Rare earth chalcogenide Ce3Te4 as high efficiency high temperature thermoelectric material

Abstract

The electronic band structures of Ce 3 Te 4 have been studied using the first-principles density-functional theory calculations. It is found that the density of states of Ce 3 Te 4 has a very high delta-shaped peak appearing 0.21 eV above the Fermi level, which mainly comes from the f orbital electrons of the rare-earth element Ce. Using the simple theory proposed by Mahan and Sofo, ͓Proc. Natl. Acad. Sci. U.S.A. 93, 7436 ͑1996͔͒, we obtain an ideal value of zT= 13.5 for Ce 3 Te 4 at T = 1200 K, suggesting that the rare-earth chalcogenide Ce 3 Te 4 could be a promising high efficiency high temperature thermoelectric material.

Two-dimensional boron monochalcogenide monolayer for thermoelectric material

“…[9][10][11][12][13] There are various crystal structures of different materials that provide good thermoelectric performance, such as Half-Heusler compounds, 14 clathrates, 15 skutterudites, 16 perovskites, 17 antiperovskite, 18 some oxide materials 19,20 and chalcogenides. 21,22 The elements of group 16 (O, S, Se, Te) are known as chalcogens. Materials that contain at least one chalcogen atom are known as chalcogenide materials.…”

Optimal Bandwidth for High Efficiency Thermoelectrics

“…The original theoretical work by Mahan and Sofo [9] showed that an electronic structure with a delta-shaped transport distribution function (TDF) leads to a maximum ZT. Many of the band structure engineering works for TE materials over the past decade have somewhat followed this guideline by introducing a sharp density of states (DOS) [10,11,12,13,14], including the search for rare-earth compounds and transition-metal compounds [15,16,17], introducing impurity levels in bulk semiconductor materials [18], and the nanostructured materials with low-dimensional miniband formation [1,19].…”

Thermoelectric Properties of Ce₃Te₄ under High Pressure: First-Principles Calculation

“…In addition, it would also be noticed that the height and width of DOS peak also change with pressure. According to the Mahan-Sofo s analytic model about thermoelectric materials 16,18) , the electrical conductivity, thermopower, and electronic thermal conductivity are related to the common transport distribution function s(x), where x is the dimensionless electron energy scaled by k B T and measured from Fermi level, and the ZT value is optimized when the DOS peak locates at x 0 ±2.4 k B T above the Fermi level. If the thermoelectric material is operated at T = 1200 K, the optimal DOS peak would locate at 0.25 eV.…”

“…Recently, Andrew F. May synthesized lanthanum telluride (La 3 Te 4 ) in the experiment and found that its ZT value reaches 1.1 at 1275 K 15) . In addition, the thermoelectric properties of cerium telluride (Ce 3 Te 4 ) crystal under 0 GPa pressure with high temperature have also been calculated, whose ZT value is 13.5 at T = 1200 K 16) , which is higher than that of La 3 Te 4 , although Andrew F. May found that the thermoelectric transport properties in Ce 3 Te 4 are similar to those of La 3 Te 4 below room temperature 17) . This shows that the Ce 3 Te 4 crystal is currently the very ef cient high tem-perature thermoelectric material.…”