What is microscopic and huge all at once? It's the carbon nanotube, a minute filament that has big implications for both William and Mary and Associate Professor of Applied Science Brian Holloway.
The nanotube, a quasi one-dimensional, molecular, tube-shaped structure is comprised of amorphous carbon similar to that in pencil lead. Due in large part to its carbon-carbon bonds, the carbon nanotube is one of the strongest substances available to man and therefore ideal for all sorts of technological applications.
Professor of Applied Science Brian Holloway is researching how to cheaply produce nanotubes for NASA.
Photo courtesy of Holloway.
Although nanotubes themselves are not new formations, it is the innovative method by which Holloway is producing them, employing a free electron laser previously used in silicon defect and biomedical research, which is generating interest.
"Other people use lasers. We are the first to use the free electron laser. It's like if other people were the first to go 200 miles per hour in a car, but we were the first to do it in a Chevy," said Holloway.
Holloway's project has received funding from the Defense Advanced Research Project Agency (DARPA) in the Department of Defense and has attracted the attention of NASA, with NASA material scientist Mike Smith also doing research on the project.
Because of the novel method by which these nanotubes are being produced, a process patent can be obtained and the patent then sold. William and Mary, however, would retain the license, creating a lucrative proposition for the College. According to a recent article about Holloway's research in the Daily Press, there are already 15 commercial nanotube producers worldwide.
Due to the nanotube's strength and extreme light weight, it can potentially be substituted for current materials used in rockets and satellites, saving thousands of dollars per pound during launching. Nanotubes also have great potential for unmanned aerial vehicles and fuel cells, among other uses.
The commercialization of nanotubes produced via free electron laser, Holloway predicts, is still at least five years down the road. Although Holloway and his fellow researchers have proved that nanotubes can be created by free electron lasers, more work must first be done to find the optimum parameter for production before an economically viable quantity can be made.
Right now the laser being used, which is located at Jefferson Lab in Newport News, is research grade and allows for a wide range of parameters.
"An analogy would be if there were a delivery van with leather seats, cruise control, AM/FM radio, CD with 6 tracks, surround sound and cool pen striping down the side," explained Holloway. "We don't need this for commercial production. What we need is a stick shift [...] optimized to do what we want it to do."
Because what is yielded from the laser does not consist of purely nanotubes, analysis is being conducted and the parameters on the laser adjusted in an attempt to produce a larger percent of nanotubes per yield.
In addition to quandaries within the commercial arena of nanotube production, the research being conducted is also meant to help elucidate how and why nanotubes form in the first place, an issue which has yet to be resolved.
Another aspect of research that is performed, mainly by NASA, pertains to the use of appropriate binders with the nanotubes. The nanotubes, Holloway explains, provide strength in the same manner that a cloth covered in glue would. Glue by itself, like the binder, is rigid and rips. Just as a cloth would provide toughness to the glue, so too do the nanotubes provide toughness to the binder. Instead of a mere cotton fiber cloth, however, the nanotubes consist of carbon fibers woven together, making them the strongest thing known to humanity.
Submitted: Thursday, April 15, 2004 - 12:00am