Carbon nanotubes molecular arrays

Qi, P. Vermesh, O. Grecu, M. Javey, A. Wang, Q. Dai, H. Peng, S. Cho, K. J. 2003. Toward large arrays of multiplex functionalized carbon nanotube sensors for highly sensitive and selective molecular detection. Nano Lett. 3 347-351. 

Mesoporous alumina membranes ( anodic aluminium oxide , or AAO) are prepared by anodic oxidation of aluminium metal [1,2]. The cylindrical pores, perpendicular to the membrane surface, form hexagonal arrays of straight non-intersecting channels with pore densities up to lO Vcm. Their diameters are controllable within the range 5 - 100 nm as a linear function of anodisation voltage. These membranes are used as molecular sieves, and have also found application as templates for metallic nanowires [3,4,5,6], metal elusters and colloids [7,8], and carbon nanotubes [9,10]. 

Yin Y. F., Mays T. and McEnaney B., Molecular simulations of hydrogen storage in carbon nanotubes arrays. Langmuir 16 (2000) pp. 10521-10527. 

Zhang X. and Wang W., Methane adsorption in single-walled carbon nanotubes arrays by molecular simulation and density fimctional theory. Fluid Phase Equilibria 194-197 (2002) pp 289-295. 

The last example of these small-scale trace detectors is one based on nanotechnology platform and principles. This TSA funded project with NASA Ames Research Center involves the use of carbon nanotubes (CNT) as surface sensitive trace explosives sensors. In this case, the individual molecules of an explosive vapour interact on the atomic scale with a molecule(s) from the CNT surface. Figure 8 illustrates the NASA Ames conductive CNT explosives detector the CNT bridges between the source and drain of the transistor, and the change in conductance of the CNT bridge is measured as the molecular interaction with its surface (an array of CNT wires). 

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