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arXiv · 0810.5358

Raman Spectroscopy of Graphene Edges

C. Casiraghi·A. Hartschuh·H. Qian·S. Piscanec·C. Georgi·K. S. Novoselov·D. M. Basko·A. C. Ferrari
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Abstract

Graphene edges are of particular interest, since their chirality determines the electronic properties. Here we present a detailed Raman investigation of graphene flakes with well defined edges oriented at different crystallographic directions. The position, width and intensity of G and D peaks at the edges are studied as a function of the incident light polarization. The D-band is strongest for light polarized parallel to the edge and minimum for perpendicular orientation. Raman mapping shows that the D peak is localized in proximity of the edge. The D to G ratio does not always show a significant dependence on edge orientation. Thus, even though edges can appear macroscopically smooth and oriented at well defined angles, they are not necessarily microscopically ordered.

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C. Casiraghi, A. Hartschuh, H. Qian, S. Piscanec, C. Georgi, K. S. Novoselov, D. M. Basko, A. C. Ferrari. 2008-10-29. Raman Spectroscopy of Graphene Edges. https://doi.org/10.1021/nl8032697

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