title: Imaging local electronic corrugations and doped regions in graphene.
abstract: Electronic structure heterogeneities are ubiquitous in two-dimensional graphene and profoundly impact the transport properties of this material. Here we show the mapping of discrete electronic domains within a single graphene sheet using scanning transmission X-ray microscopy in conjunction with ab initio density functional theory calculations. Scanning transmission X-ray microscopy imaging provides a wealth of detail regarding the extent to which the unoccupied levels of graphene are modified by corrugation, doping and adventitious impurities, as a result of synthesis and processing. Local electronic corrugations, visualized as distortions of the π*cloud, have been imaged alongside inhomogeneously doped regions characterized by distinctive spectral signatures of altered unoccupied density of states. The combination of density functional theory calculations, scanning transmission X-ray microscopy imaging, and in situ near-edge X-ray absorption fine structure spectroscopy experiments also provide resolution of a longstanding debate in the literature regarding the spectral assignments of pre-edge and interlayer states.
authors.affiliation: Department of Chemistry, University at Buffalo, State University of New York, USA. sb244@buffalo.edu
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Schultz
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Patridge
authors.forename: Vincent
authors.initials: V
authors.lastname: Lee
authors.forename: Cherno
authors.initials: C
authors.lastname: Jaye
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Lysaght
authors.forename: Casey
authors.initials: C
authors.lastname: Smith
authors.forename: Joel
authors.initials: J
authors.lastname: Barnett
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Fischer
authors.forename: David
authors.initials: D
authors.lastname: Prendergast
authors.forename: Sarbajit
authors.initials: S
authors.lastname: Banerjee
mesh_terms: D004553:Electric Conductivity; D004581:Electronics; D006108:Graphite / Q000737:chemistry*; D017348:Microscopy, Electron, Scanning Transmission; D008956:Models, Chemical; D008968:Molecular Conformation; D056928:X-Ray Absorption Spectroscopy
chemical_list: D006108:Graphite