Graphene-Induced Substrate Decoupling and Ideal Doping of a Self-Assembled Iron-phthalocyanine Single Layer

Iron-Phthalocyanine molecules self-assemble on the moiré pattern of graphene/Ir(111) as a flat and weakly interacting layer, as determined by core-level photoemission and absorptionspectroscopy. The graphene buffer layer decouples the FePc two-dimensional structure from the underlying metal, the electronic structure of the FePc molecular macrocycles is preserved, and the Fe-L2;3 edges present narrower and slightly modified resonances at the FePc singlelayer coverage with respect to a thin-film. The FePc layer induces a slight electron doping to the Ir-supported graphene resulting in the Dirac cone position expected for an ideal freestanding-like graphene layer with the standard Fermi velocity