ARPES on graphene domains grown on industrially relevant substrates

A real space map of graphene grain orientation on the copper foil visualized through photoemission microscopy with integrated intensity from around the Dirac point of a specific orientation. The two colors, red and blue, correspond to signal from two different graphene orientations.
N. Wilson et al, Nano Research 6, 99-112, (2013)

Here we find an epitaxial relationship between graphene and copper foil. Interfacial restructuring between graphene and copper drives the formation of (n10) facets on what is otherwise a mostly Cu(100) surface, and the facets in turn influence the graphene orientations from the onset of growth. Angle resolved photoemission shows that the electronic structure of the graphene is decoupled from the copper indicating a weak interaction between them. Despite this, two preferred orientations of graphene are found, ±8° from the Cu[010] direction, creating a non-uniform distribution of graphene grain boundary misorientation angles. Comparison with the model system of graphene growth on single crystal Cu(110) indicates that this orientational alignment is due to mismatch epitaxy. Despite the differences in symmetry the orientation of the graphene is defined by that of the copper.

We expect these observations to not only have importance for controlling and understanding the growth process for graphene on copper, but also to have wider implications for the growth of two-dimensional materials on low cost metal substrates.

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Weak mismatch epitaxy and structural Feedback in graphene growth on copper foil, N. Wilson et al, Nano Research ASAP, doi 10.1007/s12274-013-0285-y(2013)

Last Updated on Tuesday, 24 November 2015 16:53