Influence of oxygen impurities on the electronic properties of graphene nanoflakes

Highlights: • Effect of oxygen impurities on the electronic properties of graphene nanoflakes. • This effect depend on concentrations and geometrical pattern of oxygen impurities. • Oxygen impurities is a promising approach for electronic band engineering of GNFs. • Oxygen dopants are the best viable option for enhancement of electronic properties. Controlled chemical doping with oxygen impurities is a promising approach for the electronic band engineering of graphene nanoflakes (GNFs). Based on the first-principles of the density functional theory (DFT) calculations, we investigated the effect of various consternations of substitutional impurities from oxygen atoms on the electronic properties of GNFs. Our results show that the electronic properties of GNFs do not only depend on the oxygen impurity concentrations, but also depend on the geometrical pattern of oxygen impurities in the GNFs. Additionally, we also found interesting electronic properties of GNFs structure, which significantly contribute to that oxygen dopants cause a decreased energy gap. So, our results suggest that substitutional impurities are the best viable option for enhancement of desired electronic properties of GNFs.