Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

’Nano skins’ show promise as flexible electronic devices

02.03.2006


A team of researchers has developed a new process to make flexible, conducting ’nano skins’ for a variety of applications, from electronic paper to sensors for detecting chemical and biological agents. The materials, which are described in the March issue of the journal Nano Letters, combine the strength and conductivity of carbon nanotubes with the flexibility of traditional polymers.


A flexible, conducting "nano skin" with organized arrays of nanotubes embedded throughout. Credit: Rensselaer/Yung Joon Jung



"Researchers have long been interested in making composites of nanotubes and polymers, but it can be difficult to engineer the interfaces between the two materials," says Pulickel Ajayan, the Henry Burlage Professor of Materials Science and Engineering at Rensselaer Polytechnic Institute. "We have found a way to get arrays of nanotubes into a soft polymer matrix without disturbing the shape, size, or alignment of the nanotubes."

Nanotube arrays typically don’t maintain their shape when transferred because they are held together by weak forces. But the team has developed a new procedure that allows them to grow an array of nanotubes on a separate platform and then fill the array with a soft polymer. When the polymer hardens, it is essentially peeled back from the platform, leaving a flexible skin with organized arrays of nanotubes embedded throughout.


The skins can be bent, flexed, and rolled up like a scroll, all while maintaining their ability to conduct electricity, which makes them ideal materials for electronic paper and other flexible electronics, according to Ajayan.

"The general concept (growing nanotubes on a stiff platform in various organizations, and then transferring them to a flexible platform without losing this organization) could have many other applications, all the way from adhesive structures and Velcro-like materials to nanotube interconnects for electronics," says Swastik Kar, a postdoctoral researcher in materials science and engineering at Rensselaer and lead author of the paper, along with Yung Joon Jung, assistant professor of mechanical and industrial engineering at Northeastern University and a recent doctoral student in Ajayan’s Rensselaer lab.

For example, with researchers at the University of Akron, Ajayan is using a similar process to mimic the agile gecko, with its uncanny ability to run up walls and across ceilings. The team recently reported a process for creating artificial gecko feet with 200 times the sticking power of the real thing, using nanotubes to imitate the thousands of microscopic hairs on a gecko’s footpad. Ajayan’s team is also working with Ali Dhinojwala, associate professor of polymer science at Akron, to develop a range of products with nanotubes and flexible substrates.

The researchers also envision using the process to build miniature pressure sensors and gas detectors. "There are a lot of possibilities if you have an easy way to transfer the nanotubes to any platform, and that is what we have developed," Ajayan says.

The team has shown that the flexible materials demonstrate an extremely useful physical property called "field emission." When a voltage is applied to certain materials, electrons are pulled out from the surface, which can be used to produce high-resolution electronic displays. "Nanotubes are very good field emitters because they have a low threshold for emission and they produce high currents," Kar says. "But when you lay nanotubes very close to each other, each tube tends to shield its neighbor from the electric field."

This effect has limited the development of field emission devices based on densely packed, aligned nanotubes, but it seems to go away when the nanotubes are embedded in a polymer, according to Kar. Tests showed that the team’s "nano skins" are excellent field emitters when compared to some of the best values obtained by other research groups.

Jason Gorss | EurekAlert!
Further information:
http://www.rpi.edu

More articles from Materials Sciences:

nachricht Osaka university researchers make the slipperiest surfaces adhesive
18.10.2017 | Osaka University

nachricht Think laterally to sidestep production problems
17.10.2017 | King Abdullah University of Science & Technology (KAUST)

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Osaka university researchers make the slipperiest surfaces adhesive

18.10.2017 | Materials Sciences

Space radiation won't stop NASA's human exploration

18.10.2017 | Physics and Astronomy

Los Alamos researchers and supercomputers help interpret the latest LIGO findings

18.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>