▎ 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.