Atomic structure and electronic properties of folded graphene nanoribbons: a first-principles study

摘要

The atomic structure, stacking sequences and electronic structure of foldedgraphene nanoribbons (FGNRs) are investigated by first-principles calculations.It reveals that the common configurations of all FGNRs are racket-likestructures including a nanotube-like edge and two flat nanoribbons.Interestingly, the two flat nanoribbons can form new stacking styles instead ofthe most stable AB-stacking sequences for bilayer nanoribbons. The stability ofthe FGNRs are associated with several factors of initial structures, such asinterlayer distance of two nanoribbons, stacking sequences, edge styles, andwidth of nanoribbons. These folded nanoribbons can only be thermodynamicallystable when the width reaches about 61 {\AA} and 95 {\AA} for the zigzag andarmchair nanoribbons, respectively. In addition, the band gap of the foldedzigzag graphene nanoribbons becomes about 0.17 eV, which provides a new way toopen the band gap.