Bandgap modulation of partially chlorinated graphene (CCl) nanosheets via biaxial strain and external electric field: a computational study

Density functional theory calculations with van der Waals (vdW) correction were used to investigate the structural and electronic properties of monolayer and bilayer of partially chlorinated graphene (CCl); the effects of biaxial strain and external electric field (E-field) on the electronic structure of CCl nanosheets were also examined. The CCl monolayer is a semiconductor with an indirect bandgap of 1.51 eV. Interestingly, the weak vdW interactions between two CCl monolayers induce a much smaller bandgap in CCl bilayer than that in the single monolayer. More interestingly, the electronic structure of CCl monolayer and bilayer can be feasibly modulated by applying an external E-field and a biaxial strain, and the modulation can even result in semiconductor–metal transition. These findings present very interesting possibilities for tailoring the electronic properties of CCl nanosheets for future electronic devices.