Effect of H-vacancy defect on the adsorption of CO and NO on graphane: A DFT study

We investigated the adsorption of CO and NO molecules on hydrogenated graphene (graphane) monolayer using density functional theory (DFT) calculations. The geometry, adsorption stability, and electronic properties of CO and NO molecules absorbed on pure and H-vacancy defected graphane sheet were performed. The calculated results suggested that the small adsorption energy indicated the adsorption of CO and NO molecules on pure graphane were physisorption. However, the presence of H-vacancy improved the reactivity of graphane and the adsorption on H-vacnacy defected graphane changed to chemisorption. The adsorption also induced obvious change into the band gaps, which can be seen as signal to detect the CO and NO gas.