Doping Effects in Graphene Nanoribbons

  • Author: Liam Critchley
  • Published: 30 July 2018
  • Copyright: Wiley-VCH Verlag GmbH & Co. KGaA
  • Source / Publisher: Nano Letters/ACS Publications
  • Associated Societies: American Chemical Society (ACS), USA
thumbnail image: Doping Effects in Graphene Nanoribbons

Graphene nanoribbons (GNRs) are quasi-1D materials with potential applications in electronics. However, their electronic conductivity is much lower than that of 2D graphene sheets. Tailoring the structure through doping is seen as one way to improve the electrical properties of GNRs. Currently, doping mechanisms in GNRs are not well understood because the conventional doping models used for semiconductor materials are not applicable.


Felix R. Fischer, Steven G. Louie, Michael F. Crommie, University of California and Lawrence Berkeley National Laboratory, Berkeley, USA, and colleagues have studied the effects of boron dopants on the electronic structure of GNRs. The team synthesized GNRs with a maximum width of 7 carbon atoms (pictured) on an Au(111) surface using bottom-up deposition methods. The GNRs were then doped with boron at different concentrations using polymerization and cyclodehydrogenation approaches.


Using density functional theory (DFT) calculations, the team found that the inclusion of boron atoms into the GNRs should induce two sharp dopant electronic states, which vary in energy splitting values depending on the concentration of dopants. However, the observations from scanning tunneling spectroscopy experiments showed slightly different results, in that there were two broad dopant states with much higher energy splitting values than the calculations predicted.


According to the team, this higher energy split can be attributed to a unique hybridization between the dopant's electronic states and those of the underlying Au(111) surface. The researchers point out that they would expect a very different electronic behavior for boron-doped GNRs placed on substrates other than gold which interact less strongly with boron.


 

Article Views: 1226

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

Bookmark and Share

If you would like to reuse any content, in print or online, from ChemistryViews.org, please contact us first for permission. more


CONNECT:

ChemistryViews.org on Facebook

ChemistryViews.org on Twitter ChemistryViews.org on YouTube ChemistryViews.org on LinkedIn Sign up for our free newsletter


A product of ChemPubSoc Europe (16 European Chemical Societies)and Wiley-VCH