Adsorption properties of CoPc molecule on epitaxial graphene/Ru(0001)

作者:Cai, Yiliang; Zhang, Hanjie; Song, Junjie; Zhang, Yuxi; Bao, Shining; He, Pimo*
来源:Applied Surface Science, 2015, 327: 517-522.
DOI:10.1016/j.apsusc.2014.11.184

摘要

Combining the scanning tunneling microscopy (STM) and density functional theory (DFT), the adsorption properties of cobalt phthalocyanine (CoPc) on monolayer graphene/Ru(0 0 0 1) [MG/Ru(0 0 0 1)] have been investigated. At monolayer coverage, CoPc forms an ordered Kagome lattice, and a slight deformation for one lobe of CoPc and charge transfer from CoPc to Ru(0 0 0 1) substrate take place. The existence of the defect (vacancy) in graphene on Ru(0 0 0 1) increases the coupling between the Ru substrate and the epitaxial graphene. Such an increase of the coupling brings about an overall CoPc molecular energy level shift toward the low binding energy, which subsequently results in a central topographical contrast between the CoPc molecules on the intact and defective MG/Ru(0 0 0 1).