CsBi ₄ Te ₆ : A High-Performance Thermoelectric Material for Low-Temperature Applications

Abstract

Thermoelectric (Peltier) heat pumps are capable of refrigerating solid or fluid objects, and unlike conventional vapor compressor systems, they can be miniaturized without loss of efficiency. More efficient thermoelectric materials need to be identified, especially for low-temperature applications in electronics and devices. The material CsBi(4)Te(6) has been synthesized and its properties have been studied. When doped appropriately, it exhibits a high thermoelectric figure of merit below room temperature (ZT(max) approximately 0.8 at 225 kelvin). At cryogenic temperatures, the thermoelectric properties of CsBi(4)Te(6) appear to match or exceed those of Bi(2-x)Sb(x)Te(3-y)Se(y) alloys.

High-performance nanostructured thermoelectric materials

“…A relaxation-time model for electrical carrier-interface scattering was developed to account for the fi ltering eff ect of low-energy electrons on transport properties. Tl x Pb 1-x Te [17] AgSbTe 2 [14] Ag-Pb-Sb-Te (LAST) [15] (GeTe) 1-x (AgSbTe 2 ) x (TAGS) [16] CsBi 4 Te 6 [12] Yb x Co 4 Sb 12 (skutterudites) [18] SiGe [19] Yb x Ba 8-x Ga 16 Ge 30 (clathrates) [25] Hf 0.6 Zr 0.4 NiSn 0.98 Sb 0.02 (half-Heusler) [24] Yb 14 Mn 1-x Al x Sb 11 (Zintl phase) [23] Temperature ( n-type (Mg 2 Si y Ge 1-y )-(Mg 2 Si 0.6 Ge 0.4 ) nanocomposites. Th e inspired work of Kanatzidis's group revealed that a new kind of intrinsic nano-inclusion, as shown schematically in Figure 3(k), formatted by the segregation of silver and antimony in the lead sublattice of PbTe, could achieve simultaneous phonon blocking and electron transmission.…”

MnS Incorporation into Higher Manganese Silicide Yields a Green Thermoelectric Composite with High Performance/Price Ratio

“…The ξ of the  A a B b … N n compound can be calculated using the following formula$\begin{array}{c}\xi \hspace{0.17em}\text{=}\frac{\text{TE}\hspace{0.17em}\text{performance}}{\text{Unit}\hspace{0.17em}\text{price}\hspace{0.17em}\text{of}\hspace{0.17em}\text{compound}}\\ \text{=}\frac{ZT}{{\displaystyle \sum \frac{x{M}_X}{M_{A_a{B}_b\dots N_n}}}\times P_{m,X}}\hspace{0.17em}\\ \text{=}\frac{ZT}{\frac{a{M}_A}{M_{A_a{B}_b\dots N_n}}\times P_{m,\hspace{0.17em}A}+\frac{b{M}_B}{M_{A_a{B}_b\dots N_n}}\times P_{m,\hspace{0.17em}B}+\dots +\frac{n{M}_N}{M_{A_a{B}_b\dots N_n}}\times P_{m,\hspace{0.17em}N}}\end{array}$where X is a certain element of the A a B b … N n compound, M is the mole mass of the selected element of the A a B b … N n compound, and P m is the element price based on unit mass. The most optimal ZT values and corresponding ξ of typical TE materials from low to high temperature are listed in Figure 4D 8, 10, 11, 21, 52, 53, 54, 55. Although ZT of the (HMS) 0.99 (MnS) 0.01 composite was the lowest among the selected TE representatives, its corresponding ξ is higher than those of the most other materials.…”

High thermoelectric performance of oxyselenides: intrinsically low thermal conductivity of Ca-doped BiCuSeO

“…Alternatively, high-performance single-phase thermoelectric materials can be obtained using materials with intrinsically low lattice thermal conductivities. Typical materials included in this class are as follows: AgSbTe 2 (kB0.39 Wm À1 K À1 , ZTB1.6 at 673 K), 10,11 Ag 9 TlTe 5 (kB0.22 Wm À1 K À1 , ZTB1.2 at 700 K), 12 Ag 0.95 GaTe 2 (kB0.20 Wm À1 K À1 , ZTB0.7 at 850 K), 13 Ag 3.9 Mo 9 Se 11 (kB0.75 Wm À1 K À1 , ZTB0.6 at 800 K), 14 Cu 3 SbSe 4 (kB0.50 Wm À1 K À1 , ZTB0.8 at 650 K), 15 Cu 2 Ga 4 Te 7 (kB0.67 Wm À1 K À1 , ZTB0.6 at 940 K), 16 Cu 2.1 Zn 0.9 SnSe 4 (kB0.50 Wm À1 K À1 , ZTB0.9 at 860 K), 17 Cu 2 Ga 0.07 Ge 0.93 Se 3 (kB0.67 Wm À1 K À1 , ZTB0.5 at 745 K), 18 CsBi 4 Te 6 (kB0.50 Wm À1 K À1 , ZTB0.8 at 275 K), 19 and K 2 Bi 8 Se 13 (kB0.80 Wm À1 K À1 , ZTB0.4 at 400 K). 20 Recently, we reported a quaternary BiCuSeO compound that exhibits very low thermal conductivity.…”