Thermal conductivity, electrical resistivity, and dimensionless figure of merit (ZT) determination of thermoelectric materials by impedance spectroscopy up to 250 °C

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).

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Effect of Ni in new skutterudite compounds CaxCo4Sb12

MRS Proceedings ◽

10.1557/proc-793-s4.1 ◽

2003 ◽

Vol 793 ◽

Cited By ~ 1

Author(s):

Matthieu Puyet ◽

Bertrand Lenoir ◽

Anne Dauscher ◽

Hubert Scherrer ◽

Moukrane Dehmas ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Thermal Properties ◽

Beneficial Effect ◽

Transport Properties ◽

Figure Of Merit ◽

Positive Influence ◽

Temperature Range ◽

Dimensionless Figure Of Merit ◽

Ni Substitution

ABSTRACTThe transport properties of the partially filled CaxCo4-yNiySb12 skutterudite compounds have been investigated in the 300 – 800 K temperature range. We underline the positive influence of the Ni substitution on the electrical resistivity and thermopower while the thermal properties – thermal conductivity – remains almost unaffected. These results suggest again a beneficial effect of Ni atoms on the dimensionless figure of merit in CoSb3 based compounds.

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Influence of contact resistance and heat leakage in the determination of the dimensionless figure of merit via duo-impedance spectroscopy

Japanese Journal of Applied Physics ◽

10.35848/1347-4065/ac1f48 ◽

2021 ◽

Author(s):

Shinya Hirabayashi ◽

Yasuhiro Hasegawa

Keyword(s):

Impedance Spectroscopy ◽

Contact Resistance ◽

Figure Of Merit ◽

Dimensionless Figure Of Merit ◽

Heat Leakage

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Thermoelectric properties of hole-doped Yb1-xPbxBaCo4O7+δ ceramics

International Journal of Modern Physics B ◽

10.1142/s0217979215500824 ◽

2015 ◽

Vol 29 (14) ◽

pp. 1550082 ◽

Cited By ~ 6

Author(s):

Yubo Chen ◽

Runxiang Ma ◽

Kunlun Wang ◽

Feng Gao ◽

Xing Hu ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Solid State ◽

Figure Of Merit ◽

Solid State Reaction Method ◽

Doping Content ◽

Reaction Method ◽

Dimensionless Figure Of Merit ◽

Ceramic Samples ◽

Pb Doping

The effects of Pb doping on the thermoelectric (TE) properties of Yb 1-x Pb x BaCo4O7+δ (x = 0, 0.02, 0.04, 0.06, 0.08 and 0.1) ceramic samples prepared by the solid-state reaction method were investigated from 383 K to 973 K. The results showed that with increase of the Pb content, the electrical resistivity decreased remarkably, meanwhile the Seebeck coefficient decreased slightly, resulting in an enhancement of the power factor (PF). The effect of Pb doping on the thermal conductivity was insignificant. According to the PF and the dimensionless figure of merit (ZT) value, the optimum Pb doping content was x = 0.08. The ZT value reached 0.12 at 973 K, being 69.5% higher than that of the sample without Pb doping.

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Thermoelectric Properties of La-doped BaSi2 and (Ba,Sr)Si2 Solid Solutions

MRS Proceedings ◽

10.1557/proc-1044-u06-12 ◽

2007 ◽

Vol 1044 ◽

Author(s):

Kohsuke Hashimoto ◽

Ken Kurosaki ◽

Hiroaki Muta ◽

Shinsuke Yamanaka

Keyword(s):

Thermal Conductivity ◽

Solid Solution ◽

Electrical Resistivity ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Room Temperature ◽

Dimensionless Figure Of Merit ◽

Plasma Sintering ◽

Spark Plasma ◽

La Doped

AbstractWe studied the thermoelectric properties of BaSi2 and SrSi2. The polycrystalline samples were prepared by spark plasma sintering (SPS). The electrical resistivity (ρ), Seebeck coefficient (S), and thermal conductivity (κ) were measured above room temperature. The maximum values of the dimensionless figure of merit (ZT) were 0.01 at 954 K for BaSi2 and 0.09 at 417 K for SrSi2. We tried to enhance the ZT values of BaSi2 and SrSi2 by prepareing and characterizing La-doped BaSi2 and (Ba,Sr)Si2 solid solution.

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COMPARISON OF HARMAN AND COOLING COUPLE METHODS FOR Z DETERMINATION

Canadian Journal of Physics ◽

10.1139/p66-081 ◽

1966 ◽

Vol 44 (5) ◽

pp. 971-985 ◽

Cited By ~ 1

Author(s):

W. B. Muir

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Temperature Difference ◽

Thermoelectric Materials ◽

Figure Of Merit ◽

Maximum Temperature ◽

Maximum Temperature Difference ◽

Type Apparatus

A Peltier–Seebeck or Harman type apparatus has been constructed to measure the Seebeclc coefficient, α, thermal conductivity, κ, electrical resistivity, ρ, and the figure of merit, Z, of thermoelectric materials over the range of temperature 150–300 °K while maintaining the sample in an approximately isothermal environment. Errors in the measured values of ρ, Z, α, and κ have been kept within 1, 1.5, 3, and 5% respectively. A comparison of the maximum temperature difference, ΔTmax, measured in a cooling test and the value of ΔTmax calculated from the values of α, κ, and ρ as a function of temperature measured in the Harman apparatus shows that, for five thermocouples, agreement is obtained within 1.2 °K on the average, with the greatest disparity being 2.5 °K.

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Thermoelectric properties of the Al-TM-Si (TM = Mn, Re) 1/1-cubic approximant

MRS Proceedings ◽

10.1557/proc-805-ll3.3 ◽

2003 ◽

Vol 805 ◽

Cited By ~ 1

Author(s):

Tsunehiro Takeuchi ◽

Toshio Otagiri ◽

Hiroki Sakagami ◽

Uichiro Mizutani

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Room Temperature ◽

Low Thermal Conductivity ◽

Dimensionless Figure Of Merit

ABSTRACTThe electrical resistivity, thermoelectric power, and thermal conductivity were investigated for the Al71.6-xMn 17.4Six and Al71.6-xRe 17.4Six (7 ≤ x ≤ 12) 1/1-cubic approximants. A large thermoelectric power ranging from -40 to 90 μV/K and a low thermal conductivity less than 3 W/K·cm were observed at room temperatures. The electrical resistivity at room temperature for these approximants was kept below 4,000 μΩcm, that is much smaller than that in the corresponding quasicrystals. As a result of the large thermoelectric power, the low thermal conductivity, and the low electrical resistivity, large dimensionless figure of merit ZT = 0.10 (n-type) and 0.07 (p-type) were achieved for the Al71.6Re17.4Si11 and Al71.6Mn17.4Si11 at room temperature, respectively.

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The thermoelectric properties of CoSb3 compound doped with Te and Sn synthesized at different pressure

Modern Physics Letters B ◽

10.1142/s021798491750261x ◽

2017 ◽

Vol 31 (28) ◽

pp. 1750261 ◽

Cited By ~ 2

Author(s):

Yiping Jiang ◽

Xiaopeng Jia ◽

Hongan Ma

Keyword(s):

Thermal Conductivity ◽

High Pressure ◽

Electrical Resistivity ◽

High Temperature ◽

Seebeck Coefficient ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Raw Materials ◽

Absolute Value ◽

Dimensionless Figure Of Merit

The skutterudite CoSb[Formula: see text]Te[Formula: see text]Sn[Formula: see text] compound was synthesized successfully by high pressure and high temperature (HPHT) method using Co, Sb, Te and Sn powder as raw materials. The effects of pressure on its structure and the thermoelectric properties are investigated systematically from 300 K to 800 K. The electrical resistivity and the absolute value of the Seebeck coefficient for the sample increases with rising synthetic pressure. The thermal conductivity of the sample decreases with synthetic pressure and temperature rising in the range of 300–800 K. In this study, the maximum dimensionless figure of merit (ZT) value of 1.17 has been achieved at 793 K, 3 GPa for this thermoelectric material.

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FEM Analysis on Thermoelectric Properties of Metal/TiO2–x Composites with Random Distribution of Metal Powder

Materials Science Forum ◽

10.4028/www.scientific.net/msf.750.130 ◽

2013 ◽

Vol 750 ◽

pp. 130-133

Author(s):

Katsuhiro Sagara ◽

Yun Lu ◽

Dao Cheng Luan

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Seebeck Coefficient ◽

Thermoelectric Properties ◽

Power Factor ◽

Figure Of Merit ◽

Random Distribution ◽

The Other ◽

Dimensionless Figure Of Merit ◽

Wide Range

Analysis model of finite element method with a random distribution for thermoelectric composites was built. Thermoelectric properties including electrical resistivity, Seebeck coefficient and thermal conductivity of M/TiO2–x (M = Cu, Ni, 304 stainless steel (304SS)) thermoelectric composites were investigated by the proposed model. Cu/TiO2–x composite showed a large decrease in electrical resistivity while 304SS/TiO2–x composite thermal conductivity was slightly increased. Calculated dimensionless figure-of-merit, ZT of Ni/TiO2–x composite was higher than those of TiO2–x and the other composites in a wide range of metal volume fractions because Ni has large absolute values of Seebeck coefficient, power factor and dimensionless figure-of-merit compared to the other two metals. It was found that power factor and dimensionless figure-of-merit of thermoelectric composites depended on the balance among electrical resistivity, thermal conductivity and Seebeck coefficient. The results revealed that it is important for M/TiO2–x composites to choose suitable addition metal with high power factor and dimensionless figure-of-merit.

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