Band Gap Tuning of Hydrogenated Graphene: H Coverage and Configuration Dependence

Abstract

The electronic states of partially hydrogenated graphene (HG) structures are studied by the density functional theory calculations. Several types of HG configurations, including randomly removing of H pair, randomly removing individual H atoms, and ordered H pairs removal, are investigated. We find that the configurations with randomly removing H pairs are most energetically favorable. More interestingly, the band gap for such configurations decrease with H concentration and approaches zero around 67% H coverage. The ability to continuously tune the band gap of hydrogenated graphene from 0 to 4.66 eV by different H coverage provides a new pathway for engineering the electronic structure of graphene materials and enhances their applications in electronics and photonics.