A novel strategy for efficient growth of nitrogen-doped graphene (N-graphene) on a large scale from s-triazine molecules is presented. The growth process has been unveiled in situ using time-dependent photoemission. It has been established that a postannealing of N-graphene after gold intercalation causes a conversion of the N environment from pyridinic to graphitic, allowing to obtain more than 80% of all embedded nitrogen in graphitic form, which is essential for the electron doping in graphene. A band gap, a doping level of 300 meV, and a charge-carrier concentration of ∼8×10(12) electrons per cm2, induced by 0.4 atom % of graphitic nitrogen, have been detected by angle-resolved photoemission spectroscopy, which offers great promise for implementation of this system in next generation electronic devices.

We report on angle-resolved photoemission studies of the electronic pi states of high-quality epitaxial graphene layers on a Ni(111) surface. In this system the electron binding energy of the pi states shows a strong dependence on the magnetization reversal of the Ni film. The observed extraordinarily large energy shift up to 225 meV of the graphene-derived pi band peak position for opposite magnetization directions is attributed to a manifestation of the Rashba interaction between spin-polarized electrons in the pi band and the large effective electric field at the graphene/Ni interface. Our findings show that an electron spin in the graphene layer can be manipulated in a controlled way and have important implications for graphene-based spintronic devices.

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Here we report the photoemission studies of intercalation process of Fe underneath graphene layer on Ni(111). The process of intercalation was monitored via XPS of corresponding core levels and UPS of the graphene-derived π states in the valence band. fcc-Fe films with thickness of 2-5 monolayers at the interface between graphene and Ni(111) form epitaxial magnetic layer passivated from the reactive environment, like for example oxygen gas.

We report on an investigation of spin-polarized secondary electron emission from the chemically inert system: graphene/Ni(111). An ordered passivated graphene layer (monolayer of graphite, MG) was formed on Ni(111) surface via cracking of propylene gas. The spin-polarization of the secondary electrons obtained from this system upon photoemission is only slightly lower than the one from the clean Ni surface, but does not change upon large oxygen exposure. These results suggest to use such passivated Ni(111) surface as a source of spin-polarized electrons stable against adsorption of reactive gases.