X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge

Beilstein Journal of Nanotechnology

Adam P. Hitchock¹  Xiaoxing Ke²  Gustaaf Van Tendeloo²  Carla Bittencourt²  Peter Guttmann³  Chris P. Ewels⁴ 

[1] Chemistry & Chemical Biology, McMaster University, L8S4M1 Hamilton, ON, Canada;Electron Microscopy for Materials Science (EMAT), University of Antwerp, B-2020 Antwerp, Belgium;Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institute for Soft Matter and Functional Materials, D-12489 Berlin, Germany;Institut des Matériaux Jean Rouxel (IMN), Université de Nantes, CNRS, Nantes, France;

关键词: carbon;    graphene;    nanostructure;    NEXAFS;    X-ray microscopy;   

DOI  :  10.3762/bjnano.3.39

来源: DOAJ

【 摘 要 】

We demonstrate that near-edge X-ray-absorption fine-structure spectra combined with full-field transmission X-ray microscopy can be used to study the electronic structure of graphite flakes consisting of a few graphene layers. The flake was produced by exfoliation using sodium cholate and then isolated by means of density-gradient ultracentrifugation. An image sequence around the carbon K-edge, analyzed by using reference spectra for the in-plane and out-of-plane regions of the sample, is used to map and spectrally characterize the flat and folded regions of the flake. Additional spectral features in both π and σ regions are observed, which may be related to the presence of topological defects. Doping by metal impurities that were present in the original exfoliated graphite is indicated by the presence of a pre-edge signal at 284.2 eV.

【 授权许可】

Unknown