Covalent Functionalization of Surfactant-Wrapped Graphene Nanoribbons

Using diazonium chemistry, two different covalent functionalization methods for graphene nanoribbons (GNRs) were developed. In addition to direct diazonium salt addition, which has been reported previously for functionalization of graphene sheets and single-walled carbon nanotubes, an in situ route using an organic nitrite was successfully applied. This new method broadens the possibilities of functionality type since anilines can be used instead of preprepared diazonium salts. The resulting functionalized GNRs (f-GNRs) are readily soluble in organic solvents such as N,N -dimethylformamide and N -methyl-2-pyrrolidinone, which increases their solution processability. The f-GNRs were also found to be in a reduced state, with minimal sp 2 carbon disruption, while keeping the ribbon shape. These organic-soluble ribbons might find applications in composites and thin film materials.