Thermoelectric Figure of Merit of Some Compositions in the System (GeTe)1−x[(Ag2Te)1−y(Sb2Te3)y]x

Abstract

Basic thermoelectric p‐type materials for the medium temperature range (600 to 900 K) are GeTe‐based materials. Hot‐pressed samples of (GeTe)1−x[(Ag2Te)1‐y(Sb2Te3)y]x solid solutions with y = 0.6, y = 0.75 are prepared. Their thermoelectric properties (thermoelectric power S, electric conductivity σ and thermal conductivity K) in the temperature range 300 to 750 K are measured. The thermoelectric figure of merit Z = S2σ/K for some compositions in calculated. The best p‐type new material is the composition (GeTe)0.8[(Ag2Te)0.4(Sb2Te3)0.6]0.2 with Zmax = 2.4 × 10−3 K−1 at about 700 K.

Electron Microscopy for Characterization of Thermoelectric Nanomaterials

“…GPA analysis (Fig. 10.21b) confirms the presence of regularly distributed misfit dislocations with the Burger vector 1/2a [101], with $4 nm spacing, at or close to the PbTe/PbS interface. The interfacial contrast is unclear due to the large delocalization of the JEOL-2100F TEM.…”

“…The ZT of TAGS-85 and TAGS-80 alloys can reach 1.4 [100] and 1.9 [101], respectively, at 800 K. Note that the LAST compounds are n-type, while most TAGS alloys are p-type; thus we can use them as the n-and p-type legs in a high-efficiency TE device. The most important characteristic contributing to the high TE performance of TAGS-x is its exceptionally low k lat .…”

Alte und neue Konzepte für thermoelektrische Materialien

“…Für die Zusammensetzung TAGS-80 wurden ZT-Werte bis 1.7 angegeben. [200] [201] Das LAST-m-System ist ein interessantes Bulkmaterial, in dem sich beim Abkühlen der Schmelze spontan Nanostrukturen bilden. Spätere Berichte über das n-System AgPb m SbTe 2+m bestätigten die hohe Gütezahl und die Nanoeinschlüsse.…”

Microstructure and Crystal Structure in TAGS Compositions

“…The dimensionless figure of merit, ZT, for TAGS-85 reaches a maximum of 1.4 at $750 K. 1 The TAGS-80 composition has larger ZT, 1.5 at 750 K, but an associated mechanical instability has eliminated the material from commercial use. 1 Christakudis et al 2 have reported a TAGS-80 ZT as high as 1.7.…”