First principles study of Al-doped graphene as nanostructure adsorbent for NO2 and N2O: DFT calculations

We studied the first principles adsorption phenomena of nitrogen dioxide (NO2) and nitrous oxide (N2O) molecules on the surface of pristine graphene and Al-doped graphene using density functional theory (DFT) calculations. The adsorption energies have been calculated for different possible configurations of the molecules on the surface of pristine and Al-doped graphene. Our calculations reveal that the Al-doped graphene has significant adsorption energy, elevated net charge transferring values and smaller bond distances to gases than that of pristine graphene because of the chemical interaction of the mentioned molecules. Furthermore, the calculated density of states (DOS) show the existing of noteworthy orbital hybridization between NO2 as well as N2O and Al-doped graphene during adsorption process which is proving to strong interaction while there is no evidence for hybridization between the those molecules and the pristine graphene. Our calculated adsorption energies for the most stable states for NO2 and N2O was -62.2 kJ mol(-1) (-48.5 kJ mol(-1) BSSE corrected energy) and -33.9 kJ mol(-1) (-22.7 kJ mol(-1) corrected energy), which are correspond to chemisorption process. These results point to the suitability of Al-doped graphene as a powerful sensor for practical applications. (C) 2015 Elsevier B.V. All rights reserved.