Pressure induced phase transition and band gap controlling in defective graphene mono-sheet: Density functional theory

The electronic properties of defective graphene mono-sheet under external pressure were investigated. Density functional theory was implemented to investigate the band gap variations of defective graphene mono-layer under uniaxial systematic and symmetric stress and strain. Besides, the obtained band gap is more controllable compared to other techniques. The band-gap variations with pressure suggests that, upon applying pressure (stress and strain), a tunable band gap of pristine graphene mono layer and graphene with different orientations of Stone-Wales defects can be achieved. We also monitored the influence of applying external pressure on the work function of pristine graphene mono-layer and graphene with Stone-Wales defects. Our results demonstrated that the work function of pristine as well as Stone-Wales defected graphene mono sheet can be efficiently controlled by selecting a specific pressure value.