• 文献标题:   Periodic Modulation of Graphene by a 2D-FeO/Ir(111) Moire Interlayer
  • 文献类型:   Article
  • 作  者:   MA YJ, TRAVAGLIA E, BANA H, BIGNARDI L, LACOVIG P, LIZZIT S, BATZILL M
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF PHYSICAL CHEMISTRY C
  • ISSN:   1932-7447
  • 通讯作者地址:   Univ S Florida
  • 被引频次:   2
  • DOI:   10.1021/acs.jpcc.6b11112
  • 出版年:   2017

▎ 摘  要

Ultrathin films of iron oxide form a two-dimensional (2D) FeO layer on Ir(111). Because of difference in lattice constant between 2D-FeO and Ir(111), a moire superstructure is formed. The 2D-FeO/Ir(111) structure is examined by soft X-ray photoelectron spectroscopy, X-ray photoemission diffraction, scanning tunneling microscopy, and low-energy electron diffraction. A 2D-FeO layer may also be grown by iron intercalation and subsequent oxidation underneath a graphene layer on Ir(111). Thus, the graphene can be decoupled from the metal by the 2D-FeO layer. Changes in the graphene C is binding energy can be mainly explained by shifts in the Fermi level of graphene as a consequence of interface band alignment for weak interactions between graphene and the substrate. A shift of C Is to lower binding energy, for graphene supported on FeO/Ir(111), is a consequence of the dipole moment in the 2D-FeO layer normal to the Ir(111) surface. Broadening of the C Is peak is consistent with a locally varying 2D-FeO dipole within the moire structure and thus implies a modulated charge doping of the graphene.