Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Touch of gold improves nanoparticle fuel-cell reactions

Midas touch on the nanoscale Gold atoms create orderly places for iron and platinum atoms, then retreat to the periphery of the fuel cell, where they scrub carbon monoxide from fuel reactions. The tighter organization and cleaner reactions extend the cell's performance life. Credit: Sun Lab/Brown University
Midas touch on the nanoscale Gold atoms create orderly places for iron and platinum atoms, then retreat to the periphery of the fuel cell, where they scrub carbon monoxide from fuel reactions. The tighter organization and cleaner reactions extend the cell's performance life.

Credit: Sun Lab/Brown University

Abstract:
Chemists at Brown University have created a triple-headed metallic nanoparticle that reportedly performs better and lasts longer than any other nanoparticle catalyst studied in fuel-cell reactions. The key is the addition of gold: It yields a more uniform crystal structure while removing carbon monoxide from the reaction. Results published in the Journal of the American Chemical Society.

Touch of gold improves nanoparticle fuel-cell reactions

Providence, RI | Posted on March 12th, 2012

Advances in fuel-cell technology have been stymied by the inadequacy of metals studied as catalysts. The drawback to platinum, other than cost, is that it absorbs carbon monoxide in reactions involving fuel cells powered by organic materials like formic acid. A more recently tested metal, palladium, breaks down over time.

Now chemists at Brown University have created a triple-headed metallic nanoparticle that they say outperforms and outlasts all others at the anode end in formic-acid fuel-cell reactions. In a paper published in the Journal of the American Chemical Society, the researchers report a 4-nanometer iron-platinum-gold nanoparticle (FePtAu), with a tetragonal crystal structure, generates higher current per unit of mass than any other nanoparticle catalyst tested. Moreover, the trimetallic nanoparticle at Brown performs nearly as well after 13 hours as it did at the start. By contrast, another nanoparticle assembly tested under identical conditions lost nearly 90 percent of its performance in just one-quarter of the time.

"We've developed a formic acid fuel-cell catalyst that is the best to have been created and tested so far," said Shouheng Sun, chemistry professor at Brown and corresponding author on the paper. "It has good durability as well as good activity."

Gold plays key roles in the reaction. First, it acts as a community organizer of sorts, leading the iron and platinum atoms into neat, uniform layers within the nanoparticle. The gold atoms then exit the stage, binding to the outer surface of the nanoparticle assembly. Gold is effective at ordering the iron and platinum atoms because the gold atoms create extra space within the nanoparticle sphere at the outset. When the gold atoms diffuse from the space upon heating, they create more room for the iron and platinum atoms to assemble themselves. Gold creates the crystallization chemists want in the nanoparticle assembly at lower temperature.

Gold also removes carbon monoxide (CO) from the reaction by catalyzing its oxidation. Carbon monoxide, other than being dangerous to breathe, binds well to iron and platinum atoms, gumming up the reaction. By essentially scrubbing it from the reaction, gold improves the performance of the iron-platinum catalyst. The team decided to try gold after reading in the literature that gold nanoparticles were effective at oxidizing carbon monoxide so effective, in fact, that gold nanoparticles had been incorporated into the helmets of Japanese firefighters. Indeed, the Brown team's triple-headed metallic nanoparticles worked just as well at removing CO in the oxidation of formic acid, although it is unclear specifically why.

The authors also highlight the importance of creating an ordered crystal structure for the nanoparticle catalyst. Gold helps researchers get a crystal structure called "face-centered-tetragonal," a four-sided shape in which iron and platinum atoms essentially are forced to occupy specific positions in the structure, creating more order. By imposing atomic order, the iron and platinum layers bind more tightly in the structure, thus making the assembly more stable and durable, essential to better-performing and longer-lasting catalysts.

In experiments, the FePtAu catalyst reached 2809.9 mA/mg Pt (mass-activity, or current generated per milligram of platinum), "which is the highest among all NP (nanoparticle) catalysts ever reported," the Brown researchers write. After 13 hours, the FePtAu nanoparticle has a mass activity of 2600mA/mg Pt, or 93 percent of its original performance value. In comparison, the scientists write, the well-received platinum-bismuth nanoparticle has a mass activity of about 1720mA/mg Pt under identical experiments, and is four times less active when measured for durability.

The researchers note that other metals may be substituted for gold in the nanoparticle catalyst to improve the catalyst's performance and durability.

"This communication presents a new structure-control strategy to tune and optimize nanoparticle catalysis for fuel oxidations," the researchers write.

Sen Zhang, a third-year graduate student in Sun's lab, helped with the nanoparticle design and synthesis. Shaojun Guo, a postdoctoral fellow in Sun's lab performed electrochemical oxidation experiments. Huiyuan Zhu, a second-year graduate student in Sun's lab, synthesized the FePt nanoparticles and ran control experiments. The other contributing author is Dong Su from the Center for Functional Nanomaterials at Brookhaven National Laboratory, who analyzed the structure of the nanoparticle catalyst using the advanced electron microscopy facilities there.

The U.S. Department of Energy and the Exxon Mobil Corporation funded the research.

####

For more information, please click here

Contacts:
Richard Lewis
401-863-3766

Copyright © Brown University

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

Why Is Google Making Synthetic Arms? February 1st, 2015

Nanomaterials Used to Reduce Heat Generated by LED Panels February 1st, 2015

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

Performance Drop in Solar Cells Prevented by Nanotechnology February 1st, 2015

Chemistry

Creating new materials with quantum effects for electronics January 29th, 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

Laboratories

Nanoscale Mirrored Cavities Amplify, Connect Quantum Memories: Advance could lead to quantum computing and the secure transfer of information over long-distance fiber optic networks January 28th, 2015

New pathway to valleytronics January 27th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

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

Nanoscale Mirrored Cavities Amplify, Connect Quantum Memories: Advance could lead to quantum computing and the secure transfer of information over long-distance fiber optic networks January 28th, 2015

Detecting chemical weapons with a color-changing film January 28th, 2015

Discoveries

Nanomaterials Used to Reduce Heat Generated by LED Panels February 1st, 2015

Performance Drop in Solar Cells Prevented by Nanotechnology February 1st, 2015

Pinholes are Pitfalls for High Performance Solar Cells February 1st, 2015

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

Announcements

Why Is Google Making Synthetic Arms? February 1st, 2015

Nanomaterials Used to Reduce Heat Generated by LED Panels February 1st, 2015

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

Performance Drop in Solar Cells Prevented by Nanotechnology February 1st, 2015

Tools

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

Hiden Gas Analysers at PITTCON 2015 | Visit us on Booth No. 1127 January 29th, 2015

Advantest to Exhibit at SEMICON Korea in Seoul, South Korea February 4-6 Showcasing Broad Portfolio of Semiconductor Products, Technologies and Solutions January 29th, 2015

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

Energy

Performance Drop in Solar Cells Prevented by Nanotechnology February 1st, 2015

Pinholes are Pitfalls for High Performance Solar Cells February 1st, 2015

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

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