  Anchoring various functional groups to graphene is the most versatile
approach for tailoring its functional properties. To date, one must use a
special tunneling microscope for attaching a molecule at a specific position on
the graphene with resolution better than several hundred nanometers, however,
achieving this resolution is impossible on a large scale. We demonstrate for
the first time that chemical functionalization can be achieved with nanometer
resolution by introducing strain with nanometer scale modulation into a
graphene layer. The spatial distribution of the strain has been achieved by
transferring a single-layer graphene (SLG) onto a substrate decorated by a few
nm large nanoparticles (NPs). By changing the number of NPs on the substrate,
the amount of locally strained SLG increases, as confirmed by atomic force
microscopy (AFM) and Raman spectroscopy investigations. We further carried out
hydrogenation and fluorination on the SLG with increasing amount of nanoscale
corrugations. Raman spectroscopy, AFM and X-ray photoelectron spectroscopy
revealed unambiguously that the level of functionalization increases
proportionally with the number of NPs, which means an increasing number of the
locally strained SLG. Our approach thus enables control of the amount and the
position of functional groups on graphene with nanometer resolution.

Materials Science;Other Condensed Matter