Single Walled Carbon Nanotubes (SWNTs) as a Gas Sensor

A thermoelectric “nano-nose” has been built from tangled bundles of single- walled carbon nanotubes (SWNT). The detector’s thermoelectric response [.Delta]S is sensitive to the logarithmic energy derivative of the additional bundle resistivity ([.rho]a) which is identified with the adsorbed molecules. The response is therefore specific to the details of the interaction of the adsorbed molecule with the nanotube wall; even gases such as He, N2 and H2 can be easily detected. Plots of [?]S vs. [?]a are sensitive to whether oxidation or reduction of the tube wall is taking place, and to whether the gas molecule is physisorbed or chemisorbed. The utility of the sensor stems from the amphoteric nature of the SWNT, the quasi-one-dimensional character of the charge conduction and the high specific surface area of SWNTs.

[1]  T. Ichihashi,et al.  Single-shell carbon nanotubes of 1-nm diameter , 1993, Nature.

[2]  Zettl,et al.  Extreme oxygen sensitivity of electronic properties of carbon nanotubes , 2000, Science.

[3]  Cheng,et al.  Hydrogen storage in single-walled carbon nanotubes at room temperature , 1999, Science.

[4]  Eklund,et al.  Effects of gas adsorption and collisions on electrical transport in single-walled carbon nanotubes , 2000, Physical review letters.

[5]  M. W. Cole,et al.  Hydrogen Adsorption in Nanotubes , 1998 .

[6]  Andrew G. Rinzler,et al.  FAR-INFRARED GAPS IN SINGLE-WALL CARBON NANOTUBES , 1999 .

[7]  Peter C. Eklund,et al.  Monte Carlo simulations of H2 physisorption in finite-diameter carbon nanotube ropes , 2000 .

[8]  K. Fukui,et al.  The Science and Technology of Carbon Nanotubes , 1999 .

[9]  A. M. Rao,et al.  Evidence for charge transfer in doped carbon nanotube bundles from Raman scattering , 1997, Nature.

[10]  Kong,et al.  Nanotube molecular wires as chemical sensors , 2000, Science.

[11]  Kenneth A. Smith,et al.  Hydrogen adsorption and cohesive energy of single-walled carbon nanotubes , 1999 .

[12]  M. S. de Vries,et al.  Cobalt-catalysed growth of carbon nanotubes with single-atomic-layer walls , 1993, Nature.

[13]  W. K. Maser,et al.  Large-scale production of single-walled carbon nanotubes by the electric-arc technique , 1997, Nature.

[14]  H. J. Kim,et al.  Conductivity enhancement in single-walled carbon nanotube bundles doped with K and Br , 1997, Nature.

[15]  Nobutsugu Minami,et al.  Pressure dependence of the optical absorption spectra of single-walled carbon nanotube films , 2000 .

[16]  L. B. Ebert.  Science of fullerenes and carbon nanotubes , 1996 .

[17]  Young Hee Lee,et al.  Crystalline Ropes of Metallic Carbon Nanotubes , 1996, Science.

[18]  Wen-Yuh Jywe,et al.  A method for evaluating the contour and tolerance of the toroidal cutter with helicoidal surfaces , 2000 .

[19]  M. Dresselhaus,et al.  Physical properties of carbon nanotubes , 1998 .

[20]  Peter C. Eklund,et al.  Low-temperature thermoelectrical power measurements using analogue subtraction , 2000 .

[21]  A. Halliday,et al.  Core formation on Mars and differentiated asteroids , 1997, Nature.

[22]  D. Bethune,et al.  Storage of hydrogen in single-walled carbon nanotubes , 1997, Nature.

[23]  P. Eklund,et al.  Thermoelectric power measurements using analog subtraction , 1977 .

[24]  Philip Kim,et al.  Structure and Electronic Properties of Carbon Nanotubes , 2000 .

[25]  Cohen,et al.  Electronic properties of oxidized carbon nanotubes , 2000, Physical review letters.

[26]  M. Dresselhaus,et al.  Phonons in carbon nanotubes , 2000 .