2D-MoS2 and WS2-Based Chemical Gas Sensor

Two-dimensional (2D) nanomaterials have been explored in gas sensing applications because of their excellent physical and chemical properties. In recent years, 2D-transition metal dichalcogenide (TMDs) and their hybrids have shown a propitious potential in the gas sensing application due to their excellent properties like high surface area, abundant adsorption site, and tunable electrical properties. The 2D morphology and layer-by-layer formation of TMDs at the nanoscale have shown the ability to detect gas molecules at lower temperatures or even at room temperature. This chapter will briefly discuss the gas sensing performance of 2D-MoS2 and WS2 nanomaterial and their hybrids towards different gas molecules in the parts-per-million range. We also discussed thoroughly the different strategies to enhance the gas sensing performance of 2D-TMDs. The decoration of zero-dimensional (0D) nanomaterial such as metal nanoparticles (Au, Ag, Pt, Pd), metal oxide nanoparticles (SnO2, ZnO), and other metal chalcogenide quantum dots (Pbs). Heterostructure formation with different nanomaterials including metal oxide, metal dichalcogenide, Mxenes, and a carbon-based material such as reduced graphene oxide enhances the gas sensing performance due to the synergistic effect. Also, the impact of light illumination on the gas-sensing performance was discussed.