Influence of dopant size and doping method on the structure and thermoelectric properties of PBTTT films doped with F6TCNNQ and F4TCNQ

Thermoelectric properties of steel slag-carbon fiber/cement composites were studied in this paper. The effect of steel slag content on thermoelectric properties was focused on especially. The experimental results show that the addition of steel slag leads to an increase in the positive thermoelectric power of the cabon fiber/cement composites. The highest absolute thermoelectric power of carbon fiber/cement composites was rendered as positive as 14.4µV/°C by using steel slag, which had a high concentration of holes. Beside, a good linear relationship was observed between thermoelectric power and temperature differential on the specimen.

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Power generation performance of π-structure thermoelectric device using NaCo2O4 and Mg2Si elements

MRS Proceedings ◽

10.1557/opl.2013.53 ◽

2013 ◽

Vol 1490 ◽

pp. 185-190 ◽

Cited By ~ 1

Author(s):

Tomoyuki Nakamura ◽

Kazuya Hatakeyama ◽

Masahiro Minowa ◽

Youhiko Mito ◽

Koya Arai ◽

...

Keyword(s):

Power Generation ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Waste Heat ◽

Maximum Output Power ◽

Magnesium Silicide ◽

Thermoelectric Device ◽

Maximum Output ◽

Thermoelectric Power Generation ◽

P Type

ABSTRACTThermoelectric power generation has been attracting attention as a technology for waste heat utilization in which thermal energy is directly converted into electric energy. It is well known that layered cobalt oxide compounds such as NaCo2O4 and Ca3Co4O9 have high thermoelectric properties in p-type oxide semiconductors. However, in most cases, the thermoelectric properties in n-type oxide materials are not as high. Therefore, n-type magnesium silicide (Mg2Si) has been studied as an alternative due to its non-toxicity, environmental friendliness, lightweight property, and comparative abundance compared with other TE systems. In this study, we fabricated π-structure thermoelectric power generation devices using p-type NaCo2O4 elements and n-type Mg2Si elements. The p- and n-type sintering bodies were fabricated by spark plasma sintering (SPS). To reduce the resistance at the interface between elements and electrodes, we processed the surface of the elements before fabricating the devices. The end face of a Mg2Si element was covered with Ni by SPS and that of a NaCo2O4 element was coated with Ag by silver paste and soldering.The thermoelectric device consisted of 18 pairs of p-type and n-type legs connected with Ag electrodes. The cross-sectional and thickness dimensions of the p-type elements were 3.0 mm × 5.0 mm × 7.6 mm (t) and those of the n-type elements were 3.0 mm × 3.0 mm × 7.6 mm (t). The open circuit voltage was 1.9 V and the maximum output power was 1.4 W at a heat source temperature of 873 K and a cooling water temperature of 283 K in air.

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Effects of Cation Substitution on the Thermoelectric Properties in Ca-Co-O

MRS Proceedings ◽

10.1557/proc-691-g12.2 ◽

2001 ◽

Vol 691 ◽

Author(s):

Ichiro Matsubara ◽

Ryoji Funahashi ◽

Masahiro Shikano ◽

Kei Sasaki ◽

Hiroyuki Enomoto

Keyword(s):

Thin Films ◽

Solid Solution ◽

Thermoelectric Power ◽

Compressive Stress ◽

Thermoelectric Properties ◽

Plane Stress ◽

Solution Process ◽

Cation Substitution ◽

Combinatorial Approach ◽

Solid Solution Range

ABSTRACTWe have prepared (Ca1−x−yMxBiy)3Co4Oz (M = Mg, Sr, and Ba) thin films by a combinatorial approach using a solution process. In the systems of (Ca1−x−yMxBiy)3Co4Oz (M = Mg, Sr, and Ba), solid solution range was determined to be × < 0.8 (M = Sr, y = 0), x < 1.0 (M = Mg, y = 0), x = 0.0 (M = Ba, y = 0), and x < 0.4 (M = Bi, x = 0). No solid solution range was obtained for the substitution of Ba for Ca site. The in-plane compressive stress in the CoO2 sublattice is controllable by the cation substitution for Ca in the (Ca2CoO3) sublattice. With increasing in-plane stress, the magnitude of thermoelectric power and resistivity increased.

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Large thermoelectric power variations in epitaxial thin films of layered perovskite GdBaCo2O5.5±δ with a different preferred orientation and strain

Journal of Materials Chemistry A ◽

10.1039/d0ta04781c ◽

2020 ◽

Vol 8 (38) ◽

pp. 19975-19983

Author(s):

Arindom Chatterjee ◽

Emigdio Chavez-Angel ◽

Belén Ballesteros ◽

José Manuel Caicedo ◽

Jessica Padilla-Pantoja ◽

...

Keyword(s):

Thin Films ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Tensile Strain ◽

Preferred Orientation ◽

Oxygen Stoichiometry ◽

Layered Perovskite ◽

Epitaxial Thin Films ◽

P Type

Oxygen stoichiometry in epitaxial GdBaCo2O5.5±δ films accommodates the strain, which substantially affects thermoelectric properties, bringing the material from p-type (tensile strain c⊥-oriented on STO) to n-type thermopower (compressive b⊥ on LAO).

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Improving the thermoelectric power factor of CNT/PEDOT:PSS nanocomposite films by ethylene glycol treatment

RSC Advances ◽

10.1039/c6ra08599g ◽

2016 ◽

Vol 6 (58) ◽

pp. 53339-53344 ◽

Cited By ~ 53

Author(s):

Woohwa Lee ◽

Young Hun Kang ◽

Jun Young Lee ◽

Kwang-Suk Jang ◽

Song Yun Cho

Keyword(s):

Ethylene Glycol ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Power Factor ◽

Treatment Method ◽

Nanocomposite Films ◽

Thermoelectric Power Factor

This study investigates a treatment method with ethylene glycol for improving the thermoelectric properties of CNT/PEDOT:PSS nanocomposite films.

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Thermoelectric Properties of Mixed Rhenium Chalcogenides Re6Te15-x Sex (0 ≤ × ≤ 8)

MRS Proceedings ◽

10.1557/proc-545-197 ◽

1998 ◽

Vol 545 ◽

Author(s):

S. Kilibarda Dalafave ◽

J. Ziegler ◽

H. Mcallister

Keyword(s):

Thermoelectric Power ◽

Thermoelectric Properties ◽

Power Factor ◽

Room Temperature ◽

Energy Gap ◽

Selenium Concentration ◽

X Ray ◽

Tetragonal Lattice ◽

Factor Α ◽

Volume Decrease

AbstractReported are the temperature dependencies of the thermoelectric power and electrical resistivity of mixed rhenium chalcogenides Re6Te15-x,Sex (0 ≤ x ≤ 8) in the range 90–420 K. Influence of the partial chalcogen exchange on thermoelectric properties of these compounds is discussed. The samples are prepared by sintering elemental powders inside evacuated and sealed quartz ampoules at 1150 K for 170 hours. X-ray analysis reveals an orthorhombic lattice for samples with x < 8 and a tetragonal lattice for the Re6Te7Se8. sample. The lattice parameters and the unit cell volume decrease with increasing selenium concentration.The measurements indicate p-type semiconducting behavior for all samples. The presence of the energy gap is observed at higher temperatures (T ≥ 180–220 K) for all x. Data suggest hopping conduction at lower temperatures. Room temperature resistivities increase non-linearly from 6.9 to 20.4 Ω m with the increasing selenium content. Initially, the thermoelectric power a increases with temperature for all samples, with the fastest increase in Re6Se8 Te7 and the slowest in Re6Te15. The temperature at which a reaches maximum decreases with the increasing Se content. Above this temperature, a decreases uniformly as the temperature increases, the slowest increase being for Re6Se8Te7 and the fastest for Re6Te15. Such α(T) dependence is also discussed. The temperature dependence of the power factor, α2/ρ, is presented. Comparison of ρ, α, and the power factor in Re6SexTe15-x with currently used state-of-the-art materials is given.

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OPTIMIZATION OF THERMOELECTRIC PROPERTIES BY Cu SUBSTITUTION IN LaCoO3 CERAMICS

International Journal of Modern Physics B ◽

10.1142/s0217979214500659 ◽

2014 ◽

Vol 28 (09) ◽

pp. 1450065 ◽

Cited By ~ 1

Author(s):

K. K. CHOUDHARY ◽

N. KAURAV ◽

S. K. GHOSH

Keyword(s):

Thermal Conductivity ◽

Grain Boundaries ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Thermoelectric Figure Of Merit ◽

Linear Temperature Dependence ◽

Thermoelectric Figure ◽

Linear Temperature ◽

Cu Substitution

The thermoelectric properties of LaCo 1-x Cu x O 3-δ ceramics are theoretically analyzed, it is observed that thermoelectric figure of merit ZT ( = S2σT/κ) is maximized by Cu substitution in LaCo 1-x Cu x O 3-δ at x = 0.15. The lattice thermal conductivity (κ ph ) and phonon drag thermoelectric power [Formula: see text] were estimated by the scattering of phonons with defects, grain boundaries, electrons and phonon umklapp scattering to evaluate the thermoelectric figure of merit ZT. The Mott expression is used to estimate the electron diffusive thermoelectric power [Formula: see text] using Fermi energy as electron free parameter, [Formula: see text] shows linear temperature dependence. The electron contribution to thermal conductivity (κe) is estimated using temperature-dependent electron relaxation time. We found that Cu substitution increases the phonon scattering with grain boundaries and defects which significantly decrease the thermal conductivity and subsequently increase the thermoelectric power. The present numerical analysis of thermoelectric properties will help in designing more efficient thermoelectric materials for thermoelectric applications.

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Enhanced thermoelectric properties of PEDOT:PSS nanofilms by a chemical dedoping process

Journal of Materials Chemistry A ◽

10.1039/c3ta14960a ◽

2014 ◽

Vol 2 (18) ◽

pp. 6532-6539 ◽

Cited By ~ 167

Author(s):

Hongkwan Park ◽

Seung Hwan Lee ◽

Felix Sunjoo Kim ◽

Hyang Hee Choi ◽

In Woo Cheong ◽

...

Keyword(s):

Thin Films ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Conjugated Polymer ◽

Polymer Thin Films ◽

Post Processing ◽

Power Generators

Our results indicate that a well-designed simple post-processing process can boost the efficiency of thermoelectric power generators made of conjugated polymer thin films.

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Thermoelectric Properties of InxCo4-yNiySb12 Skutterudite Compounds

MRS Proceedings ◽

10.1557/proc-1044-u05-06 ◽

2007 ◽

Vol 1044 ◽

Cited By ~ 2

Author(s):

Veronique Da Ros ◽

Juliusz Leszczynski ◽

Bertrand Lenoir ◽

Anne Dauscher ◽

Christophe Candolfi ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Resistivity ◽

Thermal Properties ◽

Chemical Composition ◽

Thermoelectric Power ◽

Thermoelectric Properties ◽

Electron Probe Microanalysis ◽

Electron Probe ◽

X Ray Diffraction ◽

X Ray

AbstractThe preparation of partially filled n-type InxCo4Sb12 skutterudite compounds has been recently reported. The results were particularly promising, the materials exhibiting a ZT value far higher than one at moderated temperature. In this paper, we propose to investigate another way to tune the electrical and thermal properties by substituting Co atoms by Ni atoms in InxCo4Sb12. InxCo4-yNiySb12 polycrystalline samples have been prepared by a conventional metallurgical route. Structural analyses have been carried out by X-ray diffraction. The chemical composition and micro-homogeneity have been checked by electron probe microanalysis. Measurements of the electrical resistivity, thermoelectric power and thermal conductivity have been performed between 300 and 800 K. The influence of the presence of Ni on the thermoelectric properties of InxCo4Sb12 compounds is presented and discussed.

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