Ab Initio DFT Study of Band Gap of Armchair and Zigzag Graphenes

Abstract

Graphene sheet is a single-atom thick material and attracts great interest due to its extraordinary physical properties, but it has zero bandgap. At the boundary of graphene sheet, two types of stable edges were the zigzag edge and armchair edge. The electronic states of graphene largely depend on the edge structures. In this research, we used Quantum ESPRESSO package to calculate the band gap of armchair and zigzag graphene due to the increase of their number of cells. The results show that the graphene band gaps are influenced by the number of cells in the armchair and zigzag configuration.