Featured Research

from universities, journals, and other organizations

Oxygen 'sponge' presents path to better catalysts, energy materials

Date:
August 28, 2013
Source:
Oak Ridge National Laboratory
Summary:
Scientists have developed a new oxygen “sponge” that can easily absorb or shed oxygen atoms at low temperatures. Materials with these novel characteristics would be useful in devices such as rechargeable batteries, sensors, gas converters and fuel cells.

This schematic depicts a new ORNL-developed material that can easily absorb or shed oxygen atoms.
Credit: Image courtesy of Oak Ridge National Laboratory

Scientists at the Department of Energy's Oak Ridge National Laboratory have developed a new oxygen "sponge" that can easily absorb or shed oxygen atoms at low temperatures. Materials with these novel characteristics would be useful in devices such as rechargeable batteries, sensors, gas converters and fuel cells.

Materials containing atoms that can switch back and forth between multiple oxidation states are technologically important but very rare in nature, says ORNL's Ho Nyung Lee, who led the international research team that published its findings in Nature Materials.

"Typically, most elements have a stable oxidation state, and they want to stay there," Lee said. "So far there aren't many known materials in which atoms are easily convertible between different valence states. We've found a chemical substance that can reversibly change between phases at rather low temperatures without deteriorating, which is a very intriguing phenomenon."

Many energy storage and sensor devices rely on this valence-switching trick, known as a reduction-oxidation or "redox" reaction. For instance, catalytic gas converters use platinum-based metals to transform harmful emissions such as carbon monoxide into nontoxic gases by adding oxygen. Less expensive oxide-based alternatives to platinum usually require very high temperatures -- at least 600 to 700 degrees Celsius -- to trigger the redox reactions, making such materials impractical in conventional applications.

"We show that our multivalent oxygen sponges can undergo such a redox process at as low as 200 degrees Celsius, which is comparable to the working temperature of noble metal catalysts," Lee said. "Granted, our material is not coming to your car tomorrow, but this discovery shows that multivalent oxides can play a pivotal role in future energy technologies."

The team's material consists of strontium cobaltite, which is known to occur in a preferred crystalline form called brownmillerite. Through an epitaxial stabilization process, the ORNL-led team discovered a new recipe to synthesize the material in a more desirable phase known as perovskite. The researchers have filed an invention disclosure on their findings.

"These two phases have very distinct physical properties," Lee said. "One is a metal, the other is an insulator. One responds to magnetic fields, the other does not -- and we can make it switch back and forth within a second at significantly reduced temperatures."

The international team's design and testing of this novel advanced material from scratch required multidisciplinary expertise and sophisticated tools from such places as Argonne National Laboratory and ORNL, including Argonne's Advanced Photon Source and ORNL's Center for Nanophase Materials Science, says Lee.

"As we showed in this study, only through the study of a well-defined system can we build a framework for the design of next generation energy materials," said coauthor John Freeland of Argonne. "This insight was made possible by merging the capabilities at Oak Ridge and Argonne national labs for advanced synthesis and characterization of novel materials."


Story Source:

The above story is based on materials provided by Oak Ridge National Laboratory. Note: Materials may be edited for content and length.


Journal Reference:

  1. Hyoungjeen Jeen, Woo Seok Choi, Michael D. Biegalski, Chad M. Folkman, I-Cheng Tung, Dillon D. Fong, John W. Freeland, Dongwon Shin, Hiromichi Ohta, Matthew F. Chisholm, Ho Nyung Lee. Reversible redox reactions in an epitaxially stabilized SrCoOx oxygen sponge. Nature Materials, 2013; DOI: 10.1038/nmat3736

Cite This Page:

Oak Ridge National Laboratory. "Oxygen 'sponge' presents path to better catalysts, energy materials." ScienceDaily. ScienceDaily, 28 August 2013. <www.sciencedaily.com/releases/2013/08/130828172823.htm>.
Oak Ridge National Laboratory. (2013, August 28). Oxygen 'sponge' presents path to better catalysts, energy materials. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2013/08/130828172823.htm
Oak Ridge National Laboratory. "Oxygen 'sponge' presents path to better catalysts, energy materials." ScienceDaily. www.sciencedaily.com/releases/2013/08/130828172823.htm (accessed October 22, 2014).

Share This



More Matter & Energy News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Internet of Things Aims to Smarten Your Life

Internet of Things Aims to Smarten Your Life

AP (Oct. 22, 2014) As more and more Bluetooth-enabled devices are reaching consumers, developers are busy connecting them together as part of the Internet of Things. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Newsy (Oct. 21, 2014) If you've ever watched "Back to the Future Part II" and wanted to get your hands on a hoverboard, well, you might soon be in luck. Video provided by Newsy
Powered by NewsLook.com
Robots to Fly Planes Where Humans Can't

Robots to Fly Planes Where Humans Can't

Reuters - Innovations Video Online (Oct. 21, 2014) Researchers in South Korea are developing a robotic pilot that could potentially replace humans in the cockpit. Unlike drones and autopilot programs which are configured for specific aircraft, the robots' humanoid design will allow it to fly any type of plane with no additional sensors. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins