Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Jefferson Lab’s Free-Electron Laser explores promise of carbon nanotubes

28.01.2003




Jefferson Lab’s Free-Electron Laser used to explore the fundamental science of how and why nanotubes form, paying close attention to the atomic and molecular details

Scientists and technologists of all stripes are working intensively to explore the possibilities of an extremely strong and versatile cylinder so tiny that millions -- which in bunches look like an ebony snowflake -- could fit easily on the tip of a pin. The objects in question are known as carbon nanotubes, first discovered in 1991 as the elongated form of an all-carbon molecule.

Sometimes called CNTs, nanotubes take up an extremely small space but can connect together materials with different properties, even as their own properties can be adjusted depending on formulation. The tubes’ "aspect ratio" is enormous: that is, they are very long but not wide, and like an ultra-strong rope, can be extended without sacrificing strength. CNTs have potential applications in molecular and quantum computing and as components for microelectromechanical sensors, or MEMS. The tubes could also function as a "lab on a chip," with attached microelectronics and components that could detect toxins and nerve agents in vanishingly small concentrations.



Nanotubes could also lead to an entirely new generation of materials: as strong or stronger than steel, but very lightweight. CNTs are amazingly damage-tolerant, generally displaying nearly total "elastic recovery," even under high-deformation conditions. If bent, buckled or creased the tubes are usually able to reassume their original shape once external stressors are removed.

"Nanotubes take up a very small amount of space but can connect a lot of material together," says Brian Holloway, an assistant professor in the College of William & Mary’s Department of Applied Science. "You can imagine replacing metal components with nanotubes that could weigh maybe a tenth as much. One of the big reasons NASA is interested is obviously because of the cost of getting to space."

A research team led by Holloway is also intrigued by the tubes’ potential. Holloway’s group has used Jefferson Lab’s Free-Electron Laser (FEL) to explore the fundamental science of how and why nanotubes form, paying close attention to the atomic and molecular details. Already, in experiments, the William & Mary/NASA Langley collaboration has produced tubes as good as if not better than those at other laboratories or in industry.

The next step will be to increase quantity while holding costs down, which Holloway believes will be possible using the Lab’s upgrade of the FEL to 10 kilowatts.

"Right now we’re interested in making more nanotubes," Holloway says. "The FEL offers a way to efficiently and cost-effectively make large amounts of high-quality tubes. Nanotubes come in a variety of flavors; the thought is we could eventually control what we call ’tube chiralities,’ [properties like] structure, length and diameter."

The CNT collaboration makes the tubes by striking a metal-impregnated carbon target with FEL light. The laser vaporizes layers of a graphite annulus, essentially a thick ring mounted on a spinning quartz rod. Atoms discharge from the annulus surface, creating a plume, a kind of nanotube "spray." Under the right conditions trillions upon trillions of nanotubes can be so formed within an hour.

Conventional means of nanotube production involves a tabletop laser. In this more traditional manufacturing approach, perhaps 10 milligrams -- about one-tenth of an aspirin-bottle full -- of the tubes can be produced per hour at costs up to $200 per gram. Conversely, with a one-kilowatt FEL, up to two grams per hour, or about 100 times more nanotubes can be made, at a cost of $100 per gram. A 10-kilowatt FEL could radically alter that equation. To that end, Holloway is seeking funding from NASA and the Office of Naval Research for a three-year project whose goal would be to optimize nanotube production with the upgraded FEL in order to manufacture large quantities quickly and cheaply.

According to Gwyn Williams, FEL Basic Research Program manager, researchers are anticipating learning much more about the details of the photochemical processes involved in nanotube production once the new FEL comes back on line in 2003. Demand for the tubes is intense and growing. Whoever finds a way to make them reliably and affordably could reap the rewards, financially and otherwise, as commercial interests beat a figurative path to researchers’ doors.

"A lot of people can make nanotubes. Very few can make grams or kilograms of nanotubes on time scales less than weeks," Holloway points out. "Factors other than price can drive demand. Right now there’s no one who could sell you one kilogram of nanotubes per month all of the same quality, at any price."

Linda Ware | EurekAlert!

More articles from Materials Sciences:

nachricht Physics, photosynthesis and solar cells
01.12.2016 | University of California - Riverside

nachricht New process produces hydrogen at much lower temperature
01.12.2016 | Waseda University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>