Intrinsic response of graphene vapor sensors.

Graphene is a two-dimensional material with extremely favorable chemical sensor properties. Conventional nanolithography typically leaves a resist residue on the graphene surface, whose impact on the sensor characteristics has not yet been determined. Here we show that the contamination layer chemically dopes the graphene, enhances carrier scattering, and acts as an absorbent layer that concentrates analyte molecules at the graphene surface, thereby enhancing the sensor response. We demonstrate a cleaning process that verifiably removes the contamination on the device structure and allows the intrinsic chemical responses of the graphene monolayer to be measured. These intrinsic responses are surprisingly small, even upon exposure to strong analytes such as ammonia vapor.

[1]  T. Mallouk,et al.  Gas sensing properties of single conducting polymer nanowires and the effect of temperature , 2008, Nanotechnology.

[2]  William A. Goddard,et al.  Peptide-nanowire hybrid materials for selective sensing of small molecules. , 2008, Journal of the American Chemical Society.

[3]  J. Kysar,et al.  Measurement of the Elastic Properties and Intrinsic Strength of Monolayer Graphene , 2008, Science.

[4]  F. Peeters,et al.  Paramagnetic adsorbates on graphene: a charge transfer analysis , 2008, 0806.0549.

[5]  P. Kim,et al.  Temperature-dependent transport in suspended graphene. , 2008, Physical review letters.

[6]  A. Bachtold,et al.  The environment of graphene probed by electrostatic force microscopy , 2008, 0803.2032.

[7]  Feng Wang,et al.  Gate-Variable Optical Transitions in Graphene , 2008, Science.

[8]  G. Fudenberg,et al.  Ultrahigh electron mobility in suspended graphene , 2008, 0802.2389.

[9]  Kengo Shimanoe,et al.  Theory of power laws for semiconductor gas sensors , 2008 .

[10]  S. Xiao,et al.  Intrinsic and extrinsic performance limits of graphene devices on SiO2. , 2007, Nature nanotechnology.

[11]  K. Novoselov,et al.  Giant intrinsic carrier mobilities in graphene and its bilayer. , 2007, Physical review letters.

[12]  F. M. Peeters,et al.  Adsorption of H 2 O , N H 3 , CO, N O 2 , and NO on graphene: A first-principles study , 2007, 0710.1757.

[13]  K. Novoselov,et al.  Molecular doping of graphene. , 2007, Nano letters.

[14]  S. Xiao,et al.  Intrinsic and extrinsic performance limits of graphene devices on SiO 2 , 2008 .

[15]  A. Bachtold,et al.  Current-induced cleaning of graphene , 2007, 0709.0607.

[16]  F. Beltram,et al.  The optical visibility of graphene: interference colors of ultrathin graphite on SiO(2). , 2007, Nano letters.

[17]  E. Williams,et al.  Atomic structure of graphene on SiO2. , 2007, Nano letters.

[18]  T. Mallouk,et al.  Dielectrophoretically assembled polymer nanowires for gas sensing , 2007, cond-mat/0702619.

[19]  Andre K. Geim,et al.  The rise of graphene. , 2007, Nature materials.

[20]  K. Novoselov,et al.  Detection of individual gas molecules adsorbed on graphene. , 2006, Nature materials.

[21]  Andre K. Geim,et al.  Raman spectrum of graphene and graphene layers. , 2006, Physical review letters.

[22]  A. Geim,et al.  Two-dimensional gas of massless Dirac fermions in graphene , 2005, Nature.

[23]  Alan Gelperin,et al.  DNA-decorated carbon nanotubes for chemical sensing , 2005, Nano letters.

[24]  M. Radosavljevic,et al.  Nonvolatile Molecular Memory Elements Based on Ambipolar Nanotube Field Effect Transistors , 2002, cond-mat/0206392.

[25]  Michael S. Fuhrer,et al.  High-Mobility Nanotube Transistor Memory , 2002 .

[26]  Hongjie Dai,et al.  Full and Modulated Chemical Gating of Individual Carbon Nanotubes by Organic Amine Compounds , 2001 .

[27]  Pietro Siciliano,et al.  Tin oxide-based gas sensors prepared by the sol–gel process , 1997 .