Two-dimensional graphene superlattice made with partial hydrogenation

Electronic properties of two-dimensional 2D graphene superlattice made with partial hydrogenation were thoroughly studied via density functional tight binding approach which incorporates the tight-binding method into the density functional formalism. The 2D pattern of hydrogen atoms on graphene was found to have great effects on electronic structures of graphene superlattice. In particular, the edges of the 2D pattern, armchair or zigzag, are essential for the energy band gap opening, and the energy band gap sensitively depends on the shape, size, and the 2D periodicity of the pattern. Based on these findings, we suggested that the 2D graphene superlattice could be used in fabricating graphene quantum dots or heterojunctions without the need for cutting or etching. (C) 2010 American Institute of Physics. [doi:10.1063/1.3425664]