Density-Functional Study of Electronic Band Structure of Graphene with H2, H, and N Impurities

Abstract

Graphene is widely investigated for many applications because of its unique properties. One of the most surprising phenomena is the change of its electronic band structure due to impurities adsorption. The density-functional study has been performed to obtain the electronic band structure of graphene with molecular hydrogen H2, atomic hydrogen H, and atomic nitrogen N impurities. Pure graphene has no band gap because the bonding and anti-bonding states are degenerate at the K point at which the Fermi level passes. Molecular hydrogen H2 adsorption gives the same result, while atomic hydrogen H and nitrogen N adsorptions on graphene could result in indirect-band gaps of 2.67 and 4.68 eV, respectively. These results bring impure graphene as a promising candidate for electronic device applications in the future.