Imaging the domains in nitrogen doped graphene

We explored microstructure of N- doped graphene layer grown by CVD on Ni(111) substrate. The N-graphene was synthesized and studied with µ-ARPES at Spectromicroscopy beamline.

D. Usachov et al.Nano Letters, 11, 5401 (2011).
The N-graphene was synthesized at 600 oC and studied with µ-ARPES at Spectromicroscopy beamline. On the figure (a,c) μARPES-derived photoemission spectra, aquired from the areas of A- and B-type domains of Au intercalated N-graphene with photon energy of 27 eV in the ΓK direction of the corresponding domains. (b,d) The real space structure of graphene domains, visualized with PE microscopy at different PE azimuthal angles, corresponding to the highest intensity of the π-band in the mapping point, shown in panel a. Light areas indicate high photoemission intensity. In this image, the bright regions correspond to the intense photoemission signal delivered by the fast π electrons of the A-domains. The dark regions appear due to the local prevalence of B-domains, rotated by ∼300 and, therefore, not contributing to the PE intensity. After changing the analyzer acquisition azimuth by 300, we obtained the image displayed in Figure d. Here the B-domains give main contribution to the PE intensity. A comparison of the highlighted regions in Figure b,d shows that both images are complementary. The band structure measured from B-domains is shown in Figure 6. Its overall intensity is smaller than in the case of A-domains (Figure a) and the top of the π-band is blurred due to certain orientational disorder.
The results are published as a part of the research collaboration of St. Petersburg State University, IFW Dresden, Vienna University, MAX-lab, BESSY II, Institute of Solid State Physics at Dresden and Elettra

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 Nitrogen-doped graphene: efficient growth, structure, and electronic properties
 D. Usachov, O. Vilkov, A. Grüneis, D. Haberer, A. Fedorov, V. K. Adamchuk, A. B. Preobrajenski, P. Dudin, A. Barinov, M. Oehzelt, C. Laubschat, and D. V. Vyalikh; Nano letters 11, 5401 (2011)
doi: 10.1021/nl2031037.
Last Updated on Wednesday, 11 November 2015 16:58