Laser synthesis of copper oxides 2D structures with high Seebeck coefficient and high thermoelectric figure of merit

ABSTRACTWe report transport properties of polycrystalline TMGa3(TM = Fe and Ru) compounds in the temperature range 313K<T<973K. These compounds exhibit semiconductorlike behavior with relatively high Seebeck coefficient, electrical resistivity, and Hall carrier concentrations at room temperature in the range of 1017- 1018cm−3. Seebeck coefficient measurements reveal that FeGa3isn-type material, while the Seebeck coefficient of RuGa3changes signs rapidly from large positive values to large negative values around 450K. The thermal conductivity of these compounds is estimated to be 3.5Wm−1K−1at room temperature and decreased to 2.5Wm−1K−1for FeGa3and 2.0Wm−1K−1for RuGa3at high temperature. The resulting thermoelectric figure of merit,ZT, at 945K for RuGa3reaches 0.18.

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N-Type Bismuth Telluride Nanocomposite Materials Optimization for Thermoelectric Generators in Wearable Applications

Materials ◽

10.3390/ma12091529 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1529 ◽

Cited By ~ 13

Author(s):

Amin Nozariasbmarz ◽

Jerzy S. Krasinski ◽

Daryoosh Vashaee

Keyword(s):

Thermal Conductivity ◽

Power Generation ◽

Seebeck Coefficient ◽

Figure Of Merit ◽

Microwave Cavity ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

Efficient Operation ◽

High Seebeck Coefficient ◽

Body Heat

Thermoelectric materials could play a crucial role in the future of wearable electronic devices. They can continuously generate electricity from body heat. For efficient operation in wearable systems, in addition to a high thermoelectric figure of merit, zT, the thermoelectric material must have low thermal conductivity and a high Seebeck coefficient. In this study, we successfully synthesized high-performance nanocomposites of n-type Bi2Te2.7Se0.3, optimized especially for body heat harvesting and power generation applications. Different techniques such as dopant optimization, glass inclusion, microwave radiation in a single mode microwave cavity, and sintering conditions were used to optimize the temperature-dependent thermoelectric properties of Bi2Te2.7Se0.3. The effects of these techniques were studied and compared with each other. A room temperature thermal conductivity as low as 0.65 W/mK and high Seebeck coefficient of −297 μV/K were obtained for a wearable application, while maintaining a high thermoelectric figure of merit, zT, of 0.87 and an average zT of 0.82 over the entire temperature range of 25 °C to 225 °C, which makes the material appropriate for a variety of power generation applications.

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Легирование термоэлектрических материалов на основе твeрдых растворов SiGe в процессе их синтеза методом электроимпульсного плазменного спекания

Физика и техника полупроводников ◽

10.21883/ftp.2019.09.48121.04 ◽

2019 ◽

Vol 53 (9) ◽

pp. 1182

Author(s):

М.В. Дорохин ◽

П.Б. Демина ◽

И.В. Ерофеева ◽

А.В. Здоровейщев ◽

Ю.М. Кузнецов ◽

...

Keyword(s):

Solid Solution ◽

Seebeck Coefficient ◽

Figure Of Merit ◽

Thermoelectric Figure Of Merit ◽

Sintering Process ◽

Thermoelectric Figure ◽

Plasma Sintering ◽

Sb Doping ◽

Spark Plasma ◽

Large Clusters

AbstractThe results of investigation of thermoelectric materials fabricated by spark plasma sintering and based on Si_1 –_ x Ge_ x solid solutions doped with Sb to a concentration of 0–5 at % are presented. It was found that, at Sb concentration below 1 at %, efficient doping of the solid solution was carried out during the sintering process, which allowed us to form a thermoelectric material with a relatively high thermoelectric figure of merit. An increase in the concentration of antimony in the range of 1–5 at % led to a change in the mechanism of doping, which resulted in an increase in the resistance of materials and the segregation of Sb into large clusters. For such materials, a significant decrease in the Seebeck coefficient and thermoelectric figure of merit was noted. The highest obtained thermoelectric figure of merit (ZT) with Sb doping was 0.32 at 350°C, which is comparable with known analogues for the Ge_ x Si_1 –_ x solid solution.

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Enhancement of Thermopower due to Deficiency of Sb in FeSb2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.665.179 ◽

2013 ◽

Vol 665 ◽

pp. 179-181 ◽

Cited By ~ 3

Author(s):

Anup V. Sanchela ◽

Varun Kushwaha ◽

Ajay. D. Thakur ◽

C.V. Tomy

Keyword(s):

Thermal Conductivity ◽

Seebeck Coefficient ◽

Low Temperatures ◽

Figure Of Merit ◽

Room Temperature ◽

Parent Compound ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

Thermoelectric Power Factor ◽

Anomalous Peak

FeSb2 was recently found to be a narrow-gap semiconductor with strong electronelectron correlation and a large thermopower at low temperatures. We report measurements of the electrical resistivity, Seebeck coefficient and thermal conductivity between 5 K to 300 K on polycrystalline samples of FeSb2 and FeSb1.9. We found that the deficiency of Sb in the parent compound leads to a giant anomalous peak in thermopower (S) at low temperatures, reaching ~ 426 μV/K at 20 K, resulting in a high thermoelectric power factor at low temperatures, achieving 10 μW/K2m at 27 K.. Consequently, a significantly enhanced thermoelectric figure of merit ZT ~ 0.0015 is achieved near room temperature. At low temperatures there is no improvement in ZT values due to the high thermal conductivity (phonon dominant region). Keywords: Seebeck coefficient, thermal conductivity, resistivity, thermoelectric figure of merit. PACS: 72.20.Pa, 71.27.+a, 71.28.+d

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Influence of Magnetic Impurities on Thermoelectric Capabilities of Bi2Te3, Sb2Te3, and Bi2Se3

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.190.558 ◽

2012 ◽

Vol 190 ◽

pp. 558-561

Author(s):

V.A. Kulbachinskii ◽

V.G. Kytin ◽

A.A. Kudryashov ◽

P.M. Tarasov

Keyword(s):

Seebeck Coefficient ◽

Figure Of Merit ◽

Hole Concentration ◽

Magnetic Impurities ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

Cr Content ◽

Hall Effects ◽

Fe Content ◽

Cr Doping

Temperature dependencies of the Seebeck coefficient, electrical conductivity, heat conductivity and the dimensionless thermoelectric figure of merit ZT ofp-Bi2Te3,n-Bi2Se3and Sb2Te3doped by Fe or Cr have been investigated in the temperature interval 7 <T< 300 K. At T=4.2 K the Shubnikov-de Haas and Hall effects have been measured.By increasing the Fe content, the hole concentration decreases inp-Bi2-xFexTe3, while the electron concentration increases inn-Bi2-xFexSe3.The hole concentration decreases in Sb2-xCrxTe3with Cr doping. This demonstrates that Fe or Cr act as donors. The Seebeck coefficient increases inp-Bi2-xFexTe3and Sb2-xCrxTe3with increasing Fe or Cr content, while it decreases inn-Bi2-xFexSe3.

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Thermoelectric Lead Telluride with ZnO Nanoparticles

Фізика і хімія твердого тіла ◽

10.15330/pcss.16.1.62-67 ◽

2015 ◽

Vol 16 (1) ◽

pp. 62-67

Author(s):

O. M. Matkivsky

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Seebeck Coefficient ◽

Figure Of Merit ◽

Lead Telluride ◽

Thermoelectric Figure Of Merit ◽

X Ray Diffraction ◽

Thermoelectric Figure ◽

X Ray ◽

Zno Powder

An X-ray diffraction structural study and measurement of Seebeck coefficient (S), the electrical conductivity (σ) and thermal conductivity (χ) for Lead Telluride with nanoinclusions of ZnO. The calculated value of the specific thermoelectric power (S2σ) and thermoelectric figure of merit (ZT). It was established that the addition of ZnO powder Nanodispersed diameter grains (40-60) nm PbTe reduces the thermal conductivity of the material, and at 0.5 wt.% ZnO to an increase of lead telluride thermoelectric figure of merit to ZT≈1,3.

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Влияние температуры спекания на термоэлектрические свойства соединения Bi-=SUB=-1.9-=/SUB=-Gd-=SUB=-0.1-=/SUB=-Te-=SUB=-3-=/SUB=-

Физика и техника полупроводников ◽

10.21883/ftp.2019.05.47550.08 ◽

2019 ◽

Vol 53 (5) ◽

pp. 620

Author(s):

М.Н. Япрынцев ◽

А.Е. Васильев ◽

О.Н. Иванов

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Seebeck Coefficient ◽

Elemental Composition ◽

Figure Of Merit ◽

Sintering Temperature ◽

Thermoelectric Figure Of Merit ◽

Total Thermal Conductivity ◽

Thermoelectric Figure ◽

Antisite Defects

AbstractThe regularities of the influence of the sintering temperature (750, 780, 810, and 840 K) on the elemental composition, crystal-lattice parameters, electrical resistivity, Seebeck coefficient, total thermal conductivity, and thermoelectric figure of merit of the Bi_1.9Gd_0.1Te_3 compound are investigated. It is established that the elemental composition of the samples during high-temperature sintering varies due to intense tellurium evaporation, which can lead to the formation of various point defects (vacancies and antisite defects) affecting the majority carrier (electron) concentration and mobility. The sintering temperature greatly affects the electrical resistivity of the samples, while the influence on the Seebeck coefficient and total thermal conductivity is much weaker. The largest thermoelectric figure of merit ( ZT ≈ 0.55) is observed for the sample sintered at 750 K.

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Carrier Pocket Engineering for the Design of Low Dimensional Thermoelectrics with High Z3DT

MRS Proceedings ◽

10.1557/proc-626-z4.3 ◽

2000 ◽

Vol 626 ◽

Cited By ~ 2

Author(s):

Takaaki Koga ◽

Stephen B. Cronin ◽

Mildred S. Dresselhaus

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Seebeck Coefficient ◽

Figure Of Merit ◽

Thermoelectric Figure Of Merit ◽

Engineering Model ◽

Thermoelectric Figure ◽

Model Calculations ◽

Low Dimensional ◽

Good Agreement

ABSTRACTThe concept of carrier pocket engineering applied to Si/Ge superlattices is tested experimentally. A set of strain-symmetrized Si(20Å)/Ge(20Å) superlattice samples were grown by MBE and the Seebeck coefficient S, electrical conductivity σ, and Hall coefficient were measured in the temperature range between 4K and 400K for these samples. The experimental results are in good agreement with the carrier pocket engineering model for temperatures below 300K. The thermoelectric figure of merit for the entire superlattice, Z3DT, is estimated from the measured S and σ, and using an estimated value for the thermal conductivity of the superlattice. Based on the measurements of these homogeneously doped samples and on model calculations, including the detailed scattering mechanisms of the samples, projections are made for δ-doped and modulation-doped samples [(001) oriented Si(20Å)/Ge(20Å) superlattices] to yield Z3DT ≈ 0.49 at 300K.

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Variations of thermoelectric performance by electric fields in bilayer MX2 (M = W, Mo; X = S, Se)

Physical Chemistry Chemical Physics ◽

10.1039/c6cp05952j ◽

2017 ◽

Vol 19 (8) ◽

pp. 5797-5805 ◽

Cited By ~ 9

Author(s):

Rui-Ning Wang ◽

Guo-Yi Dong ◽

Shu-Fang Wang ◽

Guang-Sheng Fu ◽

Jiang-Long Wang

Keyword(s):

Electrical Conductivity ◽

Seebeck Coefficient ◽

Electric Fields ◽

Electronic Structures ◽

Figure Of Merit ◽

The Other ◽

Thermoelectric Figure Of Merit ◽

Two Dimensional ◽

Thermoelectric Figure ◽

Two Dimensional Materials

A gate is usually used to controllably tune the carrier concentrations, further modulating the electrical conductivity and Seebeck coefficient to obtain the optimum thermoelectric figure of merit in two-dimensional materials. On the other hand, it is necessary to investigate how an electric field induced by a gate affects the electronic structures, further determining the thermoelectric properties.

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