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This work demonstrates that photochemical doping of CVD-grown graphene can be easily achieved using photoacid (PAG) and photobase (PBG) generators such as triphenylsulfonium perfl uoro-1-butanesufonate (TPS-Nf ) and 2-nitrobenzyl N -cyclohexylcarbamate (NBC). The TPS-Nf ionic onium salt photoacid generator does not noticeably dope or alter the electrical properties of graphene when coated onto the graphene surface, but is very effective at inducing p-doping of graphene upon exposure of the PAG-coated graphene sample. Likewise, the neutral NBC photobase generator does not signifi cantly affect the electrical properties of graphene when coated, but upon exposure to ultraviolet light produces a free amine, which induces n-doping of the graphene. Electrical measurements show that the doping concentration can be modulated by controlling the deep ultraviolet (DUV) light exposure dose delivered to the sample. The interaction between both dopants and graphene is also investigated. The photochemical doping process is able to tune the work function of the single-layer graphene samples used in this work from 3.4 eV to 5.3 eV. Finally, a p-n junction is fabricated and analyzed, showing that it is possible to control the position of the two current minima (two Dirac points) in the ambipolar p-n junction.

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