Optical Properties of Graphene Nanoflakes: Shape Matters

Abstract

In recent years there has been significant debate on whether the edge type of graphene nanoflakes (GNF) or graphene quantum dots (GQD) are relevant for their electronic structure, thermal stability and optical properties. Using computer simulations, we have proven that there is a fundamental difference in the calculated absorption spectra between samples of the same shape, similar size but different edge type, namely, armchair or zigzag edges. These can be explained by the presence of electronic structures near the Fermi level which are localized on the edges. These features are also evident from the dependence of band gap on the GNF size, which shows three very distinct trends for different shapes and edge geometries.

8 pages, 9 figures. Submitted to The Journal of Chemical Physics

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Cited by in corpus (6)

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• Coronene: a model for ultrafast dynamics in graphene nanoflakes and PAHs
• The Correlated Electronic States of a few Polycyclic Aromatic Hydrocarbons: A Computational Study
• Emergent scale invariance of non-classical plasmons in graphene nanoribbons
• Tailoring the opto-electronic response of graphene nanoflakes by size and shape optimization