skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Nanoscale clusters in the high performance thermoelectric AgPb{sub m}SbTe{sub m+2}

Abstract

The local structure of the AgPb{sub m}SbTe{sub m+2} series of thermoelectric materials has been studied using the atomic pair distribution function (PDF) method. Three candidate-models were attempted for the structure of this class of materials using either a one- or a two-phase modeling procedure. Combining modeling the PDF with HRTEM data we show that AgPb{sub m}SbTe{sub m+2} contains nanoscale inclusions with composition close to AgPb{sub 3}SbTe{sub 5} randomly embedded in a PbTe matrix.

Authors:
; ; ; ;  [1];  [2]
  1. Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20719779
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 72; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevB.72.174113; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIMONY COMPOUNDS; CRYSTAL STRUCTURE; DISTRIBUTION FUNCTIONS; INCLUSIONS; LEAD TELLURIDES; NANOSTRUCTURES; PERFORMANCE; SILVER COMPOUNDS; SIMULATION; THERMOELECTRIC MATERIALS; THERMOELECTRICITY; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Lin, H., Bozin, E.S., Billinge, S.J.L., Quarez, Eric, Kanatzidis, M.G., and Department of Chemistry, Michigan State University, East Lansing, Michigan 48824. Nanoscale clusters in the high performance thermoelectric AgPb{sub m}SbTe{sub m+2}. United States: N. p., 2005. Web. doi:10.1103/PhysRevB.72.174113.
Lin, H., Bozin, E.S., Billinge, S.J.L., Quarez, Eric, Kanatzidis, M.G., & Department of Chemistry, Michigan State University, East Lansing, Michigan 48824. Nanoscale clusters in the high performance thermoelectric AgPb{sub m}SbTe{sub m+2}. United States. doi:10.1103/PhysRevB.72.174113.
Lin, H., Bozin, E.S., Billinge, S.J.L., Quarez, Eric, Kanatzidis, M.G., and Department of Chemistry, Michigan State University, East Lansing, Michigan 48824. Tue . "Nanoscale clusters in the high performance thermoelectric AgPb{sub m}SbTe{sub m+2}". United States. doi:10.1103/PhysRevB.72.174113.
@article{osti_20719779,
title = {Nanoscale clusters in the high performance thermoelectric AgPb{sub m}SbTe{sub m+2}},
author = {Lin, H. and Bozin, E.S. and Billinge, S.J.L. and Quarez, Eric and Kanatzidis, M.G. and Department of Chemistry, Michigan State University, East Lansing, Michigan 48824},
abstractNote = {The local structure of the AgPb{sub m}SbTe{sub m+2} series of thermoelectric materials has been studied using the atomic pair distribution function (PDF) method. Three candidate-models were attempted for the structure of this class of materials using either a one- or a two-phase modeling procedure. Combining modeling the PDF with HRTEM data we show that AgPb{sub m}SbTe{sub m+2} contains nanoscale inclusions with composition close to AgPb{sub 3}SbTe{sub 5} randomly embedded in a PbTe matrix.},
doi = {10.1103/PhysRevB.72.174113},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 17,
volume = 72,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
  • No abstract prepared.
  • The nanostructuring occurring in the AgPb{sub 18}SbTe{sub 20} system is documented and it is shown to contain coherent or semi-coherent Ag-rich nano-inclusions, most in range of 2 to 30 nm embedded in an essentially PbTe matrix. The analysis of the nanostructuring supports the mechanism believed to be responsible for achieving a high thermoelectric figure-of-merit.
  • We demonstrate that the KPb{sub m}SbTe{sub 2+m} system (PLAT-m for tellurium, antimony, lead potassium, m = 19-21) of materials exhibits high thermoelectric performance. Samples with compositions K{sub 1-x}Pb{sub m+{delta}}Sb{sub 1+{gamma}}Te{sub m+2} were prepared using several combinations of x, {delta}, {gamma} and m and their thermoelectric properties were investigated in the temperature range of 300-800 K. All K{sub 1-x}Pb{sub m+{delta}}Sb{sub 1+{gamma}}Te{sub m+2} samples exhibited n-type conduction over the measured temperature range. Their lattice thermal conductivities were found to be significantly reduced when compared to PbTe and even AgPb{sub m}SbTe{sub m+2}. For example, for K{sub 0.95}Pb{sub 20}Sb{sub 1.2}Te{sub 22} a lattice thermalmore » conductivity as low as 0.4 W/(m {center_dot} K) was estimated at 650 K (based on a Lorenz number of 1.25 x 10{sup -8} W {center_dot} {Omega}/K{sup 2}). High resolution transmission electron microscopy on several samples revealed a widely dispersed nanoscale particle with varying size and shape endotaxially embedded inside a PbTe-rich matrix which is believed to be responsible for the reduced lattice thermal conductivity of K{sub 1-x}Pb{sub m+{delta}}Sb{sub 1+{gamma}}Te{sub m+2} materials. Because of their small size, the nanoinclusions are coherent with the matrix and therefore do not markedly degrade the electrical conductivity of the materials. As a result, very high figures of merit are achieved at high temperature for several compositions. For K{sub 0.95}Pb{sub 20}Sb{sub 1.2}Te{sub 22}, a maximum figure of merit ZT {approx} 1.6 was obtained around 750 K. This value is similar to that of n-type LAST-18 and is two times larger than that of the-state-of-the-art n-type PbTe.« less