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Title: The Thermoelectric Properties of Bismuth Telluride
Abstract

Bismuth telluride is the working material for most Peltier cooling devices and thermoelectric generators. This is because Bi2Te3(or more precisely its alloys with Sb2Te3for p‐type and Bi2Se3for n‐type material) has the highest thermoelectric figure of merit,zT, of any material around room temperature. Since thermoelectric technology will be greatly enhanced by improving Bi2Te3or finding a superior material, this review aims to identify and quantify the key material properties that make Bi2Te3such a good thermoelectric. The largezTcan be traced to the high band degeneracy, low effective mass, high carrier mobility, and relatively low lattice thermal conductivity, which all contribute to its remarkably high thermoelectric quality factor. Using literature data augmented with newer results, these material parameters are quantified, giving clear insight into the tailoring of the electronic band structure of Bi2Te3by alloying, or reducing thermal conductivity by nanostructuring. For example, this analysis clearly shows that the minority carrier excitation across the small bandgap significantly limits the thermoelectric performance of Bi2Te3, even at room temperature, showing that larger bandgap alloys are needed for higher temperature operation. Such effective material parameters can also be used for benchmarking future improvements in Bi2Te3or new replacement materials.

 
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Award ID(s):
1729594 1729487
NSF-PAR ID:
10461107
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Electronic Materials
Volume:
5
Issue:
6
ISSN:
2199-160X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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