N-Doping of Graphene Through Electrothermal Reactions with Ammonia
Abstract
Graphene is readily p-doped by adsorbates, but for device applications, it would be useful to access the n-doped material. Individual graphene nanoribbons were covalently functionalized by nitrogen species through high-power electrical joule heating in ammonia gas, leading to n-type electronic doping consistent with theory. The formation of the carbon-nitrogen bond should occur mostly at the edges of graphene where chemical reactivity is high. X-ray photoelectron spectroscopy and nanometer-scale secondary ion mass spectroscopy confirm the carbon-nitrogen species in graphene thermally annealed in ammonia. We fabricated an n-type graphene field-effect transistor that operates at room temperature.
- Publication:
-
Science
- Pub Date:
- May 2009
- DOI:
- 10.1126/science.1170335
- Bibcode:
- 2009Sci...324..768W
- Keywords:
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- CHEMISTRY