We report on simultaneous thermoelectric power and four-probe resistance measurements of chemical vapor deposition grown graphene during a degas process, as well as in exposure to various gases. For all investigated samples, a dramatic change in thermoelectric power was observed and found to be sensitive to the gas molecule charge doping on the surface of graphene. The observed p-type behavior under ambient conditions supports an electrochemical charge transfer mechanism between the graphene and oxygen redox couple, while the n-type behavior under degassed conditions is ascribed to the electron doping caused by the surface states of the SiO2/Si substrate.
REFERENCES
1.
F.
Schedin
, A. K.
Geim
, S. V.
Morozov
, E. W.
Hill
, P.
Blake
, M. I.
Katsnelson
, and K. S.
Novoselov
, Nature Mater.
6
, 652
(2007
).2.
T.
Lohmann
, K.
von Klitzing
, and J. H.
Smet
, Nano Lett.
9
, 1973
(2009
).3.
H. E.
Romero
, N.
Shen
, P.
Joshi
, H. R.
Gutierrez
, S. A.
Tadigadapa
, J. O.
Sofo
, and P. C.
Eklund
, ACS Nano
2
, 2037
(2008
).4.
J. H.
Chen
, C.
Jang
, S. D.
Xiao
, M.
Ishigami
, and M. S.
Fuhrer
, Nat. Nanotechnol.
3
, 206
(2008
).5.
S. V.
Morozov
, K. S.
Novoselov
, M. I.
Katsnelson
, F.
Schedin
, D. C.
Elias
, J. A.
Jaszczak
, and A. K.
Geim
, Phys. Rev. Lett.
100
, 016602
(2008
).6.
X. S.
Li
, W. W.
Cai
, J. H.
An
, S.
Kim
, J.
Nah
, D. X.
Yang
, R.
Piner
, A.
Velamakanni
, I.
Jung
, E.
Tutuc
, S. K.
Banerjee
, L.
Colombo
, and R. S.
Ruoff
, Science
324
, 1312
(2009
).7.
H. L.
Cao
, Q. K.
Yu
, L. A.
Jauregui
, J.
Tian
, W.
Wu
, Z.
Liu
, R.
Jalilian
, D. K.
Benjamin
, Z.
Jiang
, J.
Bao
, S. S.
Pei
, and Y. P.
Chen
, Appl. Phys. Lett.
96
, 122106
(2010
).8.
G. U.
Sumanasekera
, L.
Grigorian
, and P. C.
Eklund
, Meas. Sci. Technol.
11
, 273
(2000
).9.
See supplementary material at http://dx.doi.org/10.1063/1.3609858 for measurement details.
10.
Y. M.
Zuev
, W.
Chang
, and P.
Kim
, Phys. Rev. Lett.
102
, 096807
(2009
).11.
P.
Wei
, W.
Bao
, Y.
Pu
, C. N.
Lau
, and J.
Shi
, Phys. Rev. Lett.
102
, 166808
(2009
).12.
J. G.
Checkelsky
and N. P.
Ong
, Phys. Rev. B
80
, 081413
(2009
).13.
G. U.
Sumanasekera
, C. K. W.
Adu
, S.
Fang
, and P. C.
Eklund
, Phys. Rev. Lett.
85
, 1096
(2000
).14.
V.
Derycke
, R.
Martel
, J.
Appenzeller
, and P.
Avouris
, Nano Lett.
1
, 453
(2001
).15.
V.
Chakrapani
, J. C.
Angus
, A. B.
Anderson
, S. D.
Wolter
, B. R.
Stoner
, and G. U.
Sumanasekera
, Science
318
, 1424
(2007
).16.
W. Y.
Zhang
, J.
Ristein
, and L.
Ley
, Phys. Rev. E
78
, 041603
(2008
).17.
C. M.
Aguirre
, P. L.
Levesque
, M.
Paillet
, F.
Lapointe
, B. C.
St-Antoine
, P.
Desjardins
, and R.
Martel
, Adv. Mater.
21
, 3087
(2009
).18.
P. L.
Levesque
, S. S.
Sabri
, C. M.
Aguirre
, J.
Guillemette
, M.
Siaj
, P.
Desjardins
, T.
Szkopek
, and R.
Martel
, Nano Lett.
11
, 132
(2010
).19.
Y.-J.
Yu
, Y.
Zhao
, S.
Ryu
, L. E.
Brus
, K. S.
Kim
, and P.
Kim
, Nano Lett.
9
, 3430
(2009
).20.
E. H.
Hwang
and S.
Das Sarma
, Phys. Rev. B
79
, 165404
(2009
).21.
E. H.
Hwang
, E.
Rossi
, and S.
Das Sarma
, Phys. Rev. B
80
, 235415
(2009
).22.
J.
Kong
, N. R.
Franklin
, C.
Zhou
, M. G.
Chapline
, S.
Peng
, K.
Cho
, and H.
Dai
, Science
287
, 622
(2000
).23.
O.
Leenaerts
, B.
Partoens
, and F. M.
Peeters
, Phys. Rev. B
77
, 125416
(2008
).© 2011 American Institute of Physics.
2011
American Institute of Physics
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