Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New insight into thermoelectric materials may boost green technologies

15.05.2014

A University of Miami physicist and his collaborators find remarkable thermoelectric properties for a metal that may impact the search for materials useful in power generation, refrigeration or energy detection

Thermoelectric materials can turn a temperature difference into an electric voltage. Among their uses in a variety of specialized applications: generating power on space probes and cooling seats in fancy cars.


Lithium purple-bronze (LiPB) is a thermoelectric material comprised of aligned conducting, zig-zag chains of molybdenum and oxygen (left image, pink and white circles with green bonds). When an electric current was applied in a direction slightly misaligned with the chains (depicted as gray lines, right image), heat flowed perpendicular to the current, a phenomenon known as the transverse Peltier effect. The efficiency of this effect in LiPB was among the largest known for a single compound.

Credit: Dr. Joshua Cohn, University of Miami

University of Miami (UM) physicist Joshua Cohn and his collaborators report new surprising properties of a metal named lithium purple-bronze (LiPB) that may impact the search for materials useful in power generation, refrigeration, or energy detection. The findings are published in the journal Physical Review Letters.

"If current efficiencies of thermoelectric materials were doubled, thermoelectric coolers might replace the conventional gas refrigerators in your home," said Cohn, professor and chairman of the UM Department of Physics in the College of Arts and Sciences and lead author of the study. "Converting waste heat into electric power, for example, using vehicle exhaust, is a near-term 'green' application of such materials."

Useful thermoelectric materials produce a large voltage for a given temperature difference, with the ratio known as "thermopower." LiPB is comprised of aligned conducting chains. The researchers found that this material has very different thermopowers when the temperature difference is applied parallel or perpendicular to the conducting chains.

When an electric current was applied in a direction slightly misaligned with the chains, heat flowed perpendicular to the current, a phenomenon known as the "transverse Peltier effect." The efficiency of this effect in LiPB was among the largest known for a single compound.

"That such a large directional difference in thermopower exists in a single compound is exceedingly rare and makes applications possible," Cohn said. "This is significant because transverse Peltier devices typically employ a sandwich of different compounds that is more complicated and costly to fabricate."

As their motivation for the work, Cohn noted that metals with a similar electronic structure often exhibit interesting physics and the thermoelectric properties of LiPB had never been studied in detail. "The present material," he said, "might be useful as it is, but the larger implication of our work is that the ingredients underlying its special properties may serve as a guide to finding or engineering new and improved materials."

###

The study is titled "Extreme Thermopower Anisotropy and Interchain Transport in the Quasi-One-Dimensional Metal Li0.9Mo6O17" Other authors of the study are Saeed Moshfeghyeganeh,Ph.D. student in the Department of Physics at UM; Carlos A. M. dos Santos, professor at the Escola de Engenharia de Lorena in Brazil and John J. Neumeier, professor in the Department of Physics, Montana State University.

Annette Gallagher | Eurek Alert!
Further information:
http://www.miami.edu/

More articles from Materials Sciences:

nachricht New design improves performance of flexible wearable electronics
23.06.2017 | North Carolina State University

nachricht Plant inspiration could lead to flexible electronics
22.06.2017 | American Chemical Society

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>