▎ 摘　　要

The effect of nitrogen doping on graphene was characterized without exposing the prepared specimen to the atmosphere. Nitrogen doping was done via a photochemical process at room temperature, in which graphene on SiO2/Si was irradiated by UV light in ammonia. Field effect transistor measurements revealed that the UV-irradiation of graphene in NH3 causes electron doping of similar to 10(12) cm(-2) (similar to 0.01%) as a result of N-doping, which can be controlled by changing the irradiation time. Comparing the transfer characteristics and the Raman spectra, we discuss the structure of the graphene functionalized via photochemical reactions, and the corresponding electronic structure.