Intercalation of O$_2$ and N$_2$ in the Graphene/Ni Interfaces of Different Morphology

Near-ambient pressure XPS and STM experiments are performed to study the intercalation of oxygen and nitrogen at different partial gas pressures and different temperatures in the graphene/Ni/Ir(111) system of different morphologies. We performed detailed experiments on the investigation of the chemical state and topography of graphene, before and after gas intercalation, depending on the amount of pre-intercalated Ni in graphene/Ir(111). It is found that only oxygen can be intercalated under graphene in all considered cases, indicating the role of the intra-molecular bonding strength and possibility of gas molecules dissociation on different metallic surfaces on the principal possibility and on the mechanism of intercalation of different species under graphene.