Sensing propensity of a defected graphane sheet towards CO, H 2 O and NO 2

We have used density functional theory to investigate the sensing property of a hydrogenated graphene sheet (graphane) towards CO, H 2 O and NO 2 gas molecules. Though the pristine graphane sheet is found not to have sufficient affinity towards the mentioned gas molecules, the defected sheet (removing few surface H atoms) has a strong affinity towards the gas molecules. While CO and H 2 O are found to be weakly physisorbed, the NO 2 molecules are found to be strongly chemi-sorbed to the defected graphane sheet. With NO 2 , the N(p) and O(p) states are found to have strong hybridization with the most active C(p) states which lie at the defected site of the graphane sheet. While increasing the coverage effect of the mentioned gas molecules toward the defected sheet, the adsorption energies do not change significantly. At the same time, the work function of the defected graphane sheet shows an increasing trend while adsorbed with CO, H<...

Tanveer Hussain, Puspamitra Panigrahi and Rajeev Ahuja

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