by Staff Writers
Blacksburg VA (SPX) Jun 24, 2011
Researchers at Virginia Tech in Blacksburg, Va. recently found a way to improve electricity generating fuel cells, potentially making them more efficient, powerful and less expensive. Specifically, they discovered a way to speed up the flow and filtering of water or ions, which are necessary for fuel cells to operate.
Simply put, the researchers stretched Nafion, a polymer electrolyte membrane, or PEM, commonly used in fuel cells and increased the speed at which it selectively filters substances from ions and water.
The resulting process could be important to a number of energy and environment-related applications such as any of several industrial processes that involve filtering, including improving batteries in cars, water desalination and even the production of artificial muscles for robots.
The journal Nature Materials published the results in its June 19 issue in the article, "Linear coupling of alignment with transport in a polymer electrolyte membrane," by Jing Li, Jong Keun Park, Robert B. Moore and Louis A. Madsen, all with the chemistry department in the College of Science and the Macromolecules and Interfaces Institute at Virginia Tech.
"I got the idea for some of these experiments after I saw Bob Moore give a talk at the University of North Carolina about Nafion when I was a post-doc there working with liquid crystals," said Madsen, an assistant professor of physical, polymer and materials chemistry who led the study.
In order to improve PEMs, Madsen and Virginia Tech Chemistry Professor Robert Moore studied exactly how water moves through Nafion at the molecular level and measured how changes in the structure of the material affected water flow. They found stretching it caused channels in the PEM material to align in the direction of the stretch, allowing water to flow through faster.
"Stretching drastically influences the degree of alignment," said Madsen. "So the molecules move faster along the direction of the stretch, and in a very predictable way. These materials actually share some properties with liquid crystals--molecules that line up with each other and are used in every LCD television, projector and screen."
"This is a very clever approach which demonstrates the advantages of interdisciplinary materials research and which may offer important benefits to both energy technologies and sustainability of our natural resources," said Andy Lovinger, polymers program director in the National Science Foundation's Division of Materials Research, which funded the study.
Nafion was discovered in the 1960's and is made up of molecules that combine the non-stick and tough nature of Teflon with the conductive properties of an acid. It is one of many PEMs used to filter water and ions that the researchers say could benefit from the stretching process.
Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.
Rare earth minerals prices skyrocket
Beijing (UPI) Jun 23, 2011
China has doubled or tripled the prices of some rare earth metals, raising concerns about global supplies of the 17 elements, crucial for green energy and high-tech components. Just in the last three weeks europium oxide, used in the manufacturing of energy-saving light bulbs, plasma TVs and smartphones has nearly tripled in price from about $1,260 a kilogram to $3,400, The Guardian new ... read more
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2011 - Space Media Network. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|