THE THERMAL CONDUCTIVITY OF PLATINUM BETWEEN 300 AND 1 000 °K

1966 ◽  
Vol 44 (12) ◽  
pp. 3173-3183 ◽  
Author(s):  
M. J. Laubitz ◽  
M. P. van der Meer
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
High Temperature ◽  
High Temperatures ◽  
Fermi Energy ◽  
High Purity ◽  
Lorenz Number ◽  
Increasing Function

The thermal conductivity of high-purity platinum was measured between 300 and 1 000 °K. The results obtained agree very well with the previously reported work of Bode and of Martin and Sidles, but at higher temperatures are in definite disagreement with the results of Powell and Tye. The observed variation of the thermal conductivity with temperature implies that at high temperatures the (electronic) Lorenz number of platinum is an increasing function of temperature, exceeding in magnitude the Sommerfeld value. Such behavior of the Lorenz number can be understood qualitatively if one assumes a low Fermi energy for platinum, an assumption usually made to account for the behavior of its high-temperature electrical resistivity.

Effects of Nb doping on thermoelectric properties of Zn4Sb3 at high temperatures

2009 ◽  
Vol 24 (2) ◽  
pp. 430-435 ◽  
Author(s):  
D. Li ◽  
H.H. Hng ◽  
J. Ma ◽  
X.Y. Qin
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
High Temperatures ◽  
Thermoelectric Properties ◽  
Figure Of Merit ◽  
Thermoelectric Performance ◽  
Temperature Range ◽  
A Value ◽  
Nb Doping ◽  
Thermal Conductivities

The thermoelectric properties of Nb-doped Zn4Sb3 compounds, (Zn1–xNbx)4Sb3 (x = 0, 0.005, and 0.01), were investigated at temperatures ranging from 300 to 685 K. The results showed that by substituting Zn with Nb, the thermal conductivities of all the Nb-doped compounds were lower than that of the pristine β-Zn4Sb3. Among the compounds studied, the lightly substituted (Zn0.995Nb0.005)4Sb3 compound exhibited the best thermoelectric performance due to the improvement in both its electrical resistivity and thermal conductivity. Its figure of merit, ZT, was greater than the undoped Zn4Sb3 compound for the temperature range investigated. In particular, the ZT of (Zn0.995Nb0.005)4Sb3 reached a value of 1.1 at 680 K, which was 69% greater than that of the undoped Zn4Sb3 obtained in this study.

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.

High-temperature thermoelectric properties of W-substituted CaMnO3

2013 ◽  
Vol 1490 ◽  
pp. 3-8 ◽  
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.

Thermoelectric properties of S-doped Cu2Se materials synthesized by high-pressure and high-temperature method

2019 ◽  
Vol 34 (01) ◽  
pp. 2050006
Author(s):  
Lisha Xue ◽  
Chao Fang ◽  
Weixia Shen ◽  
Manjie Shen ◽  
Wenting Ji ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
High Pressure ◽  
Electrical Resistivity ◽  
High Temperature ◽  
Thermoelectric Properties ◽  
Composition Change ◽  
Selenium Compounds ◽  
Competitive Effects ◽  
Temperature Method ◽  
Pressure Synthesis

High-pressure technique is an effective route to synthesize thermoelectric materials and tune transport properties simultaneously. In this work, S-doped copper–selenium compounds [Formula: see text], [Formula: see text] were successfully synthesized by high-pressure and high-temperature (HPHT) technology in just 30 min. [Formula: see text] samples show layered morphology composed of abundant pores and lattice defects. The appropriate S introduction ([Formula: see text] and 0.03) can effectively enhance Seebeck coefficient and reduce the thermal conductivity of [Formula: see text]. Compared with the pure [Formula: see text] sample, [Formula: see text] exhibits a 30% lower thermal conductivity, but the decline of power factor by the distinctly increased electrical resistivity at high temperature results in a smaller zT at temperature [Formula: see text] K. The variations of thermoelectric properties are resulted from the competitive effects between S-doping and actual composition change (Cu:S). It indicates that S-doping is not so effective in improving the zT value of [Formula: see text] materials by high-pressure synthesis.

Effect of Ho Doping on the High-Temperature Thermoelectric Properties of Ca3Co4O9-Based Oxides

2011 ◽  
Vol 228-229 ◽  
pp. 947-950
Author(s):  
Tao Zhu ◽  
Jun Min Zhou
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
High Temperature ◽  
Thermoelectric Properties ◽  
Lattice Thermal Conductivity ◽  
Solid Reaction

Ca3-xHoxCo4O9 (x=0.0, 0.15, 0.3, 0.45) samples were prepared using solid reaction and the effect of Ho doping on their high thermoelectric properties were investigated. The substitution of Ho for Ca resulted in an increase of both thermopower and electrical resistivity which could be attributed to the decrease of hole concentrations. The Ho-doped samples had lower thermal conductivity than Ca3Co4O9 due to their lower electronic and lattice thermal conductivity. The largest ZT values were attained in Ca2.7Ho0.3Co4O9 sample.

scholarly journals Electrical and thermal properties of silver nanowire fabricated on a flexible substrate by two-beam laser direct writing for designing a thermometer

RSC Advances ◽  
2018 ◽  
Vol 8 (44) ◽  
pp. 24893-24899 ◽  
Author(s):  
Gui-Cang He ◽  
Heng Lu ◽  
Xian-Zi Dong ◽  
Yong-Liang Zhang ◽  
Jie Liu ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
Thermal Properties ◽  
Temperature Dependence ◽  
Flexible Substrate ◽  
Silver Nanowire ◽  
Direct Writing ◽  
Laser Direct Writing ◽  
Lorenz Number ◽  
Beam Laser

Investigation of temperature dependence of electrical resistivity, thermal conductivity and Lorenz number of silver nanowire, and design of a thermometer.

Thermal Properties of Tungsten SRM’S 730 and 799

1978 ◽  
Vol 100 (2) ◽  
pp. 330-333 ◽  
Author(s):  
R. E. Taylor
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
Thermal Properties ◽  
High Temperature ◽  
Thermal Diffusivity ◽  
Thermophysical Properties ◽  
Room Temperature ◽  
Standard Material ◽  
International Program ◽  
Sintered Tungsten

Samples of sintered and arc-cast tungsten are available from NBS as thermal conductivity (SRM 730) and electrical resistivity (SRM 799) standards for the temperature range from 4 to 3000K. NBS recommended values for these properties above room temperature are based on results of various researchers during a previous international program which included arc-cast and sintered tungsten. The sintered tungsten used in this program was found to be unsuited for use as a standard material due to inhomogeneity and high temperature instability. The present paper gives results at high temperatures for thermal conductivity, electrical resistivity, specific heat, thermal diffusivity and Wiedemann-Franz-Lorenz ratio for a sample of the NBS sintered tungsten using the Properties Research Laboratory’s multiproperty apparatus. These results are compared to values recommended by the Thermophysical Properties Research Center, NBS, and an international program.

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