• 文献标题:   Structural and Electronic Decoupling of C-60 from Epitaxial Graphene on
  • 文献类型:   Article
  • 作  者:   CHO J, SMERDON J, GAO L, SUZER O, GUEST JR, GUISINGER NP
  • 作者关键词:   graphene, c60 sic, scanning tunneling spectroscopy, stm, photovoltaic, charge transfer
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   CALTECH
  • 被引频次:   69
  • DOI:   10.1021/nl3008049
  • 出版年:   2012

▎ 摘  要

We have investigated the initial stages of growth and the electronic structure of C-60 molecules on graphene grown epitaxially on SiC(0001) at the single molecule level using cryogenic ultrahigh vacuum scanning tunneling microscopy and spectroscopy. We observe that the first layer of C-60 molecules self-assembles into a well-ordered, close-packed arrangement on graphene upon molecular deposition at room temperature while exhibiting a subtle C-60 superlattice. We measure a highest occupied molecular orbital-lowest unoccupied molecular orbital gap of similar to 3.S eV for the C-60 molecules on graphene in submonolayer regime, indicating a significantly smaller amount of charge transfer from the graphene to C-60 and substrate-induced screening as compared to C-60 adsorbed on metallic substrates. Our results have important implications for the use of graphene device applications that require electronic decoupling between functional molecular adsorbates and substrates.