Electrical conductivity, electronic thermal conductivity, and thermo-EMF of an organic semiconductor

1971 ◽  
Vol 4 (3) ◽  
pp. 220-224
Author(s):  
S. I. Kubarev ◽  
M. I. Shchedrin
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Organic Semiconductor ◽  
Electronic Thermal Conductivity

scholarly journals DFT Study on the Carrier Concentration and Temperature-Dependent Thermoelectric Properties of Antimony Selenide

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Aditya Jayaraman ◽  
Abhijit Bhat Kademane ◽  
Muralikrishna Molli
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Thermoelectric Properties ◽  
Density Functional ◽  
Electronic Band Structure ◽  
Hole Concentration ◽  
Electronic Band ◽  
Electronic Thermal Conductivity ◽  
Increasing Temperature ◽  
Antimony Selenide

We present the thermoelectric properties of Antimony Selenide (Sb2Se3) obtained using first principles calculations. We investigated the electronic band structure using the FP-LAPW method within the sphere of the density functional theory. Thermoelectric properties were calculated using BoltzTrap code using the constant relaxation time (τ) approximation at three different temperatures 300 K, 600 K, and 800 K. Seebeck coefficient (S) was found to decrease with increasing temperature, electrical conductivity (σ/τ) was almost constant in the entire temperature range, and electronic thermal conductivity (κ/τ) increased with increasing temperature. With increase in temperature S decreased from 1870 μV/K (at 300 K) to 719 μV/K (at 800 K), electronic thermal conductivity increased from 1.56 × 1015 W/m K s (at 300 K) to 3.92 × 1015 W/m K s (at 800 K), and electrical conductivity decreased from 22 × 1019/Ω m s (at 300 K) to 20 × 1019/Ω m s (at 800 K). The thermoelectric properties were also calculated for different hole concentrations and the optimum concentration for a good thermoelectric performance over a large range of temperatures (from 300 K to 1000 K) was found for hole concentration around 1019 cm−3.

scholarly journals THE LOCALIZATION TRANSITION AT FINITE TEMPERATURES: ELECTRIC AND THERMAL TRANSPORT

2010 ◽  
Vol 24 (12n13) ◽  
pp. 1789-1810 ◽  
Author(s):  
Yoseph Imry ◽  
Ariel Amir
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Critical Exponent ◽  
Critical Behavior ◽  
Thermal Transport ◽  
Anderson Localization ◽  
Localization Transition ◽  
Electronic Thermal Conductivity

The Anderson localization transition is considered at finite temperatures. This includes the electrical conductivity as well as the electronic thermal conductivity and the thermoelectric coefficients. An interesting critical behavior of the latter is found. A method for characterizing the conductivity critical exponent, an important signature of the transition, using the conductivity and thermopower measurements, is outlined.

COPPER ALLOY No. 815

Alloy Digest ◽  
1977 ◽  
Vol 26 (5) ◽  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Corrosion Resistance ◽  
Physical Properties ◽  
Copper Alloy ◽  
Heat Treating ◽  
Chromium Alloy ◽  
High Electrical Conductivity ◽  
Medium Hardness ◽  
Hardened Condition

Abstract Copper Alloy No. 815 is an age-hardenable cast copper-chromium alloy. It is characterized by high electrical and thermal conductivities combined with medium hardness and strength in the age-hardened condition. It is used for components requiring high electrical conductivity or high thermal conductivity. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Cu-332. Producer or source: Copper alloy foundries.

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).

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.

Electronic Structure and Transport Properties of La2Zr2O7 Pyrochlore from First Principles

2018 ◽  
Vol 281 ◽  
pp. 767-773
Author(s):  
Zheng Li ◽  
Wei Pan
Keyword(s):  
Thermal Conductivity ◽  
Transport Properties ◽  
Electron Concentration ◽  
Boltzmann Transport ◽  
Principle Calculation ◽  
First Principle Calculation ◽  
Electronic Thermal Conductivity ◽  
Transport Calculation ◽  
Scattering Time ◽  
High Temperature Electronic

The first principle calculation as well as the Boltzmann transport calculation have been employed to study the high temperature electronic transport properties of pyrochlore La2Zr2O7. Combing constant scattering time approximation and experiment data, the electronic thermal conductivity and electron concentration are calculated as a function of temperature. The electronic thermal conductivity is 2.6×10-4 W/(m.s) at 1270K and 7.2×10-3 W/(m.s) at 1770K. The electron concentration increase rapidly with when the temperature is above 1600K.

Attaining reduced lattice thermal conductivity and enhanced electrical conductivity in as-sintered pure n-type Bi2Te3 alloy

2018 ◽  
Vol 54 (6) ◽  
pp. 4788-4797 ◽  
Author(s):  
Xiao-yu Wang ◽  
Hui-juan Wang ◽  
Bo Xiang ◽  
Hong-jing Shang ◽  
Bin Zhu ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Lattice Thermal Conductivity

Coupled Quantum-Scattering Madeling of Thermoelectric Properties of Si/Ge/Si Quantum Well Structures

2006 ◽  
Author(s):  
A. Bulusu ◽  
D. G. Walker
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Quantum Wells ◽  
Phonon Scattering ◽  
Local Density ◽  
Quantum Scattering ◽  
Local Density Of States ◽  
Quantum Well Structures ◽  
Optical Phonon Scattering ◽  
Non Equilibrium Green’S Function

Confined structures presumably offer enhanced performance of thermoelectric devices. 1) Interfaces and boundaries create scattering sites for phonons, which reduces the thermal conductivity. 2) Reduced dimensionality increases the local density of states near the Fermi level, which increases the Seebeck coefficient. From these two phenomena, the net effect should be an increase in ZT, the performance parameter used to evaluate different materials and structures. These effects have been measured and modeled, but none of the models attempts to quantify the electron-phonon coupled effects particularly in the regime where quantum and scattering influences are found. Using the non-equilibrium Green's function (NEGF) approach, quantum wells composed of Si and Ge are studied and the important physics isolated. Results show a competing effect between the decrease in the electrical conductivity due to scattering with the increase in electrical conductivity with doping, leading to 77% decrease in the value of the power factor for the case of electron-optical phonon scattering.

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