unique micro architecture, which aims to complete room temperature detection of NO2. The gas sensors based on the 2H-MoS2/ Ti3C2Tx MXene composites have achieved a high response (65.6%) to 100 ppm NO2 gas at room temperature, which is significantly improved compared with the pure MoS2. The excellent NO2 response and selective properties of 2H-MoS2/Ti3C2Tx MXene composites are attributed to the fast channels for carrier transporting and abundant active sites between 2H-MoS2 and few-layer Ti3C2Tx MXene. The improved sensing performance of the two-dimensional (2D) nanocomposite also provides novel avenues for the modification of other 2D materials and the future development of room temperature gas sensors.