Adsorption and dissociation of NO2 on silicene

Using Density Functional Theory, we have described the full inactivation of NO2 driven by silicene. NO2 is a harmful pollution-generating molecule, causing acid rain. We have studied the minimum energy pathway for the trapping and deactivation of NO2 on silicene substrates. Starting with a configuration in which the molecule and the substrate are not interacting, the NO2 is chemisorbed on silicene, passing through several intermediate states. As the reaction proceeds, the system gains energy, favoring the breaking of the NO2 molecule. In the final state, the molecule is entirely disassociated into N and O atoms, that are incorporated into silicene, forming bonds in bridge positions. The reaction is exothermic, gaining 6.8 eV. These results indicate that silicene is a good substrate to trap NO2 and to completely inactivate it by decomposing it into N and O atoms.