Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

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

New method allows for greater variation in band gap tunability: The method can change a material's electronic band gap by up to 200 percent January 31st, 2015

Evidence mounts for quantum criticality theory: Findings bolster theory that quantum fluctuations drive strange electronic phenomena January 30th, 2015

Everything You Need To Know About Nanopesticides January 30th, 2015

DNA nanoswitches reveal how life's molecules connect: An accessible new way to study molecular interactions could lower cost and time associated with discovering new drugs January 30th, 2015

Imaging

Park Systems Announces Innovations in Bio Cell Analysis with the Launch of Park NX-Bio, the only 3-in-1 Imaging Nanoscale Tool Available for Life Science Researchers January 29th, 2015

2015 Nanonics Image Contest January 29th, 2015

JPK opens new expanded offices in Berlin to meet the growing demand for products worldwide January 28th, 2015

Pittcon News: Renishaw adds to the comprehensive imaging options available with its inVia confocal Raman microscope January 27th, 2015

Discoveries

New method allows for greater variation in band gap tunability: The method can change a material's electronic band gap by up to 200 percent January 31st, 2015

Evidence mounts for quantum criticality theory: Findings bolster theory that quantum fluctuations drive strange electronic phenomena January 30th, 2015

Everything You Need To Know About Nanopesticides January 30th, 2015

DNA nanoswitches reveal how life's molecules connect: An accessible new way to study molecular interactions could lower cost and time associated with discovering new drugs January 30th, 2015

Announcements

New method allows for greater variation in band gap tunability: The method can change a material's electronic band gap by up to 200 percent January 31st, 2015

Evidence mounts for quantum criticality theory: Findings bolster theory that quantum fluctuations drive strange electronic phenomena January 30th, 2015

Everything You Need To Know About Nanopesticides January 30th, 2015

DNA nanoswitches reveal how life's molecules connect: An accessible new way to study molecular interactions could lower cost and time associated with discovering new drugs January 30th, 2015

Energy

New method allows for greater variation in band gap tunability: The method can change a material's electronic band gap by up to 200 percent January 31st, 2015

Crystal light: New light-converting materials point to cheaper, more efficient solar power: University of Toronto engineers study first single crystal perovskites for new solar cell and LED applications January 30th, 2015

Los Alamos Develops New Technique for Growing High-Efficiency Perovskite Solar Cells: Researchersí crystal-production insights resolve manufacturing difficulty January 29th, 2015

Carbon nanoballs can greatly contribute to sustainable energy supply January 27th, 2015

Fuel Cells

New concept of fuel cell for efficiency and environment: It grasps both performance efficiency and removal of toxic heavy metal ions in direct methanol fuel cells January 5th, 2015

Toward a low-cost 'artificial leaf' that produces clean hydrogen fuel December 3rd, 2014

Single-atom gold catalysts may offer path to low-cost production of fuel and chemicals November 28th, 2014

National Synchrotron Light Source II Achieves 'First Light' October 23rd, 2014

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







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE