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The fascinating electrical and mechanical properties of single-walled carbon nanotubes (SWNT) have opened a great number of potential application for these unique materials. However, the high costs of the current production method and the difficulty in making them available for large-scale manufacturing can slow down the process of bringing this technology to commercial production.
To develop a cost-effective operation for the manufacture of SWNT a drastic change in the production scale is necessary.Following the original arc-discharge method, other synthesis methods have been investigated, including laser ablation, plasma discharge, and catalytic decomposition of carbon-containing gaseous. The catalytic method for production of nanotubes has been known for a long time, but this method typically results in production of multi-wall nanotubes (MWNT).
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At the University of Oklahoma we pointed out that the catalytic decomposition method was suitable for scaling up and for achieving a "controlled production" of SWNT. By this we implied the ability to control the selectivity towards SWNT by changing catalyst parameters and operating conditions, all combined with the ability to obtain a reliable quantitative measurement of the amount of SWNT produced.
For the last eight years we have been performing research on the development and optimization of a cost effective method that we named CoMoCAT process. Our expertise in heterogeneous catalysis allowed us to tailor the material in such a way that selectivity and yield are maximized. The method employed involves disproportionation of CO at moderate pressure and temperature, which results in a scalable, cost-effective process.
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Characterization on carbon nanotubes reveals distributions resolved at the level of individual (n,m) structures. Two structures, (6,5) and (7,5) together dominate the semiconducting nanotube distribution obtained by the CoMoCat process and comprise more than half of the population. Moreover, SEM and AFM analyses of parallel arrays of well aligned single-walled carbon nanotubes show that tubes are hundreds of microns long and are produced by decomposition of hydrocarbons on patterned metal lines evaporated over a quartz substrate.
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In a recent article from Chemical Physics Letters we reported the growth of conductive single-wall carbon nanotube (SWCNT) films with ultrahigh transparency (typically above 98% at 550 nm wavelength) on quartz substrates. Ferritin was used
as the catalyst precursor and ethanol as the carbon feed. The effects of experimental parameters on film
structure and performance have been investigated. Catalyst concentration and pre-annealing of the substrate
after catalyst deposition seem to be important parameters to optimize the resulting films. Analysis of these trends gives further insight into the mechanism of SWCNT film growth and termination, which may contribute to more effective synthesis of SWCNT films.
Droplets bounce off this nanotube surface. The contact angle with water is more than 165°. 
SWNT pillars prepared by nano-sphere lithography over a silicon wafer substrate. This surface is superhydrophobic.
Spectrofluorimetry result 
