Selective n-type doping of graphene by photo-patterned gold nanoparticles.

Selective n-type doping of graphene is developed by utilizing patternable gold nanoparticles functionalized with photoreactive cinnamate moieties. The gold nanoparticles can be regularly patterned on the graphene by UV-induced cross-linking of cinnamate, which provides a convenient method to control the optical and electrical properties of graphene site-specifically. The strong n-type doping of graphene covered with the patterned gold nanoparticles was confirmed by Raman, X-ray photoelectron spectroscopy, and electron transport measurements. We believe that our method would find numerous applications in the area of graphene-based optoelectronics including light-emitting devices, solar cells, and optical sensors.