Bismuth Telluride and Its Alloys as Materials for Thermoelectric Generation

Abstract

Bismuth telluride and its alloys are widely used as materials for thermoelectric refrigeration. They are also the best materials for use in thermoelectric generators when the temperature of the heat source is moderate. The dimensionless figure of merit, ZT, usually rises with temperature, as long as there is only one type of charge carrier. Eventually, though, minority carrier conduction becomes significant and ZT decreases above a certain temperature. There is also the possibility of chemical decomposition due to the vaporization of tellurium. Here we discuss the likely temperature dependence of the thermoelectric parameters and the means by which the composition may be optimized for applications above room temperature. The results of these theoretical predictions are compared with the observed properties of bismuth telluride-based thermoelements at elevated temperatures. Compositional changes are suggested for materials that are destined for generator modules.

Self‐Tuning n‐Type Bi2(Te,Se)3/SiC Thermoelectric Nanocomposites to Realize High Performances up to 300 °C

“…As the state‐of‐the‐art thermoelectric material, Bi 2 Te 3 ‐based ingots show high zT at room temperature (RT) and have been employed in industry for decades in solid‐state cooling 13. Recently, the applications of Bi 2 Te 3 ‐based thermoelectric materials in waste‐heat recovery in the low‐mid temperature range are receiving more and more attention 14.…”

A novel route to nanostructured bismuth telluride films by electrodeposition

“…The currently best performing TE materials in commercial TE devices are based on bulk Bi 2 Te 3 used for refrigeration and waste heat recovery up to 200 °C [2]. Theoretical calculations by Dresselhaus et al [3,4] predict that low dimensional structures such as 1D nanowires or 2D quantum wells systems could dramatically enhance the thermoelectric performance of materials due to quantum confinement effects and enhanced phonon scattering at heterointerfaces that leads to a reduction in the thermal conductivity.…”

Thermoelectric performance enhancement in n-type Bi2(TeSe)3 alloys owing to nanoscale inhomogeneity combined with a spark plasma-textured microstructure

“…5,6 A great variety of thermoelectric materials have been developed and thoroughly studied, [7][8][9] but industrial applications are still dominated by bismuth telluride (Bi 2 Te 3 )-based alloys. 10 Therefore, extensive studies have been devoted to the enhancement of their properties. Industrially used ingots of Bi 2 Te 3 -based alloys are fabricated using a zone melting process, which is capable of enhancing the preferential crystal growth and chemical purity.…”