Control of electrical to thermal conductivity ratio for p-type LaxFe3CoSb12 thermoelectrics by using a melt-spinning process

Geonsik Son, Kyu Hyoung Lee, Hae Woong Park, Arnaud Caron, Il Ho Kim, Soonil Lee, Soon Mok Choi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

In this work we improved the thermoelectric figure of merit ZT in a LaxCoFe3Sb12 (x = 0.80, 0.85, 0.90) skutterudite system by applying a conductivity ratio (electrical to thermal) control method based on the phonon-glass electron-crystal (PGEC) approach. Polycrystalline bulks of LaxCoFe3Sb12 were prepared by melt-spinning and subsequent spark plasma sintering. Based on the thermoelectric transport properties and microstructural analysis, we found that large amount of La-filler (x ≥ 0.9) in the LaxCoFe3Sb12 system is necessary to increase the conductivity ratio required to improve the thermoelectric properties in the LaxCoFe3Sb12 system. Resultantly, the maximum ZT value of 0.87 was obtained at 723 K in the heavily filled La0.9CoFe3Sb12. We discuss our results on the basis of the filling level dependence of the rattling effect and on the formation of the skutterudite single phase. We also confirm that a large amount of La-filling level is necessary to meet the electrical neutrality condition of the p-type LaxCoFe3Sb12 skutterudite system.

Original languageEnglish
Pages (from-to)1209-1214
Number of pages6
JournalJournal of Alloys and Compounds
Volume729
DOIs
Publication statusPublished - 2017 Jan 1

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All Science Journal Classification (ASJC) codes

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

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