MoS2 nanoworm thin films for NO2 gas sensing application

MoS2 thin films of different thickness have been deposited using direct current magnetron sputtering. These structures have been utilized as a gas sensor without any additional processing. As the thickness of the MoS2 film increases, surface morphology of the MoS2 films changes from nanoparticle to nanoworm like structures. Nanoworm structure of MoS2 exhibits large surface area and high porosity which provides the quick transfer of charge carriers and active sites for the adsorption and desorption of NO2 gas molecules. A rapid increase in NO2 sensing response is correlated with change in the morphology of MoS2 thin films from nanoparticle to nanoworm like structures. The gas sensing response of nanoworm like MoS2 thin films is measured using the non interdigitated type contacts. The cross-sensitivity of MoS2 nanoworm sensor for NH3, H-2, CO and NO gases is also studied. Our results demonstrate the potential application of such MoS2 nanostructure for fabricating a highly sensitive NO2 gas sensor.