• 文献标题:   Atmospheric Oxygen Binding and Hole Doping in Deformed Graphene on a SiO2 Substrate
  • 文献类型:   Article
  • 作  者:   RYU S, LIU L, BERCIAUD S, YU YJ, LIU HT, KIM P, FLYNN GW, BRUS LE
  • 作者关键词:   graphene, raman spectroscopy scanning tunneling microscopy stm chemical doping ripple oxygen
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984
  • 通讯作者地址:   Columbia Univ
  • 被引频次:   502
  • DOI:   10.1021/nl1029607
  • 出版年:   2010

▎ 摘  要

Using micro Raman spectroscopy and scanning tunneling microscopy we study the relationship between structural distortion and electrical hole doping of graphene on a silicon dioxide substrate The observed upshift of the Raman G band represents charge doping and not compressive strain Two independent factors control the doping (1) the degree of graphene coupling to the substrate and (2) exposure to oxygen and moisture Thermal annealing induces a pronounced structural distortion due to close coupling to SiO2 and activates the ability of diatomic oxygen to accept charge from graphene Gas flow experiments show that dry oxygen reversibly dopes graphene doping becomes stronger and more irreversible in the presence of moisture and over long periods of. time We propose that oxygen molecular anions are stabilized by water solvation and electrostatic binding to the silicon dioxide surface