Thermoelectric Properties of Fe-Doped CoSb3 Prepared by Encapsulated Induction Melting and Hot Pressing

2007 ◽  
Vol 534-536 ◽  
pp. 1557-1560 ◽  
Author(s):  
Kwan Ho Park ◽  
Jung Il Lee ◽  
Soon Chul Ur ◽  
Il Ho Kim
Keyword(s):  
Heat Treatment ◽  
Thermoelectric Properties ◽  
Hot Pressing ◽  
Single Phase ◽  
Electron Acceptors ◽  
Subsequent Heat Treatment ◽  
Optimum Composition ◽  
Induction Melting

The encapsulated induction melting and hot pressing were employed to prepare the Fedoped CoSb3 skutterudites and their thermoelectric properties were investigated. Single phase δ- CoSb3 was successfully obtained by the subsequent heat treatment at 773K for 24 hours. Iron atoms acted as electron acceptors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by the appropriate doping. Co0.7Fe0.3Sb3 was found as an optimum composition for best thermoelectric properties in this work.

Thermoelectric Properties of Co1-xFexSb3 Prepared by Encapsulated Induction Melting

2007 ◽  
Vol 124-126 ◽  
pp. 939-942 ◽  
Author(s):  
Kwan Ho Park ◽  
Soon Chul Ur ◽  
Il Ho Kim
Keyword(s):  
Heat Treatment ◽  
Thermoelectric Properties ◽  
Single Phase ◽  
Solubility Limit ◽  
Subsequent Heat Treatment ◽  
Optimum Composition ◽  
Induction Melting ◽  
Fe Doping ◽  
Seebeck Coefficients ◽  
P Type

Co1-xFexSb3 skutterudites were synthesized by encapsulated induction melting and their thermoelectric properties were investigated. Single phase δ-CoSb3 was successfully obtained by the subsequent heat treatment at 773K for 24 hours in vacuum. However, δ-CoSb3 was decomposed to FeSb2 and Sb when x≥0.3, which means that the solubility limit of Fe to Co is x<0.3. The positive signs of Seebeck coefficients for all Fe-doped specimens revealed that Fe atoms acted as p-type dopants by substituting Co atoms. Thermoelectric properties were remarkably enhanced by Fe doping and optimum composition was found to be Co0.7Fe0.3Sb3 in this study.

Thermoelectric Properties of Ni-Doped CoSb3 Prepared by Encapsulated Induction Melting and Hot Pressing

2007 ◽  
Vol 534-536 ◽  
pp. 1561-1564 ◽  
Author(s):  
Mi Jung Kim ◽  
Jung Il Lee ◽  
Soon Chul Ur ◽  
Il Ho Kim
Keyword(s):  
Heat Treatment ◽  
Thermoelectric Properties ◽  
Hot Pressing ◽  
Single Phase ◽  
Subsequent Heat Treatment ◽  
Electron Donors ◽  
Induction Melting ◽  
Doping Effects

Ni-doped CoSb3 was prepared by the encapsulated induction melting and hot pressing, and its doping effects on the thermoelectric properties were investigated. Single phase δ-CoSb3 was successfully obtained by the subsequent heat treatment at 773K for 24 hours. Nickel atoms acted as electron donors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by the appropriate doping.

Thermoelectric Properties of Skutterudite CoSb3 Prepared by Encapsulated Induction Melting

2007 ◽  
Vol 544-545 ◽  
pp. 921-924
Author(s):  
Soon Chul Ur ◽  
Il Ho Kim
Keyword(s):  
Heat Treatment ◽  
Phase Transitions ◽  
Thermoelectric Properties ◽  
Single Phase ◽  
Induction Melting ◽  
Isothermal Heat Treatment

Encapsulated induction melting was attempted to prepare binary skutterudite CoSb3 and its thermoelectric properties were investigated. Single phase δ-CoSb3 was successfully obtained by the subsequent isothermal heat treatment at 773K-873K for 24 hours in vacuum. Thermoelectric properties were changed with constituent phases because β-CoSb and Sb are metallic/semimetallic phases, while γ-CoSb2 and δ-CoSb3 are semiconducting phases. Thermoelectric properties were remarkably improved by the proper heat treatment and they were closely related to phase transitions.

scholarly journals Mechanical and Thermoelectric Properties of Bulk AlSb Synthesized by Controlled Melting, Pulverizing and Subsequent Vacuum Hot Pressing

2019 ◽  
Vol 9 (8) ◽  
pp. 1609 ◽  
Author(s):  
A. K. M. Ashiquzzaman Shawon ◽  
Soon-Chul Ur
Keyword(s):  
Mechanical Properties ◽  
Intermetallic Compound ◽  
Thermoelectric Properties ◽  
Hot Pressing ◽  
Single Phase ◽  
Aluminum Antimonide ◽  
Simple Method ◽  
Group Iii ◽  
Indirect Band Gap ◽  
First Time

Aluminum antimonide is a semiconductor of the Group III-V order. With a wide indirect band gap, AlSb is one of the least discovered of this family of semiconductors. Bulk synthesis of AlSb has been reported on numerous occasions, but obtaining a single phase has always proven to be extremely difficult. This work reports a simple method for the synthesis of single-phase AlSb. Subsequently, consolidation was done into a near single-phase highly dense semiconductor in a form usable for thermoelectric applications. Further, the thermoelectric properties of this system are accounted for the first time. In addition, the mechanical properties of the intermetallic compound are briefly discussed for a possibility of further use.

Electronic Transport Properties of Tin-Filled Cobalt Antimonides

2007 ◽  
Vol 26-28 ◽  
pp. 891-894
Author(s):  
Jae Yong Jung ◽  
Soon Chul Ur ◽  
Il Ho Kim
Keyword(s):  
Heat Treatment ◽  
Transport Properties ◽  
Electronic Transport ◽  
Single Phase ◽  
Induction Melting ◽  
Isothermal Heat Treatment ◽  
Degenerate Semiconductor ◽  
Lattice Contribution ◽  
Electronic Transport Properties ◽  
P Type

The encapsulated induction melting was attempted to prepare the Sn-filled CoSb3 skutterudites and their electronic transport properties were investigated. Single phase δ-CoSb3 was successfully obtained by the subsequent isothermal heat treatment at 823K for 6 days in vacuum. The Sn-filled CoSb3 showed p-type conductivity at 300K to 700K at it is a highly degenerate semiconductor. Lattice contribution was dominant to thermal conductivity and it was considerably reduced by Sn filling in the CoSb3 skutterudite.

Synthesis and Thermoelectric Properties of CoSb3-yTey

2008 ◽  
Vol 55-57 ◽  
pp. 829-832
Author(s):  
Soon Chul Ur ◽  
Il Ho Kim
Keyword(s):  
Thermoelectric Properties ◽  
Figure Of Merit ◽  
Single Phase ◽  
Electron Donors ◽  
Subsequent Annealing ◽  
Induction Melting ◽  
Dimensionless Figure Of Merit ◽  
Doping Effects

Te-doped CoSb3 was prepared by the encapsulated induction melting, and its doping effects on the thermoelectric properties were investigated. Single phase d-CoSb3 was successfully obtained by the subsequent annealing at 773K for 24 hours. Tellurium atoms acted as electron donors by substituting antimony atoms. Thermoelectric properties were remarkably improved by the appropriate doping. Dimensionless figure of merit was obtained to be 0.83 at 700K for the CoSb2.8Te0.2 specimen.

Thermoelectric Properties of Nanostructured CoSb3 Synthesized by Mechanical Alloying

2007 ◽  
Vol 534-536 ◽  
pp. 1425-1428
Author(s):  
Soon Chul Ur ◽  
Joon Chul Kwon ◽  
Moon Kwan Choi ◽  
Soon Young Kweon ◽  
Tae Whan Hong ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Mechanical Alloying ◽  
Thermoelectric Properties ◽  
Hot Pressing ◽  
Figure Of Merit ◽  
Single Phase ◽  
Phonon Scattering ◽  
Stoichiometric Composition ◽  
Processing Route ◽  
Vacuum Hot Pressing

Undoped CoSb3 powders were synthesized by mechanical alloying of elemental powders using a nominal stoichiometric composition. Nanostructured, single-phase skutterudite CoSb3 was successfully produced by vacuum hot pressing using as-milled powders without subsequent annealing. Phase transformations during synthesis were investigated using XRD, and microstructure was observed using SEM and TEM. Thermoelectric properties in terms of Seebeck coefficient, electrical conductivity, thermal conductivity and figure of merit were systematically measured and compared with the results of analogous studies. Lattice thermal conductivity was reduced owing to increasing phonon scattering in nanostructured CoSb3, leading to enhancement in the thermoelectric figure of merit. Mechanical Alloying associated with vacuum hot pressing technique offers an alternative potential processing route for the production of skutterudites.

Mechanical Alloying and Thermoelectric Properties of CoSb3 Skutterudite

2005 ◽  
Vol 486-487 ◽  
pp. 642-645 ◽  
Author(s):  
Moon Kwan Choi ◽  
Soon Chul Ur ◽  
Joon Chul Kwon ◽  
K.W. Cho ◽  
Il Ho Kim ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Mechanical Alloying ◽  
Phase Transformations ◽  
Thermoelectric Properties ◽  
Hot Pressing ◽  
Single Phase ◽  
Stoichiometric Composition ◽  
Subsequent Annealing ◽  
Vacuum Hot Pressing ◽  
Temperature Dependences

In an effort to synthesize homogenized single phase d-CoSb3, this study considers the mechanical alloying (MA) of elemental Co and Sb powders using a nominal stoichiometric composition followed by hot pressing. Single phase, undoped CoSb3 skutterudites were successfully produced by vacuum hot pressing using MA powders without subsequent annealing. Phase transformations during mechanical alloying, powder annealing, and hot pressing were systematically investigated using XRD and SEM. Thermoelectric properties were measured and compared with the results of similar studies. Temperature dependences were also evaluated, and their correlations to phase transformation were examined.

Sign in / Sign up

Export Citation Format

Share Document