Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Smaller isn't always better: Catalyst simulations could lower fuel cell cost

Schematic of PEMFC platinum nanoparticle catalyst on graphite carbon support
Schematic of PEMFC platinum nanoparticle catalyst on graphite carbon support

Abstract:
Imagine a car that runs on hydrogen from solar power and produces water instead of carbon emissions. While vehicles like this won't be on the market anytime soon, UW-Madison researchers are making incremental but important strides in the fuel cell technology that could make clean cars a reality.

Smaller isn't always better: Catalyst simulations could lower fuel cell cost

Madison, WI | Posted on September 21st, 2009

Materials Science and Engineering Assistant Professor Dane Morgan and PhD student Edward (Ted) Holby have developed a computational model that could optimize an important component of fuel cells, making it possible for the technology to have a more widespread use. Essentially, they investigate how particle size relates to the overall stability of a material, and their model has shown that increasing the particle size of a fuel cell catalyst decreases degradation and therefore increases the useful lifetime of a fuel cell.

Fuel cells are electrochemical devices that facilitate a reaction between hydrogen and oxygen, producing electrical power and forming water. In the type of fuel cells Morgan is researching, called proton exchange membrane fuel cells, or PEMFCs, hydrogen is split into a proton and electron at one side of the fuel cell (the anode). The proton moves through the device while the electron is forced to travel in an external circuit, where it can perform useful work. At the other side of the fuel cell (the cathode), the protons, electrons and oxygen combine to form water, which is the only waste product.

Though the premise sounds straightforward, there are multiple hurdles to producing efficient fuel cells for widespread use. One of these hurdles is the catalyst added to aid the reaction between protons, electrons and oxygen at the cathode. Current fuel cells use platinum and platinum alloys as a catalyst. While platinum can withstand the corrosive fuel cell environment, it is expensive and not very abundant.

To maximize platinum use, researchers use catalysts made with platinum particles as small as 2 nanometers, which are approximately 10 atoms across. These tiny structures have a large surface area on which the fuel cell reaction occurs. However, platinum catalysts this small degrade very quickly.

"The stability of bulk versus nanoparticle materials can be understood intuitively by thinking of cheese," says Morgan. "When you leave a large chunk of cheese out and the edges get crusty the surface is destroyed, but you can cut that off and there is still a lot of cheese inside that is good.

"But if you crumble the cheese into tiny pieces and leave it out, you destroy all of your cheese because a larger fraction of the cheese is at the surface."

Rapid catalyst degradation means the fuel cell doesn't last long, and the U.S. Department of Energy estimates fuel cells must function for 5,000 hours, or approximately seven months of continuous use, to be practical for automotive energy solutions.

Morgan and Holby, who are working in collaboration with Professor Yang Shao-Horn from the Massachusetts Institute of Technology, have found a possible solution to the rapid degradation problem: When it comes to catalyst particle size, sometimes smaller isn't better.

Their modeling work, which is funded by 3M and the U.S. Department of Energy, shows that if the particle size of a platinum catalyst is increased to 4 or 5 nanometers, which is approximately 20 atoms across, the level of degradation significantly decreases. This means the catalyst and the fuel cell as a whole can continue to function for much longer than if the particle size was only 2 or 3 nanometers.

The research into the fundamental physics of particle size will be useful as scientists extend their platinum studies to exploring platinum alloys, which can reduce platinum consumption when used as fuel cell catalysts. Morgan is beginning to research models to study size effects on the stability of platinum alloys, such as copper-platinum and cobalt-platinum catalysts.

"Fuel cells are just one of many energy technologies-solar, battery, etc. — with enormous potential to reduce our dependence on oil and our carbon emissions," says Morgan. "Computer simulation offers a powerful tool to understand and develop new materials at the heart of these energy technologies."

####

About University of Wisconsin-Madison
The University of Wisconsin System is one of the largest systems of public higher education in the country, serving more than 175,000 students each year and employing more than 32,000 faculty and staff statewide.

For more information, please click here

Contacts:
James Beal
608/263-0611

Copyright © University of Wisconsin-Madison

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

Clues to inner atomic life from subtle light-emission shifts: Hyperfine structure of light absorption by short-lived cadmium atom isotopes reveals characteristics of the nucleus that matter for high precision detection methods July 3rd, 2015

Pioneering Southampton scientist awarded prestigious physics medal July 3rd, 2015

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

Discovery of nanotubes offers new clues about cell-to-cell communication July 2nd, 2015

Nanospiked bacteria are the brightest hard X-ray emitters July 2nd, 2015

Chemistry

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Possible Futures

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

Harris & Harris Group Portfolio Company D-Wave Systems Announces 1,000 Qubit Processor and is Discussed in the Economist June 23rd, 2015

Global Nanoclays Market Analysis, Size, Growth, Trends And Segment Forecasts, 2015 To 2022: Grand View Research, Inc June 15th, 2015

Healthcare Nanotechnology (Nanomedicine) Market Size To 2020 June 5th, 2015

Announcements

Clues to inner atomic life from subtle light-emission shifts: Hyperfine structure of light absorption by short-lived cadmium atom isotopes reveals characteristics of the nucleus that matter for high precision detection methods July 3rd, 2015

Pioneering Southampton scientist awarded prestigious physics medal July 3rd, 2015

Groundbreaking research to help control liquids at micro and nano scales July 3rd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 2015

Environment

NIST ‘How-To’ Website Documents Procedures for Nano-EHS Research and Testing July 1st, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

The peaks and valleys of silicon: Team of USC Viterbi School of Engineering Researchers introduce new layered semiconducting materials as silicon alternative June 27th, 2015

NNI Publishes Workshop Report and Launches Web Portal on Nanosensors: Both outputs support the Nanotechnology Signature Initiative ‘Nanotechnology for Sensors and Sensors for Nanotechnology: Improving and Protecting Health, Safety, and the Environment’ June 24th, 2015

Energy

New technology using silver may hold key to electronics advances July 2nd, 2015

Visible Light-Sensitive Photocatalysts Used for Purification of Contaminated Water in Iran June 30th, 2015

June 29th, 2015

Making new materials with micro-explosions: ANU media release: Scientists have made exotic new materials by creating laser-induced micro-explosions in silicon, the common computer chip material June 29th, 2015

Automotive/Transportation

June 29th, 2015

Buckle up for fast ionic conduction June 16th, 2015

A protective shield for sensitive catalysts: Hydrogels block harmful oxygen June 15th, 2015

Slip sliding away: Graphene and diamonds prove a slippery combination June 10th, 2015

Fuel Cells

The Hydrogen-Fuel cell will revolutionize the economy of the world: New non-platinum and nanosized catalyst for polymer electrolyte fuel cell June 29th, 2015

X-rays and electrons join forces to map catalytic reactions in real-time: New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions June 29th, 2015

Buckle up for fast ionic conduction June 16th, 2015

A protective shield for sensitive catalysts: Hydrogels block harmful oxygen June 15th, 2015

Solar/Photovoltaic

Making new materials with micro-explosions: ANU media release: Scientists have made exotic new materials by creating laser-induced micro-explosions in silicon, the common computer chip material June 29th, 2015

Spain nanotechnology featured at NANO KOREA 2015 June 26th, 2015

Stanford researchers stretch a thin crystal to get better solar cells June 25th, 2015

Toward tiny, solar-powered sensors: New ultralow-power circuit improves efficiency of energy harvesting to more than 80 percent June 23rd, 2015

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