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arXiv · 1412.8049

Raman spectroscopy at the edges of multilayer graphene

Q. -Q. Li·X. Zhang·W. -P. Han·Y. Lu·W. Shi·J. -B. Wu·P. -H. Tan
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Abstract

Edges naturally exist in a single-layer graphene sample. Similarly, individual graphene layers in a multilayer graphene sample contribute their own edges. We study the Raman spectrum at the edge of a graphene layer laid on n layer graphene (nLG). We found that the D band observed from the edge of the top graphene layer exhibits an identical line shape to that of disordered (n+1)LG induced by ion-implantation. Based on the spectral features of the D and 2D bands, we identified two types of alignment configurations at the edges of mechanically-exfoliated bilayer and trilayer graphenes, whose edges are well-aligned from their optical images.

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Q. -Q. Li, X. Zhang, W. -P. Han, Y. Lu, W. Shi, J. -B. Wu, P. -H. Tan. 2014-12-27. Raman spectroscopy at the edges of multilayer graphene. https://doi.org/10.1016/j.carbon.2014.12.096

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