Surface refinement and electronic properties of graphene layers grown on copper substrate: An XPS, UPS and EELS study

0362878 - ÚFCH JH 2012 RIV NL eng J - Journal Article
Siokou, A. - Ravani, F. - Karakalos, S. - Frank, Otakar - Kalbáč, Martin - Galiotis, C.
Surface refinement and electronic properties of graphene layers grown on copper substrate: An XPS, UPS and EELS study.
Applied Surface Science. Roč. 257, č. 23 (2011), s. 9785-9790. ISSN 0169-4332. E-ISSN 1873-5584
R&D Projects: GA MŠMT LC510; GA AV ČR IAA400400911
Institutional research plan: CEZ:AV0Z40400503
Keywords : graphene * XPS * EELS
Subject RIV: CG - Electrochemistry
Impact factor: 2.103, year: 2011

The present work focuses on the assessment of two surface treatment procedures employed under ultra high vacuum conditions in order to obtain atomically clean graphene layers without disrupting the morphology and the two dimensional character of the films. Graphene layers grown by chemical vapor deposition on polycrystalline Cu were stepwise annealed up to 750 °C or treated by mild Ar+ sputtering. The effectiveness of both methods and the changes that they induce on the surface morphology and electronic structure of the films were systematically studied by X-ray photoelectron spectroscopy, and electron energy loss spectroscopy. Ultraviolet photoelectron spectroscopy was employed for the study of the electronic properties of the as received sample and in combination with the work function measurements, indicated the hybridization of the C–π network with Cu d-orbitals. Mild Ar+ sputtering sessions were found to disrupt the sp2 network and cause amorphisation of the graphitic carbon.
Permanent Link: http://hdl.handle.net/11104/0006521