Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Gecko's lessons transfer well

Forests of nanotubes grown via chemical vapor deposition are treated with hydrogen gas and water to loosen their bonds with a catalyst. They can then be transferred to another surface, just like a rubber stamp.
Forests of nanotubes grown via chemical vapor deposition are treated with hydrogen gas and water to loosen their bonds with a catalyst. They can then be transferred to another surface, just like a rubber stamp.

Abstract:
Dry printing of nanotube patterns to any surface could revolutionize microelectronics and more

Gecko's lessons transfer well

Houston, TX | Posted on January 23rd, 2010

Watch a gecko walk up a wall. It defies gravity as it sticks to the surface no matter how smooth it appears to be.

What's happening isn't magic. The gecko stays put because of the electrical attraction - the van der Waals force - between millions of microscopic hairs on its feet and the surface.

The principle applies to new research at Rice University reported this week in the online version of the journal ACS Nano. But in this case, the hairs figuratively come off the gecko and plant themselves on the wall.

Rice graduate student Cary Pint has come up with a way to transfer forests of strongly aligned, single-walled carbon nanotubes (SWNTs) from one surface to another - any surface - in a matter of minutes. The template used to grow the nanotubes, with its catalyst particles still intact, can be used repeatedly to grow more nanotubes, almost like inking a rubber stamp.

Pint is primary author of the research paper, which also details a way to quickly and easily determine the range of diameters in a batch of nanotubes grown through chemical vapor deposition (CVD). Common spectroscopic techniques are poor at seeing tubes bigger than two nanometers in diameter - or most of the nanotubes in the CVD "supergrowth" process.

"This is important since all of the properties of the nanotubes - electrical, thermal and mechanical - change with diameter," he said. "The best thing is that nearly every university has an FTIR (Fourier transform infrared) spectrometer sitting around that can do these measurements, and that should make the process of synthesis and application development from carbon nanotubes much more precise."

Pint and other students and colleagues of Robert Hauge, a Rice distinguished faculty fellow in chemistry, are also investigating ways to take printed films of SWNTs and make them all-conducting or all-semiconducting - a process Hauge refers to as "Fermi-level engineering" for its ability to manipulate electron movement at the nanoscale.

Combined, the techniques represent a huge step toward a nearly limitless number of practical applications that include sensors, highly efficient solar panels and electronic components.

"A big frontier for the field of nanoscience is in finding ways to make what we can do on the nanoscale impact our everyday activities," Hauge said. "For the use of carbon nanotubes in devices that can change the way we do things, a straightforward and scalable way of patterning aligned carbon nanotubes over any surface and in any pattern is a major advance."

Pint said an afternoon of "experimenting with creative ideas" as a first-year graduate student turned into a project that held his interest through his time at Rice. "I realized early on it may be useful to transfer carbon nanotubes to other surfaces," he said.

"I started playing around with water vapor to clean up the amorphous carbons on the nanotubes. When I pulled out a sample, I noticed the nanotubes actually stuck to the tweezers.

"I thought to myself, 'That's really interesting ...'"

Water turns out to be the key. After growing the nanotubes, Pint etches them with a mix of hydrogen gas and water vapor, which weakens the chemical bonds between the tubes and the metal catalyst. When stamped, the nanotubes lie down and adhere, via van der Waals, to the new surface, leaving all traces of the catalyst behind.

Pint, who hopes to defend his dissertation in August, developed a steady enough hand to deposit nanotubes on a range of surfaces - "anything I could lay my hands on" - in patterns that could easily be replicated and certainly enhanced by industrial processes. A striking example of his work is a crisscross film of nanotubes made by stamping one set of lines onto a surface and then reusing the catalyst to grow more tubes and stamping them again over the first pattern at a 90-degree angle. The process took no more than 15 minutes.

"I'll be honest - that was a little bit of luck, combined with the skill of having done this for a few years," he said of the miniature work of art. "But if I were in industry, I would make a machine to do this for me."

Pint believes industries will take a hard look at the technique, which he said could be scaled up easily, for embedding nanotube circuitry into electronic devices.

His own goal is to develop the process to make a range of highly efficient sensing devices. He's also investigating doping techniques that will take the guesswork out of growing metallic (conducting) or semiconducting SWNTs.

Pint and Hauge co-authored the paper with Junichiro Kono, a Rice professor in electrical and computer engineering and in physics and astronomy; Matteo Pasquali, a professor in chemical and biomolecular engineering; former Rice graduate students Ya-Qiong Xu, now an assistant professor of electrical engineering and physics at Vanderbilt University, and Tonya Cherukuri; graduate students Noe Alvarez and Erik Haroz; undergraduate students Sharief Moghazy and Salma Mahzooni; and Stephen Doorn, a researcher at Los Alamos National Laboratory.

The Rice-based Lockheed Martin LANCER program supported the research.

####

For more information, please click here

Contacts:
Jade Boyd
Associate Director /Science Editor
713-348-6778

Copyright © Rice University

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

Starpharma initiates new DEPô drug delivery program with AstraZeneca July 27th, 2016

Ageing can drive progress: Population ageing is likely to boost medicine, nanotechnology and robotics, but increase political risks July 27th, 2016

WSU researchers 'watch' crystal structure change in real time: Breakthrough made possible by new Argonne facility July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

Possible Futures

Ageing can drive progress: Population ageing is likely to boost medicine, nanotechnology and robotics, but increase political risks July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

New lithium-oxygen battery greatly improves energy efficiency, longevity: New chemistry could overcome key drawbacks of lithium-air batteries July 26th, 2016

Chip Technology

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

Nanometrics Reports Second Quarter 2016 Financial Results July 26th, 2016

Ultra-flat circuits will have unique properties: Rice University lab studies 2-D hybrids to see how they differ from common electronics July 25th, 2016

Attosecond physics: Mapping electromagnetic waveforms July 25th, 2016

Nanotubes/Buckyballs/Fullerenes

Easier, faster, cheaper: A full-filling approach to making nanotubes of consistent quality: Approach opens a straightforward route for engineering the properties of single-wall carbon nanotubes July 19th, 2016

Sensing trouble: A new way to detect hidden damage in bridges, roads: University of Delaware engineers devise new method for monitoring structural health July 8th, 2016

Wireless, wearable toxic-gas detector: Inexpensive sensors could be worn by soldiers to detect hazardous chemical agents July 4th, 2016

Nanotubes' 'stuffing' as is: A scientist from the Lomonosov Moscow State University studied the types of carbon nanotubes' 'stuffing' June 2nd, 2016

Sensors

Ultrasensitive sensor using N-doped graphene July 26th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Electron 'spin control' of levitated nanodiamonds could bring advances in sensors, quantum information processing July 20th, 2016

Easier, faster, cheaper: A full-filling approach to making nanotubes of consistent quality: Approach opens a straightforward route for engineering the properties of single-wall carbon nanotubes July 19th, 2016

Nanoelectronics

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

Ultra-flat circuits will have unique properties: Rice University lab studies 2-D hybrids to see how they differ from common electronics July 25th, 2016

Borrowing from pastry chefs, engineers create nanolayered composites: Method to stack hundreds of nanoscale layers could open new vistas in materials science July 25th, 2016

Making magnets flip like cats at room temperature: Heusler alloy NiMnSb could prove valuable as a new material for digital information processing and storage July 25th, 2016

Discoveries

WSU researchers 'watch' crystal structure change in real time: Breakthrough made possible by new Argonne facility July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

Ultrasensitive sensor using N-doped graphene July 26th, 2016

Announcements

Starpharma initiates new DEPô drug delivery program with AstraZeneca July 27th, 2016

Ageing can drive progress: Population ageing is likely to boost medicine, nanotechnology and robotics, but increase political risks July 27th, 2016

WSU researchers 'watch' crystal structure change in real time: Breakthrough made possible by new Argonne facility July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

Solar/Photovoltaic

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

Researchers discover key mechanism for producing solar cells: Better understanding of perovskite solar cells could boost widespread use July 21st, 2016

The future of perovskite solar cells has just got brighter -- come rain or shine: Korean researchers at POSTECH have succeeded in developing high-efficiency perovskite solar cells that retain excellent performance over two months in a very humid condition July 21st, 2016

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic