Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Giving platinum catalysts a golden boost for fuel cells

29.03.2007
Platinum might outweigh gold in the jewelry market, but as part of an ongoing effort to produce efficient and affordable fuel cells, scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory are studying how gold atoms might enhance the value of the pricier metal.

Specifically, they're looking for ways to use gold to prevent the destruction of platinum in the chemical reactions that take place in fuel cells. Brookhaven chemist Radoslav Adzic will describe this research during the 233rd National Meeting of the American Chemical Society at 2 p.m. Central Time (3 p.m. Eastern Time) on Tuesday, March 27, 2007, in room S405A, Level 4, at McCormick Place South, Chicago, Illinois.

Platinum is the most efficient electrocatalyst for accelerating chemical reactions in fuel cells. However, in reactions during the stop-and-go driving of a fuel-cell-powered electric car, the platinum dissolves. In accelerated tests, as much as 45 percent of the catalyst can be lost during five days. "Platinum is by far the best single component catalyst for the oxygen reduction reaction, and we have to find a way to protect it," Adzic said. Under lab conditions that imitate the environment of a fuel cell, Adzic and a team of Brookhaven researchers, including Junliang Zhang, Kotaro Sasaki, and Eli Sutter, added gold clusters to a platinum electrocatalyst, which kept it intact during an accelerated stability test that simulates stop-and-go driving in an electric car.

The details: A fuel cell converts hydrogen and oxygen into water and, as part of the process, produces electricity. Hydrogen is oxidized at the device's anode (the terminal where current flows in) when electrons are released and hydrogen ions are formed; the released electrons supply current for an electric motor. These electrons flow to the cathode (the terminal where current flows out) to reduce oxygen, and in a reaction with hydrogen ions, water, the only byproduct of a fuel cell reaction, is produced. Platinum electrocatalysts are used to speed up the oxidation and reduction reactions involved in this process, but as a result, they, too, are oxidized (lose electrons) and dissolve.

In the unique method used at Brookhaven, researchers place gold on carbon-supported platinum nanoparticles by displacing a single layer of copper and subject it to several sweeps of voltage. The copper is needed to reduce the charged gold particles to neutral atoms; it then conveniently forms a monolayer of platinum by an adsorption process, the binding of molecules or particles to a surface. Using x-rays as probes at Brookhaven's National Synchrotron Light Source, a scanning transmission microscope at Brookhaven's Center for Functional Nanomaterials, and electrochemical techniques in the laboratory, the scientists can show that less platinum is oxidized with this method. As predicted, during laboratory testing, the platinum electrocatalyst remains stable when under conditions mimicking stop-and-go driving conditions. Next, researchers will test the catalyst in real fuel cells at the DOE's Los Alamos National Laboratory in New Mexico.

"The very promising properties of fuel cells have been known for many decades," Adzic said. "But it's only now that we can look at the activities and qualities of the catalysts and find something stable enough to be used in cars or residential applications."

Karen McNulty Walsh | EurekAlert!
Further information:
http://www.bnl.gov

Further reports about: Adzic Brookhaven Fuel Platinum catalyst electrocatalyst

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>