title: Thermal dynamics of graphene edges investigated by polarized Raman spectroscopy.
abstract: In this report, we present Raman spectroscopy investigation of the thermal stability and dynamics of graphene edges. It is found that graphene edges (both armchair and zigzag) are not stable and undergo modifications even at temperature as low as 200 °C. On the basis of polarized Raman results, we provide possible structural models on how graphene edges change during annealing. The zigzag edges rearrange and form armchair segments that are ±30° relative to the edge direction, while armchair edges are dominated by armchair segments even at annealing temperature as high as 500 °C. The modifications of edge structures by thermal annealing (zigzag segments rearrange in form of armchair segments) provide a flexible way to control the electronic properties of graphene and graphene nanostructures.
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore.
authors.forename: Ya Nan
authors.initials: YN
authors.lastname: Xu
authors.forename: Da
authors.initials: D
authors.lastname: Zhan
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.forename: Hui
authors.initials: H
authors.lastname: Suo
authors.forename: Zhen Hua
authors.initials: ZH
authors.lastname: Ni
authors.forename: Thuong Thuong
authors.initials: TT
authors.lastname: Nguyen
authors.forename: Chun
authors.initials: C
authors.lastname: Zhao
authors.forename: Ze Xiang
authors.initials: ZX
authors.lastname: Shen