Improved thermoelectric efficiency in p-type ZnSb through Zn deficiency

2015 ◽  
Vol 08 (02) ◽  
pp. 1550028 ◽  
Author(s):  
Qilong Guo ◽  
Sijun Luo
Keyword(s):  
Figure Of Merit ◽  
Lattice Thermal Conductivity ◽  
Hole Concentration ◽  
Zn Deficiency ◽  
Thermoelectric Efficiency ◽  
Thermoelectric Figure ◽  
Pristine Sample ◽  
Zn Content ◽  
P Type ◽  
Content Regulation

We herein report a feasible approach to improve the thermoelectric performance of p-type ZnSb compound by Zn content regulation. It is found that Zn vacancies formed by Zn deficiency not only efficiently enhance the electrical conductivity due to the improved hole concentration but also markedly lower the lattice thermal conductivity on account of the reinforced point defect scattering of phonons. The ZnSb compound with a nominal 3 mol.% Zn deficiency shows a maximum thermoelectric figure of merit ZT of ~ 0.8 at 700 K which is a ~ 60% improvement over the pristine sample. The strategies of further enhancing the performance of ZnSb -based material have been discussed.

Effects of Ce filling fraction and Fe content on the thermoelectric properties of Co-rich CeyFexCo4−xSb12

2001 ◽  
Vol 16 (3) ◽  
pp. 837-843 ◽  
Author(s):  
Xinfeng Tang ◽  
Lidong Chen ◽  
Takashi Goto ◽  
Toshio Hirai
Keyword(s):  
Thermal Conductivity ◽  
Thermoelectric Properties ◽  
Figure Of Merit ◽  
Single Phase ◽  
Lattice Thermal Conductivity ◽  
Hole Concentration ◽  
Thermoelectric Figure Of Merit ◽  
Thermoelectric Figure ◽  
Filling Fraction ◽  
Fe Content

Single-phase filled skutterudite compounds, CeyFexCo4−xSb12 (x = 0 to 3.0, y = 0 to 0.74), were synthesized by a melting method. The effects of Fe content and Ce filling fraction on the thermoelectric properties of CeyFexCo4−xSb12 were investigated. The lattice thermal conductivity of Ce-saturated CeyFexCo4−xSb12, y being at the maximum corresponding to x, decreased with increasing Fe content (x) and reached its minimum at about x = 1.5. When x was 1.5, lattice thermal conductivity decreased with increasing Ce filling fraction till y = 0.3 and then began to increase after reaching the minimum at y = 0.3. Hole concentration and electrical conductivity of Cey Fe1.5Co2.5Sb12 decreased with increasing Ce filling fraction. The Seebeck coefficient increased with increasing Ce filling fraction. The greatest dimensionless thermoelectric figure of merit T value of 1.1 was obtained at 750 K for the composition of Ce0.28Fe1.52Co2.48Sb12.

scholarly journals Термоэлектрические свойства нанокомпозитного Bi-=SUB=-0.45-=/SUB=-Sb-=SUB=-1.55-=/SUB=-Te-=SUB=-2.985-=/SUB=- с микрочастицами SiO-=SUB=-2-=/SUB=-

2019 ◽  
Vol 53 (6) ◽  
pp. 751
Author(s):  
А.А. Шабалдин ◽  
П.П. Константинов ◽  
Д.А. Курдюков ◽  
Л.Н. Лукьянова ◽  
А.Ю. Самунин ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Solid Solution ◽  
Electrical Conductivity ◽  
Wide Temperature Range ◽  
Figure Of Merit ◽  
Nanostructured Material ◽  
Thermoelectric Figure Of Merit ◽  
Thermoelectric Efficiency ◽  
Thermoelectric Figure ◽  
P Type

AbstractNanocomposite thermoelectrics based on Bi_0.45Sb_1.55Te_2.985 solid solution of p -type conductivity are fabricated by the hot pressing of nanopowders of this solid solution with the addition of SiO_2 microparticles. Investigations of the thermoelectric properties show that the thermoelectric power of the nanocomposites increases in a wide temperature range of 80–420 K, while the thermal conductivity considerably decreases at 80–320 K, which, despite a decrease in the electrical conductivity, leads to an increase in the thermoelectric efficiency in the nanostructured material without the SiO_2 addition by almost 50% (at 300 K). When adding SiO_2, the efficiency decreases. The initial thermoelectric fabricated without nanostructuring, in which the maximal thermoelectric figure of merit ZT = 1 at 390 K, is most efficient at temperatures above 350 K.

Thermal Conductivity of Zn4−xCdxSb3 Solid Solutions

1997 ◽  
Vol 478 ◽  
Author(s):  
T. Caillat ◽  
A. Borshchevsky ◽  
J. -P. Fleurial
Keyword(s):  
Thermal Conductivity ◽  
High Performance ◽  
Figure Of Merit ◽  
Lattice Thermal Conductivity ◽  
State Of The Art ◽  
Thermoelectric Figure Of Merit ◽  
Thermoelectric Figure ◽  
Jet Propulsion ◽  
P Type ◽  
Electrical Conductors

Abstractβ-Zn4Sb3 was recently identified at the Jet Propulsion Laboratory as a new high performance p-type thermoelectric material with a maximum dimensionless thermoelectric figure of merit ZT of 1.4 at a temperature of 673K. A usual approach, used for many state-of-the-art thermoelectric materials, to further improve ZT values is to alloy β-Zn4Sb3 with isostructural compounds because of the expected decrease in lattice thermal conductivity. We have grown Zn4−xCdxSb3 crystals with 0.2≤x<1.2 and measured their thermal conductivity from 10 to 500K. The thermal conductivity values of Zn4−xCdxSb3 alloys are significantly lower than those measured for β-Zn4Sb3 and are comparable to its calculated minimum thermal conductivity. A strong atomic disorder is believed to be primarily at the origin of the very low thermal conductivity of these materials which are also fairly good electrical conductors and are therefore excellent candidates for thermoelectric applications.

Thermoelectric performance of MoSi(2)As(4) monolayer

2022 ◽  
Author(s):  
Yuhong Huang ◽  
Xuanhong Zhong ◽  
Hongkuan Yuan ◽  
Hong Chen
Keyword(s):  
Figure Of Merit ◽  
Density Functional ◽  
Lattice Thermal Conductivity ◽  
Thermoelectric Performance ◽  
Potential Candidate ◽  
Boltzmann Transport ◽  
Maximal Power ◽  
Thermoelectric Figure ◽  
Functional Theory ◽  
P Type

Abstract Thermoelectric performance of MoSi2As4 monolayer is investigated using density functional theory combined with Boltzmann transport theoy. The maximal power factors of n- and p-type by PBE (HSE06) functional are 7.73 (48.31) and 32.84 (30.50) mW m-1 K-2 at the temperature of 1200 K, respectively. The lattice thermal conductivity is less than 30 W m-1 K-1 above 800 K. The thermoelectric figure of merit can reach 0.33 (0.58) and 0.90 (0.81) using PBE (HSE06) functional for n- and p-type under appropriate carrier concentration at 1200K, respectively. Thus, the p-type MoSi2As4 monolayer is predicted to be a potential candidate for high-temperature thermoelectric applications.

THERMOELECTRIC PROPERTIES OF Bi2Te3–Sb2Te3 ALLOYS

1965 ◽  
Vol 43 (4) ◽  
pp. 653-669 ◽  
Author(s):  
C. H. Champness ◽  
P. T. Chiang ◽  
P. Parekh
Keyword(s):  
Entire Range ◽  
Figure Of Merit ◽  
Hole Concentration ◽  
Zone Melting ◽  
Nominal Composition ◽  
Thermoelectric Figure Of Merit ◽  
Thermoelectric Figure ◽  
Antimony Content ◽  
Melting Method ◽  
P Type

Alloys of nominal composition Bi2−xSbxTe3+y were prepared in an evacuated, sealed ampule by a horizontal zone melting method. Single-crystal samples were cut from the ingots, and measurements of Seebeck coefficient, electrical conductivity, thermoelectric figure of merit (Z), and thermal conductivity (κ) were made over a temperature range of 160 to 360 °K using the Peltier–Seebeck method developed by Harman. Alloys of nominal composition Bi2−xSbxTe3.13 were found to be n type for [Formula: see text] and p type for x > 1. In alloys of high antimony content, the hole concentration was influenced very little by the amount of excess tellurium. The change of Z was studied by varying y from 0.06 to 0.26 at x equal to 0, 0.25, 1.4, 1.5, and 1.6 respectively. Optimum doping to maximize Z did not appear to be possible in a simple way over the entire range of x between 0 and 2. The temperature dependence of κ indicated that the maximum Z at x = 1.5 may be limited by an ambipolar contribution.

Nanocomposite of Bi2Te3 with Metal Inclusions for Advanced Thermoelectric Applications

2009 ◽  
Vol 1218 ◽  
Author(s):  
Sumithra Santhanam ◽  
Nathan J. Takas ◽  
Dinesh Misra ◽  
Pierre F. P. Poudeu ◽  
Kevin L. Stokes
Keyword(s):  
Thermal Conductivity ◽  
Figure Of Merit ◽  
Lattice Thermal Conductivity ◽  
Electrical Power ◽  
Nanometer Scale ◽  
Thermoelectric Figure Of Merit ◽  
Thermoelectric Efficiency ◽  
Thermoelectric Figure ◽  
Thermal And Electrical Properties ◽  
Experimental And Theoretical Studies

AbstractRecent experimental and theoretical studies have shown that the thermal to electrical power conversion efficiency (as measured by the thermoelectric figure of merit) can be enhanced in nanocomposite materials. Primarily, these efforts to improve the thermoelectric efficiency rely on reducing the lattice thermal conductivity through nanostructuring of the materials or the introduction of a second nanometer-scale phase into the composite material. Here, we show that the inclusion of semimetal nanoparticles into bismuth telluride (Bi2Te3) can result in both an increase in the electronic transport properties (so called "power factor") as well as a decrease in lattice thermal conductivity. The effect of different volume fractions of Bi nanoinclusions (3% and 5%) on the thermal and electrical properties of the composite are reported. A marginal increase in the thermoelectric figure of merit is achieved for 3% metal nanoinclusion, whereas a significant improvement in the figure of merit could be achieved for 5% nanoinclusions in the Bi2Te3 thermoelectric matrix.

Advances in thermoelectric (GeTe) x (AgSbTe2)100-x

2021 ◽  
Author(s):  
Hongxia Liu ◽  
Xinyue Zhang ◽  
Wen Li ◽  
Yanzhong Pei
Keyword(s):  
Band Structure ◽  
Figure Of Merit ◽  
Lattice Thermal Conductivity ◽  
Thermoelectric Generators ◽  
Thermoelectric Figure ◽  
Promising Candidate ◽  
Thermoelectric Transport Properties ◽  
Electronic Performance ◽  
P Type ◽  
Strong Anharmonicity

Abstract The (GeTe) x (AgSbTe2)100-x alloys, also called TAGS-x in short, have long been demonstrated as a promising candidate for thermoelectric applications with successful services as the p-type leg in radioisotope thermoelectric generators for space missions. This largely stems from the complex band structure for a superior electronic performance and strong anharmonicity for a low lattice thermal conductivity. Utilization of the proven strategies including carrier concentration optimization, band and defects engineering, an extraordinary thermoelectric figure of merit, zT, has been achieved in TAGS-based alloys. Here, crystal structure, band structure, microstructure, synthesis techniques and thermoelectric transport properties of TAGS-based alloys, as well as successful strategies for manipulating the thermoelectric performance, are surveyed with opportunities for further advancements. These strategies involved are believed to be in principle applicable for advancing many other thermoelectrics.

scholarly journals Влияние термической предыстории на свойства эффективных термоэлектрических сплавов Ge-=SUB=-0.86-=/SUB=-Pb-=SUB=-0.1-=/SUB=-Bi-=SUB=-0.04-=/SUB=-Te-=SUP=-*-=/SUP=-

2022 ◽  
Vol 56 (3) ◽  
pp. 261
Author(s):  
А.А. Шабалдин ◽  
А.Ю. Самунин ◽  
П.П. Константинов ◽  
С.В. Новиков ◽  
А.Т. Бурков ◽  
...  
Keyword(s):  
Figure Of Merit ◽  
Structural Modification ◽  
Lattice Thermal Conductivity ◽  
Partial Substitution ◽  
Thermoelectric Efficiency ◽  
Thermoelectric Figure ◽  
Maximum Value ◽  
History Of ◽  
Simultaneous Decrease ◽  
Good Agreement

In this work, we study the properties of GeTe -based alloys, doped with bismuth, with partial substitution of lead for germanium: Ge0.86Pb0.1Bi0.04Te. The aim of the study is to explore the possibility of increasing the thermoelectric efficiency of a compound by combining optimal doping and isovalent substitution to improve the electronic properties with a simultaneous decrease of the lattice thermal conductivity. We studied alloy samples prepared in two different research laboratories using similar, but not completely identical procedures. It is shown that the electronic (thermoelectric power and electrical conductivity) properties of the samples of the two groups are in good agreement with each other. The properties of alloys depend on the thermal history of the samples due to the presence at temperatures of 600–800 K of a phase transition from a low-temperature rhombohedral to a high-temperature cubic structural modification. The thermoelectric figure of merit of alloys reaches a maximum value of 1.5 at a temperature of about 750 K.

OXYCHALCOGENIDES AS NEW EFFICIENT p-TYPE THERMOELECTRIC MATERIALS

2013 ◽  
Vol 06 (05) ◽  
pp. 1340007 ◽  
Author(s):  
CELINE BARRETEAU ◽  
LIN PAN ◽  
YAN-LING PEI ◽  
LI-DONG ZHAO ◽  
DAVID BERARDAN ◽  
...  
Keyword(s):  
Figure Of Merit ◽  
Parent Compound ◽  
Thermoelectric Figure ◽  
Medium Temperature ◽  
Temperature Range ◽  
The Past ◽  
Thermoelectric Conversion ◽  
New Directions ◽  
Wide Scale ◽  
P Type

During the past two years, we have underlined the great potential of p-type oxychalcogenides, with parent compound BiCuSeO , for thermoelectric applications in the medium temperature range (400–650°C). These materials, which do not contain lead and are less expensive than Te containing materials, exhibit large thermoelectric figure of merit, exceeding 1 in a wide temperature range, mainly due to an intrinsically very low thermal conductivity. This paper summarizes the main chemical and crystallographic features of this system, as well as the thermoelectric properties. It also gives new directions to improve these properties, and discuss the potential of these materials for wide scale applications in thermoelectric conversion system in the medium temperature range.

High-Thermoelectric Figure of Merit Realized in p-Type Half-Heusler Compounds: ZrCoSnxSb1-x

2007 ◽  
Vol 46 (No. 27) ◽  
pp. L673-L675 ◽  
Author(s):  
Takeyuki Sekimoto ◽  
Ken Kurosaki ◽  
Hiroaki Muta ◽  
Shinsuke Yamanaka
Keyword(s):  
Figure Of Merit ◽  
Thermoelectric Figure Of Merit ◽  
Heusler Compounds ◽  
Thermoelectric Figure ◽  
P Type
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