Nanotube electrical conductivity

If He or Ar is added to the vacuum chamber then metallic (electrical conducting) nanotubes are made in the majority this accounts for up to 91% of the nanotubes produced (Figure 14.8). 

The remarkable theoretical predictions mentioned above are even more difficult to verify by experimental measurements in the case of electrical conductivity. Ideally, one has to solve two experimental problems. First, one has to realize a four-point measurement on an individual nanotube. That means four contacts on a sample with typical dimensions of the order of a nm... 

The most promising way to study the electrical conductivity of a single nanotube is, thus, tightly dependent on the development or/and the adaptation of modern nanolithographic techniques. The goal to achieve is within reach and a detailed study of the electronic properties with reference to helicity and diameter will provide instrumental information about these fascinating materials. 

Carbon nanotubes are also of considerable interest with regard to both reinforcement and possible increases in electrical conductivity [237-239]. There is considerable interest in characterizing the flexibility of these nanotube structures, in minimizing their tendencies to aggregate, and in maximizing their miscibilities with organic and inorganic polymers. 

The orbital bonding nature within carbon nanotubes creates unique electrical properties within a non-metallic molecule, which is a result of the delocalization of the -electron donated by each atom. Electrical conductivity can take place along the entire nanotube due to the freedom of -electron flow, making possible the design of circuits of extremely low nanometer diameter. 

Meincke O, Kaempfer D, Weickmann H, Friedrich C, Vathauer M, Warth H (2004). Mechanical properties and electrical conductivity of carbon-nanotube filled polyamide-6 and its blends with acrylonitrile/butadiene/styrene. Polymer 45 739-748. 

Brown E, Hao L, Gallop JC, Macfarlane JC (2005) Ballistic thermal and electrical conductance measurements on individual multi wall carbon nanotubes. Applied Physics Letters 87 2-3. 

Dalmas F, Dendievel R, Chazeau L, Cavaille JY, Gauthier C (2006) Carbon nanotube-filled polymer of electrical conductivity in composites. Numerical simulation three-dimensional entangled fibrous networks. Acta Materialia 54 2923-2931. 

Y. Zhao, J. Wei, R. Vajtai, P. M. Ajayan, E. V. Barrera, Iodine doped carbon nanotube cables exceeding specific electrical conductivity of metals, Scientific Reports 1 83, 2011. 

V. Skakalova, A. B. Kaiser, U. Dettlaff-Weglikowska, K. Hrncarikova, S. Roth, Effect of chemical treatment on electrical conductivity, infrared absorption, and Raman spectra of single-walled carbon nanotubes, J. Phys. Chem. B, vol. 109, pp. 7174-7181, 2005. 

T. Tao, L. Zhang, J. Ma, C. Li, Production of flexible and electrically conductive polyethylene-carbon nanotube shish-kebab structures and their assembly into thin films, Ind. Eng. Chem. Res, vol. 51, pp. 5456-5460, 2012. 

R. H. Schmidt, I. A. Kinloch, A. N. Burgess, A. H. Windle, The effect of aggregation on the electrical conductivity of spin-coated polymer/carbon nanotube composite films, Langmuir, vol. 23, pp. 5707-5712, 2007. 

V. Tishkova, P.-l. Raynal, P. Puech, A. Lonjon, M. Le Fournier, P. Demont, E. Flahaut, W. Bacsa, Electrical conductivity and Raman imaging of double wall carbon nanotubes in a polymer matrix, Compos. Sci. Technol., vol. 71, pp. 1326-1330, 2011. 

J. S. Kim, S. J. Cho, K. S. Jeong, Y. C. Choi, M. S. Jeong, Improved electrical conductivity of very long multi-walled carbon nanotube bundle/poly (methyl methacrylate) composites, Carbon, vol. 49, pp. 2127-2133, 2011. 

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