Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

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

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

Imaging

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

Tiny camera lens may help link quantum computers to network September 14th, 2018

Carbon nanodots do an ultrafine job with in vitro lung tissue: New experiments highlight the role of charge and size when it comes to carbon nanodots that mimic the effect of nanoscale pollution particles on the human lung. September 12th, 2018

Chemistry

Halas wins American Chemical Society Award in Colloid Chemistry: Rice University nanophotonics pioneer honored for colloid research September 18th, 2018

How a tetrahedral substance can be more symmetrical than a spherical atom: A new type of symmetry September 14th, 2018

Laboratories

Cannibalistic materials feed on themselves to grow new nanostructures September 1st, 2018

A Novel Graphene Quantum Dot Structure Takes the Cake August 24th, 2018

Virginia Tech researchers develop novel process to 3D print one of the strongest materials on Earth August 23rd, 2018

Connecting the (Nano) Dots: NIST Says Big-Picture Thinking Can Advance Nanoparticle Manufacturing August 22nd, 2018

Govt.-Legislation/Regulation/Funding/Policy

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Researchers develop microbubble scrubber to destroy dangerous biofilms September 19th, 2018

Researchers managed to prevent the disappearing of quantum information September 14th, 2018

New photonic chip promises more robust quantum computers September 14th, 2018

Discoveries

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

NUS researchers invent new test kit for quick, accurate and low-cost screening of diseases: Test results are denoted by a color change and could be further analyzed by a smartphone app, making it attractive as a point-of-care diagnostic device September 19th, 2018

Announcements

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

Tools

Carbon nanodots do an ultrafine job with in vitro lung tissue: New experiments highlight the role of charge and size when it comes to carbon nanodots that mimic the effect of nanoscale pollution particles on the human lung. September 12th, 2018

Terahertz spectroscopy enters the single-molecule regime September 7th, 2018

Mirrorcle Demonstrates MEMS-based Programmable Light Source at CES and PW18 August 30th, 2018

Stress-free ALD from Picosun August 28th, 2018

Energy

Leti Announces EU Project to Develop Powerful, Inexpensive Sensors with Photonic Integrated Circuits: REDFINCH Members Initially Targeting Applications for Gas Detection and Analysis For Refineries & Petrochemical Industry and Protein Analysis for Dairy Industry September 19th, 2018

S, N co-doped carbon nanotube-encapsulated CoS2@Co: Efficient and stable catalysts for water splitting September 10th, 2018

September 5th, 2018

Rice U. lab probes molecular limit of plasmonics: Optical effect detailed in organic molecules with fewer than 50 atoms September 5th, 2018

Fuel Cells

Harvesting clean hydrogen fuel through artificial photosynthesis May 3rd, 2018

A new way to find better battery materials: Design principles could point to better electrolytes for next-generation lithium batteries March 29th, 2018

Rice sleuths find metal in 'metal-free' catalysts: Study of graphene catalysts finds trace of manganese, suggests better ultrathin fuel-cell components February 26th, 2018

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

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project