Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Hybrid copper-gold nanoparticles convert CO2--May reduce greenhouse gas emissions

Researchers have combined gold nanoparticles (in light red) with copper nanoparticles (in light green) to form hybrid nanoparticles (dark red), which they turned into powder (foreground) to catalyze carbon dioxide reduction.
Researchers have combined gold nanoparticles (in light red) with copper nanoparticles (in light green) to form hybrid nanoparticles (dark red), which they turned into powder (foreground) to catalyze carbon dioxide reduction.

Abstract:
Copper the stuff of pennies and tea kettles is also one of the few metals that can turn carbon dioxide into hydrocarbon fuels with relatively little energy. When fashioned into an electrode and stimulated with voltage, copper acts as a strong catalyst, setting off an electrochemical reaction with carbon dioxide that reduces the greenhouse gas to methane or methanol.

Hybrid copper-gold nanoparticles convert CO2--May reduce greenhouse gas emissions

Cambridge, MA | Posted on April 11th, 2012

Various researchers around the world have studied copper's potential as an energy-efficient means of recycling carbon dioxide emissions in powerplants: Instead of being released into the atmosphere, carbon dioxide would be circulated through a copper catalyst and turned into methane which could then power the rest of the plant. Such a self-energizing system could vastly reduce greenhouse gas emissions from coal-fired and natural-gas-powered plants.

But copper is temperamental: easily oxidized, as when an old penny turns green. As a result, the metal is unstable, which can significantly slow its reaction with carbon dioxide and produce unwanted byproducts such as carbon monoxide and formic acid.

Now researchers at MIT have come up with a solution that may further reduce the energy needed for copper to convert carbon dioxide, while also making the metal much more stable. The group has engineered tiny nanoparticles of copper mixed with gold, which is resistant to corrosion and oxidation. The researchers observed that just a touch of gold makes copper much more stable. In experiments, they coated electrodes with the hybrid nanoparticles and found that much less energy was needed for these engineered nanoparticles to react with carbon dioxide, compared to nanoparticles of pure copper.

A paper detailing the results will appear in the journal Chemical Communications; the research was funded by the National Science Foundation. Co-author Kimberly Hamad-Schifferli of MIT says the findings point to a potentially energy-efficient means of reducing carbon dioxide emissions from powerplants.

"You normally have to put a lot of energy into converting carbon dioxide into something useful," says Hamad-Schifferli, an associate professor of mechanical engineering and biological engineering. "We demonstrated hybrid copper-gold nanoparticles are much more stable, and have the potential to lower the energy you need for the reaction."

Going small

The team chose to engineer particles at the nanoscale in order to "get more bang for their buck," Hamad-Schifferli says: The smaller the particles, the larger the surface area available for interaction with carbon dioxide molecules. "You could have more sites for the CO2 to come and stick down and get turned into something else," she says.

Hamad-Schifferli worked with Yang Shao-Horn, the Gail E. Kendall Associate Professor of Mechanical Engineering at MIT, postdoc Zichuan Xu and Erica Lai '14. The team settled on gold as a suitable metal to combine with copper mainly because of its known properties. (Researchers have previously combined gold and copper at much larger scales, noting that the combination prevented copper from oxidizing.)

To make the nanoparticles, Hamad-Schifferli and her colleagues mixed salts containing gold into a solution of copper salts. They heated the solution, creating nanoparticles that fused copper with gold. Xu then put the nanoparticles through a series of reactions, turning the solution into a powder that was used to coat a small electrode.

To test the nanoparticles' reactivity, Xu placed the electrode in a beaker of solution and bubbled carbon dioxide into it. He applied a small voltage to the electrode, and measured the resulting current in the solution. The team reasoned that the resulting current would indicate how efficiently the nanoparticles were reacting with the gas: If CO2 molecules were reacting with sites on the electrode and then releasing to allow other CO2 molecules to react with the same sites the current would appear as a certain potential was reached, indicating regular "turnover." If the molecules monopolized sites on the electrode, the reaction would slow down, delaying the appearance of the current at the same potential.

The team ultimately found that the potential applied to reach a steady current was much smaller for hybrid copper-gold nanoparticles than for pure copper and gold an indication that the amount of energy required to run the reaction was much lower than that required when using nanoparticles made of pure copper.

Going forward, Hamad-Schifferli says she hopes to look more closely at the structure of the gold-copper nanoparticles to find an optimal configuration for converting carbon dioxide. So far, the team has demonstrated the effectiveness of nanoparticles composed of one-third gold and two-thirds copper, as well as two-thirds gold and one-third copper.

Hamad-Schifferli acknowledges that coating industrial-scale electrodes partly with gold can get expensive. However, she says, the energy savings and the reuse potential for such electrodes may balance the initial costs.

"It's a tradeoff," Hamad-Schifferli says. "Gold is obviously more expensive than copper. But if it helps you get a product that's more attractive like methane instead of carbon dioxide, and at a lower energy consumption, then it may be worth it. If you could reuse it over and over again, and the durability is higher because of the gold, that's a check in the plus column."

####

For more information, please click here

Contacts:
Caroline McCall
MIT News Office

T: 617-253-1682

Contact:
Sarah McDonnell
MIT News Office

T: 617-253-8923

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

Materials for the next generation of electronics and photovoltaics: MacArthur Fellow develops new uses for carbon nanotubes October 21st, 2014

Special UO microscope captures defects in nanotubes: University of Oregon chemists provide a detailed view of traps that disrupt energy flow, possibly pointing toward improved charge-carrying devices October 21st, 2014

Super stable garnet ceramics may be ideal for high-energy lithium batteries October 21st, 2014

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Detecting Cancer Earlier is Goal of Rutgers-Developed Medical Imaging Technology: Rare earth nanocrystals and infrared light can reveal small cancerous tumors and cardiovascular lesions October 21st, 2014

Chemistry

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Non-Toxic Nanocatalysts Open New Window for Significant Decrease in Reaction Process October 19th, 2014

Discoveries

Special UO microscope captures defects in nanotubes: University of Oregon chemists provide a detailed view of traps that disrupt energy flow, possibly pointing toward improved charge-carrying devices October 21st, 2014

Super stable garnet ceramics may be ideal for high-energy lithium batteries October 21st, 2014

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Detecting Cancer Earlier is Goal of Rutgers-Developed Medical Imaging Technology: Rare earth nanocrystals and infrared light can reveal small cancerous tumors and cardiovascular lesions October 21st, 2014

Announcements

Special UO microscope captures defects in nanotubes: University of Oregon chemists provide a detailed view of traps that disrupt energy flow, possibly pointing toward improved charge-carrying devices October 21st, 2014

Super stable garnet ceramics may be ideal for high-energy lithium batteries October 21st, 2014

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Detecting Cancer Earlier is Goal of Rutgers-Developed Medical Imaging Technology: Rare earth nanocrystals and infrared light can reveal small cancerous tumors and cardiovascular lesions October 21st, 2014

Environment

Imaging electric charge propagating along microbial nanowires October 20th, 2014

Physicists build reversible laser tractor beam October 20th, 2014

Plastic nanoparticles also harm freshwater organisms October 18th, 2014

New Nanocomposites Help Elimination of Toxic Dyes October 15th, 2014

Energy

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

First Canada Excellence Research Chair gets $10 million from the federal government for oilsands research at the University of Calgary: Federal government announces prestigious research chair to study improving oil production efficiency October 19th, 2014

Magnetic mirrors enable new technologies by reflecting light in uncanny ways October 16th, 2014

Unique catalysts for hydrogen fuel cells synthesized in ordinary kitchen microwave oven October 14th, 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 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE