Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Team takes first atomic-scale compositional images of fuel-cell nanoparticles

Left image highlights two platinum-cobalt catalyst nanoparticles (inside the dashed boxes) with a 'sandwich' structure of platinum and cobalt atoms near the surface. At right is a cross-sectional model corresponding to the lower particle, showing platinum atoms enriched in the outermost layer, cobalt enriched in the second, and additional layers containing a mixture of the two. (Image at left taken at Oak Ridge National Laboratory.) Image courtesy / Electrochemical Energy Laboratory at MIT
Left image highlights two platinum-cobalt catalyst nanoparticles (inside the dashed boxes) with a 'sandwich' structure of platinum and cobalt atoms near the surface. At right is a cross-sectional model corresponding to the lower particle, showing platinum atoms enriched in the outermost layer, cobalt enriched in the second, and additional layers containing a mixture of the two. (Image at left taken at Oak Ridge National Laboratory.) Image courtesy / Electrochemical Energy Laboratory at MIT

Abstract:
Work could lead to better catalysts for eco-friendly energy storage devices

Team takes first atomic-scale compositional images of fuel-cell nanoparticles

Cambridge, MA | Posted on October 2nd, 2008

In a step toward developing better fuel cells for electric cars and more, engineers at MIT and two other institutions have taken the first images of individual atoms on and near the surface of nanoparticles key to the eco-friendly energy storage devices.

Nanoparticles made of platinum and cobalt are known to catalyze some of the chemical reactions behind fuel cells, making those reactions run up to four times faster than if platinum alone is used as the catalyst.

No one, however, understands exactly why. That's because "little is known about the nanoparticles' surface atomic structure and chemistry," which are key to the particles' activity, said Yang Shao-Horn, an associate professor in the Department of Mechanical Engineering and Department of Materials Science and Engineering and director of the Electrochemical Energy Laboratory at MIT.

Using a new technique known as aberration-corrected Scanning Transmission Electron Microscopy, Shao-Horn's team, in collaboration with Professor Paulo Ferreira of the University of Texas at Austin and Dr. Larry Allard of Oak Ridge National Laboratory, identified specific atomic structures near the surface of such a catalyst. That information in hand, the researchers propose a theory for why the material is so active. Perhaps most importantly, "knowing the surface composition will help us design even better catalysts," Shao-Horn said.

The work was reported in the Sept. 24 online issue of the Journal of the American Chemical Society.

The researchers analyzed platinum and cobalt nanoparticles that were either treated with acid, or treated with acid then subjected to high heat. Nanoparticles produced both ways are known to be more active than platinum alone. Shao-Horn and colleagues found that each, in turn, also had slightly different surface structures.

For example, in the nanoparticles subjected to heat treatments, the platinum and cobalt atoms formed a "sandwich-like" structure. Platinum atoms covered most of the surface, while the next layer down was composed primarily of cobalt. Successive layers contained mixtures of the two.

The team proposes that these particular nanoparticles are up to four times more active than platinum alone because the platinum atoms on the surface are constrained by the cobalt atoms underneath. "This modifies the interatomic distances between the platinum atoms on the nanoparticle surface," making them more effective in chemical reactions key to fuel cells, Shao-Horn said.

She further noted that "this work bridges the gap between our understanding of electrocatalysis in bulk materials and at the nano-scale."

In addition to Shao-Horn, Allard, and Ferreira, who is also an MIT research affiliate, other members of the research team are Shuo Chen, first author of the paper and a postdoctoral associate in mechanical engineering; Wenchao Sheng, a graduate student in chemistry; and Naoaki Yabuuchi, a research affiliate in mechanical engineering.

The Department of Energy and the National Science Foundation, through its Materials Research Science and Engineering Center program, funded the work.

####

About MIT
The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the 21st century.

For more information, please click here

Contacts:
Teresa Herbert
MIT News Office
Phone: 617-258-5403

Copyright © MIT

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

Scientists synthesize nanoparticle-antioxidants to treat strokes and spinal cord injuries January 16th, 2018

New catalyst for hydrogen production is a step toward clean fuel: Carbon-based nanocomposite with embedded metal ions yields impressive performance as catalyst for electrolysis of water to generate hydrogen January 16th, 2018

'Gyroscope' molecules form crystal that's both solid and full of motion: New type of molecular machine designed by UCLA researchers could have wide-ranging applications in technology and science January 16th, 2018

The nanoscopic structure that locks up our genes January 16th, 2018

New exotic phenomena seen in photonic crystals: Researchers observe, for the first time, topological effects unique to an “open” system January 12th, 2018

Imaging

The nanoscopic structure that locks up our genes January 16th, 2018

Silver nanoparticles take spectroscopy to new dimension: A new way of organizing nanostructures has boosted Raman signals by a hundred thousand times to better identify and characterize different molecules January 2nd, 2018

Viewing atomic structures of dopant atoms in 3-D relating to electrical activity in a semiconductor December 28th, 2017

Discoveries

Scientists synthesize nanoparticle-antioxidants to treat strokes and spinal cord injuries January 16th, 2018

New catalyst for hydrogen production is a step toward clean fuel: Carbon-based nanocomposite with embedded metal ions yields impressive performance as catalyst for electrolysis of water to generate hydrogen January 16th, 2018

'Gyroscope' molecules form crystal that's both solid and full of motion: New type of molecular machine designed by UCLA researchers could have wide-ranging applications in technology and science January 16th, 2018

The nanoscopic structure that locks up our genes January 16th, 2018

Announcements

Scientists synthesize nanoparticle-antioxidants to treat strokes and spinal cord injuries January 16th, 2018

New catalyst for hydrogen production is a step toward clean fuel: Carbon-based nanocomposite with embedded metal ions yields impressive performance as catalyst for electrolysis of water to generate hydrogen January 16th, 2018

'Gyroscope' molecules form crystal that's both solid and full of motion: New type of molecular machine designed by UCLA researchers could have wide-ranging applications in technology and science January 16th, 2018

The nanoscopic structure that locks up our genes January 16th, 2018

Energy

New catalyst for hydrogen production is a step toward clean fuel: Carbon-based nanocomposite with embedded metal ions yields impressive performance as catalyst for electrolysis of water to generate hydrogen January 16th, 2018

Rice U.'s one-step catalyst turns nitrates into water and air: NSF-funded NEWT Center aims for catalytic converter for nitrate-polluted water January 5th, 2018

Tweaking quantum dots powers-up double-pane solar windows: Engineered quantum dots could bring down the cost of solar electricity January 2nd, 2018

Paving the way for a non-electric battery to store solar energy: UMass Amherst scientists say a polymer chain organized like a string of Christmas lights assists energy storage December 22nd, 2017

Fuel Cells

Study boosts hope for cheaper fuel cells: Rice University researchers show how to optimize nanomaterials for fuel-cell cathodes January 6th, 2018

Hydrogen power moves a step closer: Physicists are developing methods of creating renewable fuel from water using quantum technology September 15th, 2017

More durable, less expensive fuel cells: University of Delaware researchers have developed a new technology that could speed up the commercialization of fuel cell vehicles September 5th, 2017

Engineers pioneer platinum shell formation process – and achieve first-ever observation August 11th, 2017

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