• 文献标题:   Electronic structure of graphene/TiO2 interface: Design and functional perspectives
  • 文献类型:   Article
  • 作  者:   MISHRA SB, ROY SC, NANDA BRK
  • 作者关键词:   interface electronic structure, bandgap, charge transfer, dipolar field, strain
  • 出版物名称:   APPLIED SURFACE SCIENCE
  • ISSN:   0169-4332 EI 1873-5584
  • 通讯作者地址:  
  • 被引频次:   6
  • DOI:   10.1016/j.apsusc.2020.148709
  • 出版年:   2021

▎ 摘  要

We propose the design of low strained and energetically favourable mono and bilayer graphene overlayer on anatase TiO2 (001) surface and examined the electronic structure of the interface with the aid of first principle calculations. In the absence of hybridization between surface TiO2 and graphene states, dipolar fluctuations govern the minor charge transfer across the interface. As a result, both the substrate and the overlayer retain their pristine electronic structure. The interface with the monolayer graphene retains its gapless linear band dispersion irrespective of the induced epitaxial strain. The potential gradient opens up a few meV bandgap in the case of Bernal stacking and strengthens the interpenetration of the Dirac cones in the case of hexagonal stacking of the bilayer graphene. The difference between the macroscopic average potential of the TiO2 and graphene layer(s) in the heterostructure lies in the range 3-3.13 eV, which is very close to the TiO2 bandgap ((similar to)3.2 eV). Therefore, the proposed heterostructure will exhibit enhanced photo-induced charge transfer and the graphene component will serve as a visible light sensitizer.