File Download

  • Find it @ UNIST can give you direct access to the published full text of this article. (UNISTARs only)
Related Researcher

김광수

Kim, Kwang S.
Read More

Views & Downloads

Detailed Information

Cited time in webofscience Cited time in scopus
Metadata Downloads

Quasi-Free-Standing Graphene Monolayer on a Ni Crystal through Spontaneous Na Intercalation

Author(s)
Park, Young S.Park, Jae H.Hwang, Han N.Laishram, Tomba SinghKim, Kwang S.Kang, Myung H.Hwang, Chan C.
Issued Date
2014-07
DOI
10.1103/PhysRevX.4.031016
URI
https://scholarworks.unist.ac.kr/handle/201301/7722
Citation
PHYSICAL REVIEW X, v.4, no.3, pp.031016
Abstract
Graphene on metal substrates often shows different electronic properties from isolated graphene because of graphene-substrate interactions. One needs to remove the metals with acids and then to transfer graphene to weakly interacting substrates to recover electrical properties inherent in graphene. This process is not easy and besides causes undesirable tears, defects, and impurities in graphene. Here, we report a method to recover the electronic structure of graphene from a strongly interacting Ni substrate by spontaneous Na intercalation. In order to characterize the intercalation process, the density-functional-theory calculations and angle-resolved photoemission-spectroscopy (ARPES) and scanning-tunneling-microscopy (STM) measurements are carried out. From the density-functional-theory calculations, Na atoms energetically prefer interface intercalation to surface adsorption for the graphene/Ni(111) surface. Unlike most intercalants, Na atoms intercalate spontaneously at room temperature due to a tiny diffusion barrier, which is consistent with our temperature-dependent ARPES and core-level photoemission spectroscopy, and with our submonolayer ARPES and STM results at room temperature. As a result of the spontaneous intercalation, the electronic structure of graphene is almost recovered, as confirmed by the Dirac cone with a negligible band gap in ARPES and the sixfold symmetry in STM.
Publisher
American Physical Society
ISSN
2160-3308

qrcode

Items in Repository are protected by copyright, with all rights reserved, unless otherwise indicated.