Featured Research

from universities, journals, and other organizations

Platinum Nanocube Makes Hydrogen Fuel Cells Cheaper And More Efficient

Date:
April 22, 2008
Source:
Brown University
Summary:
Two great obstacles to hydrogen-powered vehicles lie with fuel cells. Fuel cells, which like batteries produce electrical power through chemical reactions, have been plagued by their relatively low efficiency and high production costs. Scientists have tested a wide assortment of metals and materials to overcome the twin challenge.

Making a Platinum Nanocube. Transmission electron microscopy, far left, shows 7-nm. platinum nanocubes used for oxygen reduction reaction. In the upper right corner is a high-resolution picture of a single nanocube. The illustration depicts oxygen reduction on the surface of a nanocube.
Credit: Chao Wang/Brown University

Two great obstacles to hydrogen-powered vehicles lie with fuel cells. Fuel cells, which like batteries produce electrical power through chemical reactions, have been plagued by their relatively low efficiency and high production costs. Scientists have tested a wide assortment of metals and materials to overcome the twin challenge.

Now a team led by Shouheng Sun, professor of chemistry at Brown, has mastered a Rubik’s Cube-like dilemma for dealing with platinum, a precious metal coveted for its ability to boost a chemical reaction in fuel cells. The team shows that shaping platinum into a cube greatly enhances its efficiency in a phase of the fuel cell’s operation known as oxygen reduction reaction. Sun’s results have been published online in the journal Angewandte Chemie. The paper was selected as a Very Important Paper, a distinction reserved for less than 5 percent of manuscripts submitted to the peer-reviewed journal.

Platinum helps reduce the energy barrier – the amount of energy needed to start a reaction – in the oxidation phase of a fuel cell. It is also seen as beneficial on the other end of the fuel cell, known as the cathode. There, platinum has been shown to assist in oxygen reduction, a process in which electrons peeled from hydrogen atoms join with oxygen atoms to create electrical energy. The reaction also is important because it only produces water. This byproduct – rather than the global warming gas carbon dioxide – is a big reason why hydrogen fuel cells are a tantalizing area of research from automakers in Detroit to policy-makers in Washington.

Scientists, however, have had trouble maximizing platinum’s potential in the oxygen reduction reaction. The barriers chiefly revolve around shape and surface area – geometry and geography, so to speak. What Sun has learned is that molding platinum into a cube on the nanoscale enhances its catalysis – that is, it boosts the rate of a chemical reaction.

“For the first time, we can control the morphology of the particle to make it more like a cube,” Sun said. “People have had very limited control over this process before. Now we have shown it can be done uniformly and consistently.”

During his experiments, Sun, along with Brown graduate engineering student Chao Wang and engineers from the Japanese firm Hitachi Maxwell Ltd., created polyhedron and cube shapes of different sizes by adding platinum acetylacetonate (Pt(acac)2) and a trace amount of iron pentacarbonyl (Fe(CO)5) at specific temperature ranges. The team found that cubes were more efficient catalysts, owing largely to their surface structure and their resistance to being absorbed by the sulfate in the fuel cell solution.

“For this reaction, the shape is more important than the size,” Sun said.

The next step, Sun added, is to build a polymer electrolyte membrane fuel cell and test the platinum nanocubes as catalysts in it. The team expects the experiments will yield fuel cells with a higher electrical output than previous versions.

“It’s like science fiction, but we’re a step closer now to the reality of developing a very efficient platinum catalyst for hydrogen cars that produce only water as exhaust,” Sun said.

Hitachi Maxell chemical engineers Hideo Daimon, Taigo Ondera and Tetsunori Koda, a visiting engineer at Brown, contributed to the research.

The research was funded by the National Science Foundation and by the Office of the Vice President for Research at Brown University through its Research Seed Fund.


Story Source:

The above story is based on materials provided by Brown University. Note: Materials may be edited for content and length.


Cite This Page:

Brown University. "Platinum Nanocube Makes Hydrogen Fuel Cells Cheaper And More Efficient." ScienceDaily. ScienceDaily, 22 April 2008. <www.sciencedaily.com/releases/2008/04/080418090427.htm>.
Brown University. (2008, April 22). Platinum Nanocube Makes Hydrogen Fuel Cells Cheaper And More Efficient. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2008/04/080418090427.htm
Brown University. "Platinum Nanocube Makes Hydrogen Fuel Cells Cheaper And More Efficient." ScienceDaily. www.sciencedaily.com/releases/2008/04/080418090427.htm (accessed July 31, 2014).

Share This




More Matter & Energy News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
7 Ways to Use Toothpaste: Howdini Hacks

7 Ways to Use Toothpaste: Howdini Hacks

Howdini (July 30, 2014) Fresh breath and clean teeth are great, but have you ever thought, "my toothpaste could be doing more". Well, it can! Lots of things! Howdini has 7 new uses for this household staple. Video provided by Howdini
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
Smartphone Powered Paper Plane Debuts at Airshow

Smartphone Powered Paper Plane Debuts at Airshow

AP (July 30, 2014) Smartphone powered paper airplane that was popular on crowdfunding website KickStarter makes its debut at Wisconsin airshow (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins