Nitrogen-doped graphene: beyond single substitution and enhanced molecular sensing.
Graphene is a two-dimensional network in which sp(2)-hybridized carbon atoms are arranged in two different triangular sub-lattices (A and B). By incorporating nitrogen atoms into graphene, its physico-chemical properties could be significantly altered depending on the doping configuration within the sub-lattices. Here, we describe the synthesis of large-area, highly-crystalline monolayer N-doped graphene (NG) sheets via atmospheric-pressure chemical vapor deposition, yielding a unique N-doping site composed of two quasi-adjacent substitutional nitrogen atoms within the same graphene sub-lattice (N(2)(AA)). Scanning tunneling microscopy and spectroscopy (STM and STS) of NG revealed the presence of localized states in the conduction band induced by N(2)(AA)-doping, which was confirmed by ab initio calculations. Furthermore, we demonstrated for the first time that NG could be used to efficiently probe organic molecules via a highly improved graphene enhanced Raman scattering.
Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA.
Ruitao
R
Lv
Qing
Q
Li
Andrés R
AR
Botello-Méndez
Takuya
T
Hayashi
Bei
B
Wang
Ayse
A
Berkdemir
Qingzhen
Q
Hao
Ana Laura
AL
Elías
Rodolfo
R
Cruz-Silva
Humberto R
HR
Gutiérrez
Yoong Ahm
YA
Kim
Hiroyuki
H
Muramatsu
Jun
J
Zhu
Morinobu
M
Endo
Humberto
H
Terrones
Jean-Christophe
JC
Charlier
Minghu
M
Pan
Mauricio
M
Terrones
D004563:Electrochemistry; D006108:Graphite / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D009584:Nitrogen / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D013059:Spectrum Analysis, Raman
D006108:Graphite; D009584:Nitrogen