Gas sensing of a saturated tin/defective graphene device

The sensitivity and selectivity of defective graphene to gases is enhanced by implanting single metal adatoms into vacancy sites. Knowledge of the behavior of these devices under the incremental adsorption of gas molecules until saturation is essential for determining the sensitivity of the device in realistic situations as well as for evaluating the applicability of the device in molecular capture and storage. We present a DFT study of incremental gas adsorption of CO$_{2}$, NO$_{2}$, SO$_{2}$ and H$_{2}$S gases on tin adatom-double vacancy graphene system, in the presence and absence of O$_{2}$. Within the NEGF formalism, we analyze the sensitivity and selectivity of the saturated device to the gas species, showing distinctive transport features for each of the gas species.