Nitro
gen dopin
g of
graphene is of
great interest for both fundamental research to explore the effect of dopants on a 2D electrical conductor and applications such as lithium stora
ge, composites, and nanoelectronic devices. Here, we report on the modifications of the electronic properties of epitaxial
graphene thanks to the introduction, durin
g the
growth, of nitro
gen-atom substitution in the carbon honeycomb lattice. Hi
gh-resolution transmission microscopy and low-ener
gy electron microscopy investi
gations indicate that the nitro
gen-doped
graphene is uniform at lar
ge scale. The substitution of nitro
gen atoms in the
graphene planes was confirmed by hi
gh-resolution X-ray photoelectron spectroscopy, which reveals several atomic confi
gurations for the nitro
gen atoms:
graphitic-like, pyridine-like, and pyrrolic-like. An
gle-resolved photoemission measurements show that the N-doped
graphene exhibits lar
ge n-type carrier concentrations of 2.6 脳 10
13 cm
鈥?, about 4 times more than what is found for pristine
graphene,
grown under similar pressure conditions. Our experiments demonstrate that a small amount of dopants (<1%) can si
gnificantly tune the electronic properties of
graphene by shiftin
g the Dirac cone about 0.3 eV toward hi
gher bindin
g ener
gies with respect to the 蟺 band of pristine
graphene, which is a key feature for envisionin
g applications in nanoelectronics.
Keywords:
g/action/doSearch?action=search&searchText=epitaxial+graphene&qsSearchArea=searchText">epitaxial graphene; g/action/doSearch?action=search&searchText=spectroscopy&qsSearchArea=searchText">spectroscopy; g/action/doSearch?action=search&searchText=nitrogen%5C-doped&qsSearchArea=searchText">nitrogen-doped; g/action/doSearch?action=search&searchText=low%5C-energy+electron+microscopy&qsSearchArea=searchText">low-energy electron microscopy; g/action/doSearch?action=search&searchText=electronic+properties&qsSearchArea=searchText">electronic properties