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arXiv · 1107.0626

Ab initio calculations of edge-functionalized armchair graphene nanoribbons: Structural, electronic, and vibrational effects

Nils Rosenkranz·Christian Till·Christian Thomsen·Janina Maultzsch
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Abstract

We present a theoretical study on narrow armchair graphene nanoribbons (AGNRs) with hydroxyl functionalized edges. Although this kind of passivation strongly affects the structure of the ribbon, a high degree of edge functionalization proves to be particularly stable. An important consequence of the geometric deviations is a severe reduction of the band-gap of the investigated 7-AGNR. This shift follows a linear dependence on the number of added hydroxyl groups per unit cell and thus offers the prospect of a tunable band-gap by edge functionalization. We furthermore cover the behavior of characteristic phonons for the ribbon itself as well as fingerprint modes of the hydroxyl groups. A large down-shift of prominent Raman active modes allows the experimental determination of the degree of edge functionalization.

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Nils Rosenkranz, Christian Till, Christian Thomsen, Janina Maultzsch. 2011-07-04. Ab initio calculations of edge-functionalized armchair graphene nanoribbons: Structural, electronic, and vibrational effects. https://doi.org/10.1103/physrevb.84.195438

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