N-doping of graphene through electrothermal reactions with ammonia.
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.
Wang
Xinran
X
Department of Chemistry and Laboratory for Advanced Materials, Stanford University, Stanford, CA 94305, USA.
Li
Xiaolin
X
Zhang
Li
L
Yoon
Youngki
Y
Weber
Peter K
PK
Wang
Hailiang
H
Guo
Jing
J
Dai
Hongjie
H