Computational study of the NO, SO2, and NH3 adsorptions on fragments of 3N-graphene and Al/3N graphene.

The adsorption properties of common gas molecules (NO, NH3, and SO2) on the surface of 3N-graphene and Al/3N graphene fragments are investigated using density functional theory. The adsorption energies have been calculated for the most stable configurations of the molecules on the surface of 3N-graphene and Al/3N graphene fragments. The adsorption energies of Al/3N graphene-gas systems are -220.5 kJ mol-1 for Al/3NG-NO, -111.9 kJ mol-1 for Al/3NG-NH3, and -347.7 kJ mol-1 for Al/3NG-SO2, respectively. Compared with the 3N-graphene fragment, the Al/3N graphene fragment has significant adsorption energy. Furthermore, the molecular orbital, density of states, and electron densities distribution were used to explore the interaction between these molecules and the surface. We found that orbital hybridization exists between these molecules and the Al/3N graphene surface, which indicates that doping Al significantly increases the interaction between the gas molecules and Al/3N graphene. In addition, compared with Li, Al can more powerfully enhance adsorption of the 3N-graphene fragment. The results indicate that Al/3N graphene can be viewed as a new nanomaterial adsorbent for NO, NH3, and SO2.