Graphene nanoribbons (also called nano-graphene ribbons), often abbreviated gnrs, are thin strips of graphene or unrolled single-walled carbon nanotubes. The graphene ribbons were originally introduced as a theoretical model by Mitsutaka Fujita et.al. To examine the edge and nanoscale size effect in graphene. Their electronic states largely depend on the edge structures (armchair or zigzag). Zigzag edges provide the edge localized state with non-bonding molecular orbitals near the Fermi energy. They are expected to have large changes in optical and electronic properties from quantization.

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