Edges bring new dimension to graphene nanoribbons.
Chemistry at the edges of saturated graphene nanoribbons can cause ribbons to leave the plane and form three-dimensional helical structures. Calculations, based on density functional theory and enabled by adopting helical symmetry, show that F-terminated armchair ribbons are intrinsically twisted in helices, unlike flat H-terminated strips. Twisting ribbons of either termination couple the conduction and valence bands, resulting in band gap modulation. This electromechanical response could be exploited in switches and sensor applications.
Gunlycke
Daniel
D
Chemistry Division, Naval Research Laboratory, Washington, District of Columbia 20375, USA. gunlycke.sw@nrl.navy.mil
Li
Junwen
J
Mintmire
John W
JW
White
Carter T
CT