View : 54 Download: 0

Band Degeneracy, Low Thermal Conductivity, and High Thermoelectric Figure of Merit in SnTe-CaTe Alloys

Title
Band Degeneracy, Low Thermal Conductivity, and High Thermoelectric Figure of Merit in SnTe-CaTe Alloys
Authors
Al Orabi, Rabih Al RahalMechosky, Nicolas A.Hwang, JunphilKim, WoochulRhyee, Jong-SooWee, DaehyunFornari, Marco
Ewha Authors
위대현
SCOPUS Author ID
위대현scopus
Issue Date
2016
Journal Title
CHEMISTRY OF MATERIALS
ISSN
0897-4756JCR Link1520-5002JCR Link
Citation
vol. 28, no. 1, pp. 376 - 384
Publisher
AMER CHEMICAL SOC
Indexed
SCI; SCIE; SCOPUS WOS scopus
Abstract
Pure lead-free SnTe has limited thermoelectric potentials because of the low Seebeck coefficients and the relatively large thermal conductivity. In this study, we provide experimental evidence and theoretical understanding that alloying SnTe with Ca greatly improves the transport properties leading to ZT of 1.35 at 873 K, the highest ZT value so far reported for singly doped SnTe materials. The introduction of Ca (0-9%) in SnTe induces multiple effects: (1) Ca replaces Sn and reduces the hole concentration due to Sn vacancies, (2) the energy gap increases, limiting the bipolar transport, (3) several bands with larger effective masses become active in transport, and (4) the lattice thermal conductivity is reduced by about 70% due to the contribution of concomitant scattering terms associated with the alloy disorder and the presence of nanoscale precipitates. An efficiency of similar to 10% (for Delta T = 400 K) was predicted for high-temperature thermoelectric power generation using SnTe-based p- and n-type materials.
DOI
10.1021/acs.chemmater.5b04365
Appears in Collections:
엘텍공과대학 > 환경공학전공 > Journal papers
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE