scholarly journals Optimizing thermocouple’s ZT through design innovation

2021 ◽  
Author(s):  
Tinggang Zhang
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Power Output ◽  
Doping Concentration ◽  
Optimal Combination ◽  
Original Design ◽  
The One ◽  
The Relationship

Abstract In this work, we demonstrate that in parallel with the one existed at high doping concentration, there also exists an optimal combination of the transport properties of a thermoelectric material at low doping concentration as the curve of the relationship between electrical conductivity and doping concentration is rigidly shifted toward lower doping concentration without disturbing the Seebeck coefficient and the thermal conductivity. Based on this finding, a new concept for thermocouple design is developed to improve the thermocouple’s efficiency and power output. The analytical model developed for the new thermocouple indicated that its efficiency and power output can be more than tripled as compared to those of the original design. A single thermocouple made of Silicon semiconductors was simulated numerically using different sets of input parameters. The results showed that the new thermocouple’s efficiency and power output can be improved significantly.

scholarly journals Optimizing thermocouple’s ZT through design innovation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tinggang Zhang
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Analytical Model ◽  
Power Output ◽  
Doping Concentration ◽  
Optimal Combination ◽  
Original Design ◽  
The One

AbstractThis work demonstrates that in parallel with the one existed at high doping concentration, there also exists an optimal combination of the transport properties of a thermoelectric material at low doping concentration as the curve of the relation between electrical conductivity and doping concentration is rigidly shifted toward that direction without disturbing the Seebeck coefficient and the thermal conductivity. Based on this finding, a new thermocouple design that uses low doping legs and high doping semiconductors as the external carrier injectors surrounding the legs is developed. The analytical model developed for the new thermocouple indicated that its efficiency and power output could be more than tripled as compared to those of the original design. A single thermocouple made of Silicon semiconductors was simulated numerically using different sets of input parameters. The results showed that the density of the externally injected carriers played a significant role in enhancing the thermocouple’s efficiency and power output.

scholarly journals Влияние легирования ванадием на термоэлектрические свойства сплавов Гейслера Fe-=SUB=-2-=/SUB=-Ti-=SUB=-1-x-=/SUB=-V-=SUB=-x-=/SUB=-Sn

2019 ◽  
Vol 53 (6) ◽  
pp. 777
Author(s):  
А.И. Таранова ◽  
А.П. Новицкий ◽  
А.И. Воронин ◽  
С.В. Таскаев ◽  
В.В. Ховайло
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Experimental Study ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Thermoelectric Properties ◽  
Pristine Sample ◽  
Electrical Conductivity Behavior ◽  
P Type ◽  
Conductivity Behavior

In this work the results of an experimental study of Fe2Ti1-xVxSn alloys (x = 0; 0.06; 0.15; 0.2) are presented. According to the temperature dependencies of the electrical conductivity, Seebeck coefficient and thermal conductivity, it is established, that the studied compositions exhibit transport properties typical for semiconductors. The substitution of V at the Ti site leads to a change of the p-type electrical conductivity behavior to n-type; the pristine sample of Fe2TiSn has the best thermoelectric properties.

scholarly journals Thermoelectric Properties of Bi2Te3: CuI and the Effect of Its Doping with Pb Atoms

2017 ◽  
Author(s):  
Mi-Kyung Han ◽  
Yingshi Jin ◽  
Da-Hee Lee ◽  
Sung-Jin Kim
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Carrier Concentration ◽  
Thermoelectric Properties ◽  
Thermal Transport ◽  
Co Doping ◽  
Thermal Transport Properties ◽  
Co Doped

In order to understand the effect of Pb-CuI co-doping on the thermoelectric performance of Bi2Te3, n-type Bi2Te3 co-doped with x at% CuI and 1/2x at% Pb (x = 0, 0.01, 0.03, 0.05, 0.07, and 0.10) were prepared via high temperature solid state reaction and consolidated using spark plasma sintering. Electron and thermal transport properties, i.e., electrical conductivity, carrier concentration, Hall mobility, Seebeck coefficient, and thermal conductivity, of CuI-Pb co-doped Bi2Te3 were measured in the temperature range from 300 K to 523 K and compared to corresponding x% of CuI-doped Bi2Te3 and undoped Bi2Te3. The addition of a small amount of Pb significantly decreased the carrier concentration, which could be attributed to the holes from Pb atoms, thus the CuI-Pb co-doped samples show a lower electrical conductivity and a higher Seebeck coefficient compared to CuI-doped samples with similar x values. The incorporation of Pb into CuI-doped Bi2Te3 rarely changed the power factor because of the trade-off relationship between the electrical conductivity and the Seebeck coefficient. The total thermal conductivity(κtot) of co-doped samples (κtot ~1.4 W/m∙K at 300 K) is slightly lower than that of 1% CuI-doped Bi2Te3 (κtot~1.5 W/m∙K at 300 K) and undoped Bi2Te3 (κtot ~1.6 W/m∙K at 300 K) due to the alloy scattering. The 1% CuI-Pb co-doped Bi2Te3 sample shows the highest ZT value of 0.96 at 370 K. All data on electrical and thermal transport properties suggest that the thermoelectric properties of Bi2Te3 and its operating temperature can be controlled by co-doping.

scholarly journals Imaging Thermoelectric Properties at the Nanoscale

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1199
Author(s):  
Stéphane Grauby ◽  
Aymen Ben Amor ◽  
Géraldine Hallais ◽  
Laetitia Vincent ◽  
Stefan Dilhaire
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Figure Of Merit ◽  
Quantitative Estimation ◽  
Conductivity Measurements ◽  
Thermal And Electrical Properties ◽  
Software And Hardware ◽  
Set Up ◽  
The One

Based on our previous experimental AFM set-up specially designed for thermal conductivity measurements at the nanoscale, we have developed and validated a prototype which offers two major advantages. On the one hand, we can simultaneously detect various voltages, providing, at the same time, both thermal and electrical properties (thermal conductivity, electrical conductivity and Seebeck coefficient). On the other hand, the AFM approach enables sufficient spatial resolution to produce images of nanostructures such as nanowires (NWs). After a software and hardware validation, we show the consistency of the signals measured on a gold layer on a silicon substrate. Finally, we demonstrate that the imaging of Ge NWs can be achieved with the possibility to extract physical properties such as electrical conductivity and Seebeck coefficient, paving the way to a quantitative estimation of the figure of merit of nanostructures.

scholarly journals Anisotropy and inhomogeneity measurement of the transport properties of spark plasma sintered thermoelectric materials

2012 ◽  
Vol 1490 ◽  
pp. 89-95 ◽  
Author(s):  
A. Jacquot ◽  
M. Rull ◽  
A. Moure ◽  
J.F. Fernandez-Lozano ◽  
M. Martin-Gonzalez ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Measurement System ◽  
Thermoelectric Materials ◽  
Simultaneous Measurement ◽  
Measurement Systems ◽  
Spark Plasma ◽  
Van Der Pauw

ABSTRACTWe report on the development and capabilities of two new measurement systems developed at Fraunhofer-IPM. The first measurement system is based on an extension of the Van der Pauw method and is suitable for cube-shaped samples. A mapping of the electrical conductivity tensor of a Skutterudite-SPS samples produced at the Instituto de Microelectrónica de Madrid is presented. The second measurement system is a ZTmeter also developed at the Fraunhofer-IPM. It enables the simultaneous measurement of the electrical conductivity, Seebeck coefficient and thermal conductivity up to 900 K of cubes at least 5x5x5 mm3 in size. The capacity of this measurement system for measuring the anisotropy of the transport properties of a (Bi,Sb)2Te3SPS sample produced by KTH is demonstrated by simply rotating the samples.

scholarly journals The Effect of Crystal Mismatch on the Thermoelectric Performance Enhancement of Nano Cu2Se

2021 ◽  
Vol 7 ◽  
Author(s):  
Yunus Demirci ◽  
Aminu Yusuf ◽  
Bejan Hamawandi ◽  
Muhammet S. Toprak ◽  
Sedat Ballikaya
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Performance Enhancement ◽  
Sem Analysis ◽  
Total Thermal Conductivity ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Two Phases

In the past decades, Cu2−xSe compounds have attracted great attention due to the inclusion of non-toxic and abundant elements, besides having a promising thermoelectric (TE) performance. In this work, we investigated the effect of a crystal mismatch of a nanoinclusion phase on the TE properties of Cu2−xSe. Nano-Cu2Se was synthesized using microwave assisted thermolysis, while the p-type skutterudite, Fe3.25Co0.75Sb12 (FeCoSb), compound was synthesized using a chemical alloying route. Nano-Cu2Se, and (nano-Cu2Se)1−x(nano-FeCoSb)x composites, where x = 0.05 and 0.1, were prepared via mechanical alloying followed by Spark Plasma Sintering process. Structural properties were evaluated by PXRD and SEM analysis, while the high temperature transport properties were examined via electrical conductivity, Seebeck coefficient, and thermal conductivity measurements in the temperature range of 300–800 K. Powder X-ray diffraction (PXRD) confirmed a single phase of nano Cu2Se, while the samples with FeCoSb inclusion consist of two phases as Cu2Se and CoSb3. SEM micrographs of all samples show that Cu2Se has randomly oriented grains with different sizes. Cu2Se samples with a FeCoSb inclusion show a rather different structure. In these samples, a rod-shaped FeCoSb phase, with a size varying between 20 and 100 nm, showed an inhomogeneous distribution in the structure and stacked between the Cu2Se layers. Transport data indicate that crystal mismatch between Cu2Se and FeCoSb has a strong effect on the TE transport properties. Electrical conductivity decreases but Seebeck coefficient enhances with nano FeCoSb inclusion. Total thermal conductivity was suppressed by 30% and ZT value enhanced by 15% with 5% nano FeCoSb inclusion at 750 K, likely due to a decrease in the electronic contribution of the thermal conductivity. Structural and transport data show that small amount of nanoinclusion of FeCoSb has a beneficial effect on the TE performance of nano Cu2Se at temperatures below 800 K.

Investigation of Thermoelectric Materials: Substitution effect of Bi on the Ag1-xPb18MTe20 (M = Sb, Bi) (x = 0, 0.14, 0.3)

2007 ◽  
Vol 1044 ◽  
Author(s):  
Mi-kyung Han ◽  
Huijun Kong ◽  
Ctirad Uher ◽  
Mercouri G Kanatzidis
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Thermoelectric Materials ◽  
Figure Of Merit ◽  
Lattice Thermal Conductivity ◽  
Substitution Effect ◽  
Dimensionless Figure Of Merit ◽  
The Matrix ◽  
Mass Fluctuation

AbstractWe performed comparative investigations of the Ag1-xPb18MTe20 (M = Bi, Sb) (x = 0, 0.14, 0.3) system to better understand the roles of Sb and Bi on the thermoelectric properties. In both systems, the electrical conductivity nearly keeps the same values, while the Seebeck coefficient decreases dramatically in going from Sb to Bi. Compared to the lattice thermal conductivity of PbTe, that of AgPb18BiTe20 is substantially reduced. The lattice thermal conductivity of the Bi analog, however, is higher than that of AgPb18SbTe20 and this is attributed largely to the decrease in the degree of mass fluctuation between the nanostructures and the matrix (for the Bi analog). As a result the dimensionless figure of merit ZT of Ag1-xPb18MTe20 (M = Bi) is found to be smaller than that of Ag1-xPb18MTe20 (M = Sb).

Thermoelectric Properties of Semiconducting Intermetallic Compounds: FeGa3and RuGa3

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.

Electronic Transport Properties of Hot-Pressed B6Si

1987 ◽  
Vol 97 ◽  
Author(s):  
C. Wood ◽  
D. Emin ◽  
R. S. Feigelson ◽  
I. D. R. Mackinnon
Keyword(s):  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Electronic Transport ◽  
Hall Mobility ◽  
Anomalous Behavior ◽  
Nominal Composition ◽  
Electronic Transport Properties ◽  
Increasing Temperature ◽  
P Type

ABSTRACTMeasurements of the electrical conductivity, Seebeck coefficient and Hall mobility from -300 K to -1300 K have been carried out on multiphase hotpressed samples of the nominal composition B6Si. In all samples the conductivity and the p-type Seebeck coefficient both increase smoothly with increasing temperature. By themselves, these facts suggest small-polaronic hopping between inequivalent sites. The measured Hall mobilities are always low, but vary in sign. A possible explanation is offered for this anomalous behavior.

Band Structure and Thermoelectric Properties of Ni(x)Zn(1-x)Fe2O4

2021 ◽  
Vol 317 ◽  
pp. 28-34
Author(s):  
Joon Hoong Lim
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Band Structure ◽  
Seebeck Coefficient ◽  
Band Gap ◽  
Thermoelectric Properties ◽  
Xrd Analysis ◽  
Valence Band Maximum ◽  
Solid State Method ◽  
Ni Content

Thermoelectric materials has made a great potential in sustainable energy industries, which enable the energy conversion from heat to electricity. The band structure and thermoelectric properties of Ni(x)Zn(1-x)Fe2O4 have been investigated. The bulk pellets were prepared from analytical grade ZnO, NiO and Fe2O3 powder using solid-state method. It was possible to obtain high thermoelectric properties of Ni(x)Zn(1-x)Fe2O4 by controlling the ratios of dopants and the sintering temperature. XRD analysis showed that the fabricated samples have a single phase formation of cubic spinel structure. The thermoelectric properties of Ni(x)Zn(1-x)Fe2O4 pellets improved with increasing Ni. The electrical conductivity of Ni(x)Zn(1-x)Fe2O4 pellets decreased with increasing Ni content. The electrical conductivity of Ni(x)Zn(1-x)Fe2O4 (x = 0.0) is (0.515 x10-3 Scm-1). The band structure shows that ZnxCu1-xFe2O4 is an indirect band gap material with the valence band maximum (VBM) at M and conduction band minimum (CBM) at A. The band gap of Ni(x)Zn(1-x)Fe2O4 increased with increasing Ni content. The increasing band gap correlated with the lower electrical conductivity. The thermal conductivity of Ni(x)Zn(1-x)Fe2O4 pellets decreased with increasing Ni content. The presence of Ni served to decrease thermal conductivity by 8 Wm-1K-1 over pure samples. The magnitude of the Seebeck coefficient for Ni(x)Zn(1-x)Fe2O4 pellets increased with increasing amounts of Ni. The figure of merit for Ni(x)Zn(1-x)Fe2O4 pellets and thin films was improved by increasing Ni due to its high Seebeck coefficient and low thermal conductivity.

Sign in / Sign up

Export Citation Format

Share Document