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

作者:Rosenkranz Nils*; Till Christian; Thomsen Christian; Maultzsch Janina
来源:Physical Review B, 2011, 84(19): 195438.
DOI:10.1103/PhysRevB.84.195438

摘要

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, i.e., a high ratio of edge atoms being hydroxylized, 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 downshift of prominent Raman active modes allows the experimental determination of the degree of edge functionalization.

  • 出版日期2011-11-9