Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > UNC study on properties of carbon nanotubes, water could have wide-ranging implications

Abstract:
A fresh discovery about the way water behaves inside carbon nanotubes could have implications in fields ranging from the function of ultra-tiny high-tech devices to scientists' understanding of biological processes, according to researchers from the University of North Carolina at Chapel Hill.

UNC study on properties of carbon nanotubes, water could have wide-ranging implications

Chapel Hill, NC | Posted on October 2nd, 2008

The findings, published in the Oct. 3, 2008, issue of the journal Science, relate to a property of so-called "nano-confined" water - specifically, whether hollow carbon nanotubes take in the liquid easily or reluctantly, depending on their temperature.

As well as shedding light on the characteristics of human-made nanomaterials, researchers note that such properties are relevant to the workings of biological structures and phenomena which also function at nano-scales.

The team of scientists, led by Yue Wu, Ph.D., professor of physics in the UNC College of Arts and Sciences, examined carbon nanotubes measuring just 1.4 nanometers in diameter (one nanometer is a billionth of a meter). The seamless cylinders were made from rolled up graphene sheets, the exfoliated layer of graphite.

"Normally, graphene is hydrophobic, or 'water hating' - it repels water in the same way that drops of dew will roll off a lotus leaf," said Wu. "But we found that in the extremely limited space inside these tubes, the structure of water changes, and that it's possible to change the relationship between the graphene and the liquid to hydrophilic or 'water-liking'."

The UNC team did this by making the tubes colder. Using nuclear magnetic resonance - similar to the technology used in advanced medical MRI scanners - they found that at about room temperature (22 degrees centigrade), the interiors of carbon nanotubes take in water only reluctantly.

However, when the tubes were cooled to 8 degrees, water easily went inside. Wu said this shows that it is possible for water in nano-confined regions - either human-made or natural - to take on different structures and properties depending on the size of the confined region and the temperature.

In terms of potential practical applications, Wu suggested further research along these lines could impact the design of high-tech devices (for example, nano-fluidic chips that act as microscopic laboratories), microporous sorbent materials such as activated carbon used in water filters, gas masks, and permeable membranes.

"It may be that by exploiting this hydrophobic-hydrophilic transition, it might be possible to use changes in temperature as a kind of 'on-off' switch, changing the stickiness of water through nano-channels, and controlling fluid flow."

Wu also noted that this research relates to scientists' understanding of the workings of many building blocks of life (such as proteins, whose structures also have nano-confined hydrophobic regions) and how their interaction with water plays a role in how they function. For example, such interactions play an important role in the process known as "protein folding," which determines a protein's eventual shape and characteristics. Misfolded proteins are believed to be a cause of several neurodegenerative and other diseases.

"We don't fully understand the mechanisms behind protein unfolding upon cooling," Wu said. "Could this kind of cooling-induced hydrophobic-hydrophilic transition play a role? We don't know but it's worth investigating."

Along with Wu, the other study authors were graduate student Hai-Jing Wang, postdoctoral research associate Xue-Kui Xi, Ph.D., and research professor Alfred Kleinhammes, Ph.D., all from UNC.

####

For more information, please click here

Contacts:
Patric Lane

919-962-8596

Yue Wu, Ph.D.
(919) 962-0307

Copyright © University of North Carolina at Chapel Hill

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

World's fastest man-made spinning object could help study quantum mechanics July 20th, 2018

Relax, just break it July 20th, 2018

Future electronic components to be printed like newspapers July 20th, 2018

The relationship between charge density waves and superconductivity? It's complicated July 19th, 2018

Nanotubes/Buckyballs/Fullerenes/Nanorods

Carbon is the new black: Researchers use carbon nanotubes to develop clothing that can double as batteries July 10th, 2018

Nano-saturn: Supramolecular complex formation: Anthracene macrocycle and C60 fullerene June 8th, 2018

Unzipping graphene nanotubes into nanoribbons: New study shows elegant mathematical solution to understand how the flow of electrons changes when carbon nanotubes turn into zigzag nanoribbons June 6th, 2018

Making carbon nanotubes as usable as common plastics: Researchers discover that cresols disperse carbon nanotubes at unprecedentedly high concentrations May 15th, 2018

Discoveries

World's fastest man-made spinning object could help study quantum mechanics July 20th, 2018

Relax, just break it July 20th, 2018

Future electronic components to be printed like newspapers July 20th, 2018

The relationship between charge density waves and superconductivity? It's complicated July 19th, 2018

Announcements

World's fastest man-made spinning object could help study quantum mechanics July 20th, 2018

Relax, just break it July 20th, 2018

Future electronic components to be printed like newspapers July 20th, 2018

The relationship between charge density waves and superconductivity? It's complicated July 19th, 2018

Water

New sensor technology enables super-sensitive live monitoring of human biomolecules July 3rd, 2018

NIST Researchers Simulate Simple Logic for Nanofluidic Computing June 30th, 2018

Northwestern researchers achieve unprecedented control of polymer grids: Materials could find applications in water purification, solar energy storage, body armor June 22nd, 2018

Making quantum puddles: Physicists discover how to create the thinnest liquid films ever June 13th, 2018

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project