Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Electrically conductive plastics promising for batteries, solar cells

10.10.2014

An emerging class of electrically conductive plastics called "radical polymers” may bring low-cost, transparent solar cells, flexible and lightweight batteries, and ultrathin antistatic coatings for consumer electronics and aircraft.

Researchers have established the solid-state electrical properties of one such polymer, called PTMA, which is about 10 times more electrically conductive than common semiconducting polymers.


An emerging class of electrically conductive plastics are called "radical polymers.” The graphic at left depicts the structure of a polymer. At right, transparent polymer overlays the Purdue logo. (Purdue University photo)

"It's a polymer glass that conducts charge, which seems like a contradiction because glasses are usually insulators," said Bryan Boudouris, an assistant professor of chemical engineering at Purdue University.

The polymer is easy to manufacture, resembling Plexiglas, an inexpensive transparent plastic found in numerous products. However, unlike Plexiglas it conducts electricity.

"We make billions of tons of plastic every year," Boudouris said. "So imagine if you could produce that same kind of material at that same scale but now it has electronic properties."

The PTMA is in a class of electrically active polymers that could bring inexpensive transparent solar cells; antistatic and antiglare coatings for cellphone displays; antistatic coverings for aircraft to protect against lightning strikes; flexible flash drives; and thermoelectric devices, which generate electricity from heat.

The polymers have seen commercial use in new types of batteries. However, finding widespread practical applications for the polymers will require increasing the conductivity another 100 to 1,000 times, Boudouris said.

Recent research findings were detailed in a paper published online in May in the journal Macromolecules. A review article on the subject appeared in September in the same journal and is featured on the cover. The American Chemical Society also has recorded a series of podcast with Boudouris, accessible at http://pubs.acs.org/page/mamobx/audio/index.html.

The review article is authored by Purdue graduate students Edward P. Tomlinson and Martha E. Hay, and Boudouris. The research article published in May was authored by graduate student Lizbeth Rostro, undergraduate student Si Hui Wong, and Boudouris.

Polymers are strings of molecules with a central backbone and may contain side chains called "pendant groups” that dangle from the central structure. In radical polymers, it's these pendant groups that allow charge to be transported, conducting current.

To create the radical polymer, the researchers used a procedure called deprotection, which involves replacing a specific hydrogen atom in the pendant group with an oxygen atom, converting it into a so-called radical group.

"We just finally studied deprotection in a way others had not to learn how it affects the electronic properties of the radical polymers,” Boudouris said.

Electrons surround an atom's nucleus in "shells," and these electrons are usually paired. The oxygen atom in PTMA, however, has one unpaired electron in its outer shell, making it amendable to transporting charge.

"You have to control the deprotection process very well because it makes the conductivity vary by orders of magnitude," he said.

The researchers have determined that the deprotection step can lead to four distinct chemical functionalities of the radical polymer, two of which are promising for increasing the conductivity of the polymer.

"So manipulating the reaction conditions for this deprotection step, and monitoring closely the resultant chemical functionalities, is critical in tuning the electrical properties of radical polymers,” Boudouris said.

The research is ongoing and has been funded by the National Science Foundation (NSF), the Air Force Office of Scientific Research (AFOSR) and the Defense Advanced Research Projects Agency (DARPA).    

Writer: Emil Venere, 765-494-4709, venere@purdue.edu 

Source: Bryan Boudouris, 765-496-6056, boudouris@purdue.edu 

ABSTRACT

Radical Polymers and Their Application to Organic Electronic Devices       

Edward P. Tomlinson , Martha E. Hay , and Bryan W. Boudouris *  

School of Chemical Engineering, Purdue University

Macromolecules, 2014, 47 (18), pp 6145–6158

*E-mail: boudouris@purdue.edu    

Macromolecules bearing stable radical groups have emerged as extremely useful active materials in organic electronic applications ranging from magnetic devices to flexible batteries. Critical to the success of these open-shell polymers has been the readily tunable nature of their molecular architectures; this important molecular structure–property–performance design paradigm has allowed for significant device performance metrics to be achieved. In this Perspective, the recent advancements regarding the design and device functionality of a common class of open-shell macromolecules, radical polymers, are discussed. Here, radical polymers are defined as macromolecules with nonconjugated carbon backbones, whose optoelectronic functionalities arise due to the presence of stable radical sites on the pendant groups of macromolecular chains. This class of materials provides a unique platform for the design of unique optical and electronic properties in soft materials; however, as with many organic electronic materials, transitioning these gains from the laboratory to the commercial scale remains a primary challenge. As such, we provide context for the significant accomplishments that have been made in the field, describe how these advances have been translated to high-performance devices, and discuss future areas of evaluation for these next-generation polymer electronic materials.

Emil Venere | idw - Informationsdienst Wissenschaft
Further information:
http://www.purdue.edu/newsroom/releases/2014/Q4/electrically-conductive-plastics-promising-for-batteries,-solar-cells.html

More articles from Power and Electrical Engineering:

nachricht Engineers program tiny robots to move, think like insects
15.12.2017 | Cornell University

nachricht Electromagnetic water cloak eliminates drag and wake
12.12.2017 | Duke University

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: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>