Thermoelectric Generating Properties of Aurivillius Compounds

Thermoelectric generator is expected as an independent source, an energy converter for co-generation with Refuse Derived Fuel (RDF) and so on. Thermoelectric materials were required high Seebeck coefficient, low electrical resistivity and low thermal conductivity. Thermoelectric oxides are suitable at the high temperature range because of chemical stability. Authors focus attention on Aurivillius compounds. The Aurivillius compounds consist of Perovskite layers and Bi-O layers. It is expected that nano-layered structure shows high Seebeck coefficient due to the quantum confinement of electron in Perovskite layers. It was reported that the Seebeck coefficient of Aurivillius phase Bi2VO5.5 was high value of -28.3 mVK-1 at 1010 K, and the electrical resistivity of the one was also high value of 0.033 Ωm at 1010 K. We investigated about element substitution effects at V site on thermoelectric properties. Bi2V1-xMxO5.5 (M=Cu, Cr, x=0, 0.05, 0.1, 0.2) were prepared by solid-state reaction and hot pressing. From the results of the electrical resistivities and the Seebeck coefficients, Cu and Cr behaved as acceptor to Bi2VO5.5. Cr was effective for reducing the thermal conductivity of Bi2VO5.5. The maximum value of dimensionless figure of merit for Bi2VO5.5 was 0.06 at 910 K.

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Thermoelectric Properties of Semiconducting Intermetallic Compounds: FeGa3and RuGa3

MRS Proceedings ◽

10.1557/proc-793-s8.38 ◽

2003 ◽

Vol 793 ◽

Author(s):

Y. Amagai ◽

A. Yamamoto ◽

C. H. Lee ◽

H. Takazawa ◽

T. Noguchi ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

High Temperature ◽

Seebeck Coefficient ◽

Transport Properties ◽

Figure Of Merit ◽

Room Temperature ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

High Seebeck Coefficient

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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Thermoelectric Properties of Cr3S4-Type Selenides

MRS Proceedings ◽

10.1557/proc-545-333 ◽

1998 ◽

Vol 545 ◽

Cited By ~ 9

Author(s):

G. Jeffrey Snyder ◽

T. Caillat ◽

J. -P. Fleurial

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Seebeck Coefficient ◽

Thermoelectric Properties ◽

Lattice Thermal Conductivity ◽

Structure Type ◽

Seebeck Coefficients

AbstractSeveral compounds with the Cr3S4 structure type have been studied for their thermoelectric properties. All exhibit low lattice thermal conductivity of about 15 mW/cmK, independent of temperature. Many of the compounds, such as Co3Se4, Ni3Se4, Fe3Se4, Ti3Se4, FeNi2Se4, and FeCo2Se4, are metals with relatively low electrical resistivity and Seebeck coefficient. The Cr containing compounds, such as Cr3Se4, NiCr2Se4, CoCr2Se4, and FeCr2Se4, have the largest Seebeck coefficients and highest resistivity. thermoelectric applications is FeCr2Se4.

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Influence of R3+ ion sizes on the thermoelectric properties of RBaCo4O7+δ ceramics

Modern Physics Letters B ◽

10.1142/s0217984915501547 ◽

2015 ◽

Vol 29 (26) ◽

pp. 1550154 ◽

Cited By ~ 4

Author(s):

F. Gao ◽

Q. L. He ◽

F. Wu ◽

D. L. Yang ◽

X. Hu ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Solid State ◽

Thermoelectric Properties ◽

Solid State Reaction ◽

Solid State Reaction Method ◽

Oxygen Adsorption ◽

Reaction Method ◽

Transition Phenomenon ◽

Seebeck Coefficients

The influence of [Formula: see text] ion sizes on the electrical resistivity, Seebeck coefficients, thermal conductivity and [Formula: see text] values of [Formula: see text] prepared by the solid-state reaction method was investigated from 373 K to 973 K. The electrical resistivity decreases with decreasing [Formula: see text] ion sizes. Both the electrical resistivity and the Seebeck coefficients have a transition at about 630 K. Especially, the transition phenomenon disappears gradually with decreasing [Formula: see text] ion sizes, and is attributed to the oxygen adsorption of [Formula: see text]. The [Formula: see text] values increase with rising temperature or decreasing [Formula: see text] ion sizes. The [Formula: see text] with the smallest [Formula: see text] size has the maximum [Formula: see text] value that reaches 0.1 at 973 K.

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Thermoelectric Properties of Doped Iron Disilicide

MRS Proceedings ◽

10.1557/proc-626-z8.1 ◽

2000 ◽

Vol 626 ◽

Author(s):

Jun-ichi Tani ◽

Hiroyasu Kido

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Seebeck Coefficient ◽

Thermoelectric Properties ◽

Measured Temperature ◽

Iron Disilicide ◽

Measured Temperature Range ◽

Temperature Range

ABSTRACTIn order to investigate the thermoelectric properties of Re-doped β-FeSi2 (Fe1-xRexSi2), Ir-doped β-FeSi2 (Fe1-xIrxSi2), and Pt-doped β-FeSi2 (Fe1-xPtxSi2), the electrical resistivity, the Seebeck coefficient, and the thermal conductivity of these samples have been measured in the temperature range between 300 and 1150 K. Fe1-xRexSi2 is p-type, while Fe1-xIrxSi2 and Fe1-xPt xSi2 are n-type over the measured temperature range. The solubility limits of dopant are estimated to be 0.2at% for Fe1-xRexSi2, 0.5at% for Fe1-xIrxSi2, and 1.9at% for Fe1-xPtxSi2. A maximum ZT value of 0.14 was obtained for Fe1-xPt xSi2 (x=0.03) at the temperature 847 K.

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High-temperature thermoelectric properties of W-substituted CaMnO3

MRS Proceedings ◽

10.1557/opl.2013.85 ◽

2013 ◽

Vol 1490 ◽

pp. 3-8 ◽

Cited By ~ 2

Author(s):

Dimas S. Alfaruq ◽

James Eilertsen ◽

Philipp Thiel ◽

Myriam H Aguirre ◽

Eugenio Otal ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

High Temperature ◽

Seebeck Coefficient ◽

Thermoelectric Properties ◽

Soft Chemistry ◽

Absolute Seebeck Coefficient

AbstractThe thermoelectric properties of W-substituted CaMn1-xWxO3-δ (x = 0.01, 0.03; 0.05) samples, prepared by soft chemistry, were investigated from 300 K to 1000 K and compared to Nb-substituted CaMn0.98Nb0.02O3-δ. All compositions exhibit both an increase in absolute Seebeck coefficient and electrical resistivity with temperature. Moreover, compared to the Nb-substituted sample, the thermal conductivity of the W-substituted samples was strongly reduced. This reduction is attributed to the nearly two times greater mass of tungsten. Consequently, a ZT of 0.19 was found in CaMn0.97W0.03O3-δ at 1000 K, which was larger than ZT exhibited by the 2% Nb-doped sample.

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(Invited) Thin Film Thermoelectric Metal-Organic Framework with High Seebeck Coefficient and Low Thermal Conductivity

ECS Meeting Abstracts ◽

10.1149/ma2015-02/28/1063 ◽

2015 ◽

Keyword(s):

Thin Film ◽

Thermal Conductivity ◽

Seebeck Coefficient ◽

Metal Organic Framework ◽

Low Thermal Conductivity ◽

Metal Organic ◽

High Seebeck Coefficient ◽

Organic Framework

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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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3D Integration of Si-Based Peltier Device onto 4H-SiC Power Device

Materials Science Forum ◽

10.4028/www.scientific.net/msf.858.1107 ◽

2016 ◽

Vol 858 ◽

pp. 1107-1111 ◽

Cited By ~ 1

Author(s):

Yutaka Furubayashi ◽

Takafumi Tanehira ◽

Kei Yonemori ◽

Nobuhide Seo ◽

Shinichiro Kuroki

Keyword(s):

Thermal Conductivity ◽

Seebeck Coefficient ◽

Schottky Barrier ◽

High Thermal Conductivity ◽

Power Device ◽

3D Integration ◽

Process Flow ◽

Suitable Material ◽

High Seebeck Coefficient ◽

Peltier Device

We propose 3-D integration of Peltier device onto a power device. In order to transport a heat from the power device, as a suitable material of the Peltier device, silicon was adopted because of its high Seebeck coefficient, high thermal conductivity, and applicability to semiconductor process. Bulk Si-based Peltier devices with conventional shape showed an active thermal transport over a Joule heat at the operation current less than 5 A. 3-D integration of 4H-SiC-based Schottky barrier diodes and Si-based film Peltier device, separated by intrinsic SiC layer, was realized by using conventional Si-based process flow.

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Performance and Testing of Novel Quantum Well Thermoelectric Devices

Volume 5: Energy Systems Analysis, Thermodynamics and Sustainability; NanoEngineering for Energy; Engineering to Address Climate Change, Parts A and B ◽

10.1115/imece2010-40842 ◽

2010 ◽

Author(s):

Velimir Jovanovic ◽

Saeid Ghamaty ◽

Norbert B. Elsner ◽

Daniel Krommenhoek ◽

John C. Bass

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Quantum Well ◽

Seebeck Coefficient ◽

Coefficient Of Performance ◽

Test Technique ◽

Low Thermal Conductivity ◽

Barrier Materials ◽

Te Modules ◽

Conversion Efficiencies

New nano-structured thermoelectric (TE) materials have been developed and fabricated that have much higher conversion efficiencies than the state-of-the-art (SOTA) bulk thermoelectrics. In these new quantum well (QW) materials, the carrier and barrier materials (in this case SiGe and Si) are confined in alternating layers less than 10 nm thick, and this confinement has been shown to result in greatly improved TE properties (Seebeck coefficient, electrical resistivity and thermal conductivity) leading to higher TE Figure of Merit, ZT, conversion efficiencies and Coefficient of Performance (COP) for cooling applications than for SOTA thermoelectrics. From the most recent QW test data, ZTs greater than 3 at room temperature have been obtained which constitutes a significant improvement over the SOTA bulk thermoelectrics which have ZTs less than 1. QW materials have the best measured TE power factor (Seebeck coefficient squared divided by electrical resistivity) and, combined with low thermal conductivity substrates, should provide very high efficiency TE modules. The QW TE materials with ZTs greater than 3 lead to conversion efficiencies greater than 20 percent, which allows for much wider commercial applications, particularly in the applications such as the waste-heat recovery from truck engines, refrigeration, and air conditioning, where the SOTA bulk TE modules were shown to be technically feasible but economically unjustified due to low conversion efficiencies. With higher efficiency QW materials, these applications become economically attractive. The above mentioned QW TE ZTs include the effect of the substrate which degrades the overall performance, and a new test technique was developed that eliminates the effect of the substrate and for just the QW films, ZTs greater than 6 have been measured. This illustrated the importance of using a low thermal conductivity substrate in order to achieve good TE performance. In a recent QW test, a conversion efficiency corresponding to 62 percent of the Carnot efficiency was measured and this is believed to be the highest such value ever measured for a TE material. For power generation applications, QW TE generators can be designed for capacities ranging from milliwatts to kilowatts and for cooling applications with capacities ranging from watts to several tons of refrigeration. The paper discusses the effects of the thermal and electrical contact resistances and of substrate thermal conductivity on the TE performance, the status of the prototype QW TE generators and coolers being designed and fabricated, and the latest test results.

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