The Effect of Rh and Sr Substitution on the Thermoelectric Performance of LaCoO3

AbstractA series of LaCo1-xRhxO3 (x=0-1) samples and La1-ySryCo1-xRhxO3 (y = 0.05, 0.15 and x = 0.1-0.3) samples were prepared to study the effect of Rh substituion for Co in the four component system and Sr substitution for La in the five component system on the crystal structure and thermoelectric performance of the LaCoO3. At Rh substitution for Co of x=0.2 greater, the crystal structure shifts from rhombohederal (LaCoO3) to orthorhombic (LaRhO3). Thermoelectric evaluation revealed that Rh doped samples (0.3 <x <1) show large positive seebeck coefficients indicating a P-type conduction in the temperature range of the tests (273 to 775K). Rh substitution for Co decreases thermal conductivity, increases Seebeck coefficient and consequently increases the theroelectric figure of merit ZT. Sr substitution for La increases thermal and electrical conductivity and consquenently negligiblely decreases the seebeck coefficient. A thermoelectric figure-of-merit (ZT) around 0.075 has been achieved for LaCo0.5Rh0.5O3 at 775 K, and is expected to be above 0.1 at 1000 K. Sr substitution improved the TE properties throughout the lower temperature range with a ZT =0.045 observed for La0.95Sr0.05Co0.9Rh0.1O3 at 425 K and ZT = 0.05 for La0.85Sr0.15Co0.5Rh0.5O3 at 775 K. These findings provide new insight into thermoelectric perovskite oxides containing rhodium and strontium.

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Improving the thermoelectric performance of p-type PbSe via synergistically enhancing the Seebeck coefficient and reducing electronic thermal conductivity

Journal of Materials Chemistry A ◽

10.1039/c9ta13927c ◽

2020 ◽

Vol 8 (9) ◽

pp. 4931-4937 ◽

Cited By ~ 2

Author(s):

Zhiwei Huang ◽

Dongyang Wang ◽

Caiyun Li ◽

Jinfeng Wang ◽

Guangtao Wang ◽

...

Keyword(s):

Thermal Conductivity ◽

Seebeck Coefficient ◽

Thermoelectric Performance ◽

Seebeck Coefficients ◽

Electronic Thermal Conductivity ◽

P Type

CdTe alloying dramatically enhanced the thermoelectric performance of p-type PbSe by enhancing Seebeck coefficients and reducing electronic thermal conductivity.

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Thermal expansion of alunite up to dehydroxylation and collapse of the crystal structure

Mineralogical Magazine ◽

10.1180/minmag.2012.076.3.12 ◽

2012 ◽

Vol 76 (3) ◽

pp. 613-623 ◽

Cited By ~ 8

Author(s):

M. Zema ◽

A. M. Callegari ◽

S. C. Tarantino ◽

E. Gasparini ◽

P. Ghigna

Keyword(s):

Crystal Structure ◽

Thermal Expansion ◽

Potassium Cation ◽

Cell Parameters ◽

Temperature Range ◽

Thermal Expansion Coefficients ◽

Volume Dilatation ◽

Lower Temperature Range ◽

Lower Temperature ◽

A Minor

AbstractThe high-temperature (HT) behaviour of a sample of natural alunite was investigated by means of in situ HT single-crystal X-ray diffraction from room temperature up to the dehydroxylation temperature and consequent collapse of the crystal structure. In the temperature range 25–500°C, alunite expands anisotropically, with most of the contribution to volume dilatation being produced by expansion in the c direction. The thermal expansion coefficients determined over the temperature range investigated are: αa = 0.61(2) × 10–5 K–1 (R2 = 0.988), αc = 4.20(7) × 10–5 K–1 (R2 = 0.996), αc/αa = 6.89, αV = 5.45(7) × 10–5 K–1 (R2 = 0.998). At ∼275–300°C, a minor discontinuity in the variation of unit-cell parameters with temperature is observed and interpreted on the basis of loss of H3O+ that partially substitutes for K+ at the monovalent A site in the alunite structure. Increasing temperature causes the Al(O,OH)6 sheets, which remain almost unaltered along the basal plane, to move further apart, and this results in an expansion of the coordination polyhedron around the intercalated potassium cation. Sulfate tetrahedra act as nearly rigid units, they contract a little in the lower temperature range to accommodate the elongation of the Al octahedra.

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SEEBECK COEFFICIENTS OF Mn-Si MATERIALS PREPARED BY SPARK PLASMA SINTERING

International Journal of Modern Physics B ◽

10.1142/s0217979204026123 ◽

2004 ◽

Vol 18 (16) ◽

pp. 2279-2286 ◽

Cited By ~ 16

Author(s):

ZHI MIN WANG ◽

YI DONG WU ◽

YUAN JIN HE

Keyword(s):

Seebeck Coefficient ◽

Spark Plasma Sintering ◽

X Ray Diffraction ◽

X Ray ◽

Temperature Range ◽

Seebeck Coefficients ◽

Plasma Sintering ◽

Pure Phase ◽

Spark Plasma ◽

P Type

MnSi 1.73 and MnSi samples were grown by spark plasma sintering (SPS) from different Si / Mn ratio powders, at different sintering temperatures, and for different sintering times. X-ray diffraction (XRD) measurements showed samples containing MnSi and MnSi 1.73 and Si phases, depending on the initial stoichiometries. Measurements of the Seebeck coefficient revealed p-type conductance for all samples. The Seebeck coefficients of the samples with MnSi pure phase were very low (about 10 μ V/K) and changed little at the temperature range measured. The Seebeck coefficients of the samples with MnSi 1.73, MnSi and Si phases were similar to that of the sample with near-pure MnSi 1.73 phase, which were larger than those of the samples with MnSi 1.73 and MnSi phases, but a little smaller than those of the samples with MnSi 1.73 and Si phases. It seems that, for the samples with the same phases, larger ratio of the strongest intensity peak of MnSi 1.73 to [Formula: see text], MnSi 1.73 to [Formula: see text] or both lead to larger Seebeck coeffiecients.

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High Thermoelectric Performance of p-Type Bi0.5Sb1.5Te3+xTe Crystals Prepared via Gradient Freezing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.621.167 ◽

2012 ◽

Vol 621 ◽

pp. 167-171

Author(s):

Tao Hua Liang ◽

Shi Qing Yang ◽

Zhi Chen ◽

Qing Xue Yang

Keyword(s):

Thermal Conductivity ◽

Seebeck Coefficient ◽

Carrier Concentration ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Room Temperature ◽

Thermoelectric Performance ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

P Type

p-type Bi0.5Sb1.5Te3+xTe thermoelectric crystals with various percentages of Te (x = 0.00 wt.%–3.00 wt.%) excess were prepared by the gradient freeze method. By doping with different Te contents, anti-site defects, Te vacancies and hole carrier concentrations were controlled. The Seebeck coefficient, resistivity, thermal conductivity, carrier concentration, and mobility were measured. The relationships between the Te content and thermoelectric properties were investigated in detail. The results suggested that the thermoelectric figure of merit ZT of the Bi0.5Sb1.5Te3+0.09wt.% crystals was 1.36 near room temperature, the optimum carrier concentration was 1.25 × 1019 cm-3, and the mobility was 1480 cm2 V-1 S-1, respectively.

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Crystal structure and thermoelectric performance of p−type Bi0.86Ba0.14CuSeO/Cu2−Se composites

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2021.04.016 ◽

2021 ◽

Author(s):

H.Y. Hong ◽

D.H. Kim ◽

S.O. Won ◽

J.K. Lee ◽

S.D. Park ◽

...

Keyword(s):

Crystal Structure ◽

Thermoelectric Performance ◽

P Type

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OXYCHALCOGENIDES AS NEW EFFICIENT p-TYPE THERMOELECTRIC MATERIALS

Functional Materials Letters ◽

10.1142/s1793604713400079 ◽

2013 ◽

Vol 06 (05) ◽

pp. 1340007 ◽

Cited By ~ 4

Author(s):

CELINE BARRETEAU ◽

LIN PAN ◽

YAN-LING PEI ◽

LI-DONG ZHAO ◽

DAVID BERARDAN ◽

...

Keyword(s):

Figure Of Merit ◽

Parent Compound ◽

Thermoelectric Figure ◽

Medium Temperature ◽

Temperature Range ◽

The Past ◽

Thermoelectric Conversion ◽

New Directions ◽

Wide Scale ◽

P Type

During the past two years, we have underlined the great potential of p-type oxychalcogenides, with parent compound BiCuSeO , for thermoelectric applications in the medium temperature range (400–650°C). These materials, which do not contain lead and are less expensive than Te containing materials, exhibit large thermoelectric figure of merit, exceeding 1 in a wide temperature range, mainly due to an intrinsically very low thermal conductivity. This paper summarizes the main chemical and crystallographic features of this system, as well as the thermoelectric properties. It also gives new directions to improve these properties, and discuss the potential of these materials for wide scale applications in thermoelectric conversion system in the medium temperature range.

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

Journal of Materials Research ◽

10.1557/jmr.2009.0058 ◽

2009 ◽

Vol 24 (2) ◽

pp. 430-435 ◽

Cited By ~ 29

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.

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Formability and Process Conditions of Magnesium Alloy Sheets

Materials Science Forum ◽

10.4028/www.scientific.net/msf.488-489.453 ◽

2005 ◽

Vol 488-489 ◽

pp. 453-456 ◽

Cited By ~ 11

Author(s):

Shi Hong Zhang ◽

Yong Chao Xu ◽

G. Palumbo ◽

S. Pinto ◽

Luigi Tricarico ◽

...

Keyword(s):

Deep Drawing ◽

Tensile Tests ◽

Process Conditions ◽

Drawing Ratio ◽

Temperature Range ◽

Fine Grained ◽

Axial Tensile ◽

Die Surface ◽

Lower Temperature Range ◽

Lower Temperature

Comparing the formability with each other, extrusion and various rolling experiments were carried out to make fine-grained AZ31 Mg sheets, and uni-axial tensile tests were carried out at different strain rates and temperatures to investigate the effect of different variables. A warm deep drawing tool setup with heating elements, which were distributed under the die surface and inside the blank holder, was designed and manufactured, and deep drawing was performed. Extruded Mg alloy AZ31 sheets exhibit the best deep drawing ability when working in the temperature range 250-350°C. Extruded and rolled sheets of 0.8 mm thick were also deep drawn in the lower temperature range 105-170°C，showing good formability and reaching a Limit Drawing Ratio up to 2.6 at 170°C for rolled sheets. At last, a sheet cup 0.4 mm thick was deep drawn successfully at 170 °C.

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