Navigation Links
New fuel cell catalyst uses 2 metals

Material scientists at Washington University in St. Louis have developed a technique for a bimetallic fuel cell catalyst that is efficient, robust and two to five times more effective than commercial catalysts. The novel technique eventually will enable a cost effective fuel cell technology, which has been waiting in the wings for decades, and should give a boost for cleaner use of fuels worldwide.

Younan Xia, Ph.D., the James M. McKelvey Professor of Biomedical Engineering at Washington University led a team of scientists at Washington University and the Brookhaven National Laboratory in developing a bimetallic catalyst comprised of a palladium core or "seed" that supports dendritic platinum branches, or arms, that are fixed on the nanostructure, consisting of a nine nanometer core and seven nanometer platinum arms. They synthesized the catalysts by sequentially reducing precursor compounds to palladium and platinum with L-ascorbic acid (that is, Vitamin C) in an aqueous solution. The catalysts have a high surface area, invaluable for a number of applications besides in fuel cells, and are robust and stable.

Xia and his team tested how the catalysts performed in the oxygen reduction reaction process in a fuel cell, which determines how large a current will be generated in an electrochemical system similar to the cathode of a fuel cell. They found that their bimetallic nanodendrites, at room temperature, were two-and-a-half times more effective per platinum mass for this process than the state-of-the-art commercial platinum catalyst and five times more active than the other popular commercial catalyst. At 60 C(the typical operation temperature of a fuel cell), the performance almost meets the targets set by the U.S. Department of Energy.

The Department of Energy has estimated for widespread commercial success the "loading" of platinum catalysts in a fuel cell should be reduced by four times in order to slash the costs. The Washington University technique is expected to substantially reduce the loading of platinum, making a more robust catalyst that won't have to be replaced often, and making better use of a very limited and very expensive supply of platinum in the world.

The study was published in Science on-line on May 14.

"There are two ways to make a more effective catalyst," Xia says. "One is to control the size, making it smaller, which gives the catalyst a higher specific surface area on a mass basis. Another is to change the arrangement of atoms on the surface. We did both. You can have a square or hexagonal arrangement for the surface atoms. We chose the hexagonal lattice because people have found that it's twice as good as the square one for the oxygen reduction reaction.

"We're excited by the technique, specifically with the performance of the new catalyst."

Xia says seeded growth has emerged recently as a good technique for precisely controlling the shape and composition of metallic nanostructures prepared in solutions. And it's the only technique that allowed Xia and his collaborators to come up with their unconventional shape.

"When you have something this small, the atoms tend to aggregate and that can reduce the surface area,' Xia says. "A key reason our technique works is the ability to keep the platinum arms fixed. They don't move around. This adds to their stability. We also make sure of the arrangement of atoms on each arm, so we increase the activity."

Xia and his collaborators are exploring the possibility of adding other noble metals such as gold to the bimetallic catalysts, making them trimetallic. Gold has been shown to oxidize carbon monoxide, making for even more robust catalysts that can resist the poisoning by carbon monoxide a reduction byproduct of some fuels.

"Gold should make the catalysts more stable, durable and robust, giving yet another level of control," Xia says.


Contact: Younan Xia
Washington University in St. Louis

Related biology technology :

1. Fate Therapeutics and Stemgent Launch Catalyst: A Unique Industry Program for First Access to the Most Advanced Induced Pluripotent Stem Cell Technology
2. Catalyst Pharmaceutical Partners Reports Fourth Quarter and Year-End 2008 Financial Results
3. Researchers create catalysts for use in hydrogen storage materials
4. Catalyst Biosciences Expands Scientific Advisory Board With Leading Experts in Protease Therapeutic Discovery and Development
5. Brown chemists create more efficient palladium fuel cell catalysts
6. New catalyst paves the path for ethanol-powered fuel cells
7. Coalition for the Advancement of Medical Research Releases New White Paper, Catalyst for Cures: Embryonic Stem Cell Research
8. Eurotech Catalyst Module Awarded to Allen Organ Company From Arrow Electronics
9. PointCross Releases Catalyst for Building Business-Ready SharePoint Solutions in 1/10th the Time
10. Catalyst Pharmaceutical Partners to Present at the Rodman & Renshaw 10th Annual Global Investment Conference
11. Catalyst Pharmaceutical Partners, Inc. Announces a $4.5 Million Registered Direct Common Stock Offering
Post Your Comments:
(Date:10/12/2015)... 12, 2015  Rebiotix Inc. today announced that ... its lead Microbiota Restoration Therapy (MRT) RBX2660 as ... Clostridium difficile (C diff) infection, a ... 29,000 deaths in the U.S. annually. 1 ... was founded to revolutionize the treatment of debilitating ...
(Date:10/12/2015)... 2015 /PRNewswire/ - Aeterna Zentaris Inc. (NASDAQ:  AEZS) (TSX: ... developing and commercializing novel treatments in oncology, endocrinology and ... Turpin , the Company,s former Senior Vice President, Chief ... Quebec City office.  ... Officer of the Company commented, "After a comprehensive review, ...
(Date:10/12/2015)... 12, 2015 ... for enriched online experience --> ... print version for enriched online experience --> ... media alternative to print version for enriched online experience ... scientific, technical and medical information products and services, announced ...
(Date:10/12/2015)... ... October 12, 2015 , ... NeuMedics Inc., is a specialty biopharmaceutical company focused ... safely and chronically be administered as an eye drop, announced today it has been ... Clinic and taking place October 25th to October 28th at The Cleveland Clinic, Cleveland, ...
Breaking Biology Technology:
(Date:9/28/2015)... , Sept. 28, 2015 ... today that its expedited traveler service is ... platform transforms travel, bringing a frictionless experience, ... members. "CLEAR offers our travelers ... customer service," said Jim Smith , ...
(Date:9/26/2015)... , Sept. 26th, 2015  Results of a ... be unveiled today at the Stanford Medicine X ... Using iPad Dashboards, Connected Health Devices and Pharmacogenomics", ... Pharmacy 3.0, will explain how senior patients equipped ... to their pharmacist via the TactioRPM remote patient ...
(Date:9/10/2015)... Sept. 10, 2015 Report Details ... quite delivered upon previous expectations of revenues, consumer adoption ... breakthrough year in which wearables begin to achieve that ... of the main reasons is the entrance of Apple ... the SmartWatches market, but the overall size of the ...
Breaking Biology News(10 mins):