A DFT study of structural, electronic and optical properties of heteroatom doped monolayer graphene

In this paper we present a theoretical work on the influence of doped and co-doped Al, Al-S, Al-N and Al-P heteroatoms in the mono layer graphene surface. The Density functional study reveals that, Al, P and S co-doping significantly modifies the neighborhood bonding arrangement of the graphene sheet. The Natural population analysis revels that Al, P and S co-doping makes the graphene surface as electron rich system. From the molecular orbital analysis it is found that HOMO-LUMO energy gap decreases by starting from the pristine graphene in following manner Al doping > Al-S co-doping> Al-N co-doping >Al-P co-doping. On the other hand, the time dependent density functional theory (TD-DFT) calculation shows that the maximum absorbing wavelength of Al-P and Al-N co-doped graphene systems shifted towards the lower wavelength range with respect to Al doped graphene.