Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stable electrodes for improving printed electronics

20.04.2012
Method could pave way for lower cost, more flexible devices

Imagine owning a television with the thickness and weight of a sheet of paper. It will be possible, someday, thanks to the growing industry of printed electronics. The process, which allows manufacturers to literally print or roll materials onto surfaces to produce an electronically functional device, is already used in organic solar cells and organic light-emitting diodes (OLEDs) that form the displays of cellphones.

Although this emerging technology is expected to grow by tens of billions of dollars over the next 10 years, one challenge is in manufacturing at low cost in ambient conditions. In order to create light or energy by injecting or collecting electrons, printed electronics require conductors, usually calcium, magnesium or lithium, with a low-work function. These metals are chemically very reactive. They oxidize and stop working if exposed to oxygen and moisture. This is why electronics in solar cells and TVs, for example, must be covered with a rigid, thick barrier such as glass or expensive encapsulation layers.

However, in new findings published in the journal Science, Georgia Tech researchers have introduced what appears to be a universal technique to reduce the work function of a conductor. They spread a very thin layer of a polymer, approximately one to 10 nanometers thick, on the conductor’s surface to create a strong surface dipole. The interaction turns air-stable conductors into efficient, low-work function electrodes.

The commercially available polymers can be easily processed from dilute solutions in solvents such as water and methoxyethanol.

“These polymers are inexpensive, environmentally friendly and compatible with existent roll-to-roll mass production techniques,” said Bernard Kippelen, director of Georgia Tech’s Center for Organic Photonics and Electronics (COPE). “Replacing the reactive metals with stable conductors, including conducting polymers, completely changes the requirements of how electronics are manufactured and protected. Their use can pave the way for lower cost and more flexible devices.”

To illustrate the new method, Kippelen and his peers evaluated the polymers’ performance in organic thin-film transistors and OLEDs. They’ve also built a prototype: the first-ever, completely plastic solar cell.

“The polymer modifier reduces the work function in a wide range of conductors, including silver, gold and aluminum,” noted Seth Marder, associate director of COPE and professor in the School of Chemistry and Biochemistry. “The process is also effective in transparent metal-oxides and graphene.”

COPE is a collaborative effort of Georgia Tech professors in the Colleges of Engineering, Sciences and the Ivan Allen College of Liberal Arts. The center is working on the next generation of electronic devices in order to save energy, reduce costs, increase national security and enhance the quality of the environment. Researchers from the groups of Georgia Tech professors Jean-Luc Brédas and Samuel Graham, as well as Princeton University Professor Antoine Kahn, also contributed to the new study.

The research was funded in part through the Center for Interface Science: Solar Electric Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001084, by the STC Program MDITR of the National Science Foundation under Agreement No. DMR-0120967, and by the Office of Naval Research (Grant No. N00014-04-1-0120). The content is solely the responsibility of the principal investigators and does not necessarily represent the official views of the DOE, NSF and ONR.

Jason Maderer | EurekAlert!
Further information:
http://www.gatech.edu

More articles from Power and Electrical Engineering:

nachricht Hot electrons harvested without tricks
18.11.2019 | University of Groningen

nachricht New laser opens up large, underused region of the electromagnetic spectrum
15.11.2019 | Harvard John A. Paulson School of Engineering and Applied Sciences

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Atoms don't like jumping rope

Nanooptical traps are a promising building block for quantum technologies. Austrian and German scientists have now removed an important obstacle to their practical use. They were able to show that a special form of mechanical vibration heats trapped particles in a very short time and knocks them out of the trap.

By controlling individual atoms, quantum properties can be investigated and made usable for technological applications. For about ten years, physicists have...

Im Focus: Images from NJIT's big bear solar observatory peel away layers of a stellar mystery

An international team of scientists, including three researchers from New Jersey Institute of Technology (NJIT), has shed new light on one of the central mysteries of solar physics: how energy from the Sun is transferred to the star's upper atmosphere, heating it to 1 million degrees Fahrenheit and higher in some regions, temperatures that are vastly hotter than the Sun's surface.

With new images from NJIT's Big Bear Solar Observatory (BBSO), the researchers have revealed in groundbreaking, granular detail what appears to be a likely...

Im Focus: New opportunities in additive manufacturing presented

Fraunhofer IFAM Dresden demonstrates manufacturing of copper components

The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM in Dresden has succeeded in using Selective Electron Beam Melting (SEBM) to...

Im Focus: New Pitt research finds carbon nanotubes show a love/hate relationship with water

Carbon nanotubes (CNTs) are valuable for a wide variety of applications. Made of graphene sheets rolled into tubes 10,000 times smaller than a human hair, CNTs have an exceptional strength-to-mass ratio and excellent thermal and electrical properties. These features make them ideal for a range of applications, including supercapacitors, interconnects, adhesives, particle trapping and structural color.

New research reveals even more potential for CNTs: as a coating, they can both repel and hold water in place, a useful property for applications like printing,...

Im Focus: Magnets for the second dimension

If you've ever tried to put several really strong, small cube magnets right next to each other on a magnetic board, you'll know that you just can't do it. What happens is that the magnets always arrange themselves in a column sticking out vertically from the magnetic board. Moreover, it's almost impossible to join several rows of these magnets together to form a flat surface. That's because magnets are dipolar. Equal poles repel each other, with the north pole of one magnet always attaching itself to the south pole of another and vice versa. This explains why they form a column with all the magnets aligned the same way.

Now, scientists at ETH Zurich have managed to create magnetic building blocks in the shape of cubes that - for the first time ever - can be joined together to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

First International Conference on Agrophotovoltaics in August 2020

15.11.2019 | Event News

Laser Symposium on Electromobility in Aachen: trends for the mobility revolution

15.11.2019 | Event News

High entropy alloys for hot turbines and tireless metal-forming presses

05.11.2019 | Event News

 
Latest News

The measurements of the expansion of the universe don't add up

19.11.2019 | Physics and Astronomy

Ayahuasca compound changes brainwaves to vivid 'waking-dream' state

19.11.2019 | Health and Medicine

Mantis shrimp vs. disco clams: Colorful sea creatures do more than dazzle

19.11.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>