title: Atomic level spatial variations of energy states along graphene edges.
abstract: The local atomic bonding of carbon atoms around the edge of graphene is examined by aberration-corrected scanning transmission electron microscopy (STEM) combined with electron energy loss spectroscopy (EELS). High-resolution 2D maps of the EELS combined with atomic resolution annular dark field STEM images enables correlations between the carbon K-edge EELS and the atomic structure. We show that energy states of graphene edges vary across individual atoms along the edge according to their specific C-C bonding, as well as perpendicular to the edge. Unique spectroscopic peaks from the EELS are assigned to specific C atoms, which enables unambiguous spectroscopic fingerprint identification for the atomic structure of graphene edges with unprecedented detail.
authors.affiliation: Department of Materials, University of Oxford , Parks Road, Oxford, OX1 3PH, United Kingdom.
authors.forename: Jamie H
authors.initials: JH
authors.lastname: Warner
authors.forename: Yung-Chang
authors.initials: YC
authors.lastname: Lin
authors.forename: Kuang
authors.initials: K
authors.lastname: He
authors.forename: Masanori
authors.initials: M
authors.lastname: Koshino
authors.forename: Kazu
authors.initials: K
authors.lastname: Suenaga
keywords: Carbon; EELS; Edge states; Graphene; STEM; TEM