Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Role of Precursor Carbides for Graphene Growth on Ni(111)


Rameshan,  Raffael
Inorganic Chemistry, Fritz Haber Institute, Max Planck Society;
Institute of Physical Chemistry, University of Innsbruck;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)

(Publisher version), 4MB

Supplementary Material (public)
There is no public supplementary material available

Rameshan, R., Vonk, V., Frank, D., Drnec, J., Penner, S., Garhofer, A., et al. (2018). Role of Precursor Carbides for Graphene Growth on Ni(111). Scientific Reports, 8: 2662. doi:10.1038/s41598-018-20777-4.

Cite as: https://hdl.handle.net/21.11116/0000-0000-B5B0-C
Surface X-ray Diffraction was used to study the transformation of a carbon-supersaturated carbidic precursor toward a complete single layer of graphene in the temperature region below 703 K without carbon supply from the gas phase. The excess carbon beyond the 0.45  monolayers of C atoms within a single Ni2C layer is accompanied by sharpened reflections of the |4772| superstructure, along with ring-like diffraction features resulting from non-coincidence rotated Ni2C-type domains. A dynamic Ni2C reordering process, accompanied by slow carbon loss to subsurface regions, is proposed to increase the Ni2C 2D carbide long-range order via ripening toward coherent domains, and to increase the local supersaturation of near-surface dissolved carbon required for spontaneous graphene nucleation and growth. Upon transformation, the intensities of the surface carbide reflections and of specific powder-like diffraction rings vanish. The associated change of the specular X-ray reflectivity allows to quantify a single, fully surface-covering layer of graphene (2 ML C) without diffraction contributions of rotated domains. The simultaneous presence of top-fcc and bridge-top configurations of graphene explains the crystal truncation rod data of the graphene-covered surface. Structure determination of the |4772| precursor surface-carbide using density functional theory is in perfect agreement with the experimentally derived X-ray structure factors.