Graphene nanoribbons exfoliated from graphite surface dislocation bands by electrostatic force.

We have developed a novel technique to produce long and narrow graphene ribbons with smooth edges. This technique is free of any chemical treatments and involves a combination of two steps: (i) creation of surface dislocation ribbons by high velocity clusters impacting the graphite surface and (ii) electrostatic transferring of the dislocation ribbons to a desired substrate. The width of the ribbons can be controlled by varying the impact velocity of a cluster jet stream from a gas jet impactor. The electrical transport properties were investigated on the ribbons in field effect transistor (FET) configuration. The p-type behavior observed under ambient conditions was found to be reversed upon annealing at 180 degrees C in a vacuum of 10( - 7) Torr. Charge transfer effects were observed when the degassed graphene was exposed to N(2)O and NH(3).