Navigation Links
Nanotech milling produces dramatic increase in thermoelectric performance of bulk semiconductor
Date:1/25/2011

CHESTNUT HILL, MA (1/25/11) -- Researchers from Boston College, MIT, Clemson and Virginia have used nanotechnology to achieve a 60-90 percent increase in the thermoelectric figure of merit of p-type half-Heusler, a common bulk semiconductor compound, the team reported in the American Chemical Society journal Nano Letters.

The dramatic increase in the figure of merit, used to measure a material's relative thermoelectric performance, could pave the way for a new generation of products from car exhaust systems and power plants to solar power technology that that runs cleaner, according to co-author Yan Xiao, a researcher in the Department of Physics at Boston College.

The team registered improvement in half-Heusler, which has been under study for its thermal stability, mechanical sturdiness, non-toxicity and low cost. However, the application of half-Heusler has been limited because of its poor thermoelectric performance: it previously registered a peak figure of merit of approximately 0.5 at 700 degrees Celsius for bulk ingots.

Xiao, working with BC Professor of Physics Zhifeng Ren and MIT's Soderberg Professor of Power Engineering Gang Chen, said the team produced an increase in the figure of merit value of p-type half-Heusler to 0.8 at 700 degrees Celsius. Moreover, the groups' material preparation methods proved to save time and expense compared with conventional methods.

"This method is low cost and can be scaled for mass production," Ren said. "This represents an exciting opportunity to improve the performance of thermoelectric materials in a cost-effective manner."

The researchers obtained their results by first forming alloyed ingots using arc melting technique and then creating nanoscale powders by ball milling the ingots and finally obtaining dense bulk by hot pressing. Transport property measurements together with microstructure studies on the nanostructured samples, in comparison with that of bulk ingots, showed that the thermoelectric performance improves largely because of low thermal conductivity produced by enhanced phonon scattering at grain boundaries and defects in the material. The material was also found to have a high Seebeck coefficient, a measure of thermoelectric power.

Researchers in the BC and MIT labs are still trying to prevent grain growth during press, which accounts for the still large thermal conductivity of half-Heusler.

"Even lower thermal conductivity and improved thermoelectric performance can be expected when average grain sizes are made smaller than 100 nm," said Ren, who was joined on the team by fellow Boston College researchers Giri Joshi, Weishu Liu, Yucheng Lan and Hui Wang, MIT's Sangyeop Lee, Virginia's Rogers Professor of Physics Joe Poons and J.W. Simonson and Clemson Professor of Physics Terry M. Tritt.


'/>"/>

Contact: Ed Hayward
ed.hayward@bc.edu
617-552-4826
Boston College
Source:Eurekalert

Related biology technology :

1. William F. Prendergast Named One of the Top IP Lawyers in Nanotechnology
2. Consumer Product Safety Commission not ready for nanotech
3. New nanotechnology centre helps turn big ideas into real products
4. Nanotechnology and the FDA: size matters
5. Parallel nano-soldering technique chosen for years top-50 by Nanotech Briefs
6. Using living cells as nanotechnology factories
7. The frontiers of nanotechnology
8. Penn State gets $5M NSF grant for Nanotech Applications and Career Knowledge
9. TechConnect World 2009 Matches Tomorrows Technology Solutions with Todays Business Needs for Clean-Technology, Biotechnology and Nanotechnology
10. Aldrich(R) Releases Materials Science Catalog That Includes Products to Advance Sustainable Energy and Nanotechnology Research
11. Sigma-Aldrich Signs Agreement With SouthWest NanoTechnologies to Distribute SWeNT(R) Single-Wall Carbon Nanotubes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/23/2017)... ... 2017 , ... AxioMed president, Jake Lubinski, describes the AxioMed ... deformed, which is identical to how the human discs work to distribute force. ... to its natural state along a hysteresis curve, exactly like a healthy human ...
(Date:3/23/2017)... 2017  Northwest Biotherapeutics (OTCQB: NWBO) (NW Bio), ... for solid tumor cancers, today announced that yesterday ... announced last Friday, March 17, 2017. ... securities totaling 28,843,692 shares, comprised of 18,843,692 common ... of Class C Warrants pre-funded at the closing ...
(Date:3/23/2017)... -- BioPharmX Corporation (NYSE MKT: BPMX), a specialty pharmaceutical ... reported financial results for the quarter and year ... update on the company,s clinical development efforts and ... pleased to report that last year was a ... Krammer. "We achieved key clinical milestones and attracted ...
(Date:3/23/2017)... , March 23, 2017 NetworkNewsWire ... ... death, putting significant strain on health care systems, in terms ... diagnoses rises, so too does the development of innovative and ... side effects. Among the many types of cancer treatments, a ...
Breaking Biology Technology:
(Date:3/9/2017)... MOUNTAIN VIEW, Calif. , March 9, 2017 /PRNewswire/ ... 23andMe , the leading personal genetics company, are ... can now provide customers with personalized nutrition plans that ... biometrics, but also genetic markers impacting how their body ... personalized food decision support platform uses biometrics such as ...
(Date:3/6/2017)... March 6, 2017 Mintigo , ... today announced Predictive Sales Coach TM , its ... sales intelligence into Salesforce. This unique AI application ... sales organizations with deep knowledge of their customers ... intelligent engagement. Predictive Sales Coach extends Mintigo,s existing ...
(Date:3/2/2017)... 2017 Who risk to be deprived of ... full report: https://www.reportbuyer.com/product/4313699/ WILL APPLE AND ... Fingerprint sensors using capacitive technology represent a fast ... Idex forecasts an increase of 360% of the number ... the fingerprint sensor market between 2014 and 2017 (source ...
Breaking Biology News(10 mins):