Sustainable and simple processing technique for n-type skutterudites with high ZT and their analysis

Gerda Rogl, Kunio Yubuta, Michael Kerber, Andriy Grytsiv, Michael Zehetbauer, Ernst Bauer, Peter Rogl

研究成果: Contribution to journalArticle査読

13 被引用数 (Scopus)

抄録

As various branches of industry are interested in good thermoelectric generators, there is a serious demand for an easy, fast, cheap and sustainable production route of excellent thermoelectric materials. In this paper we demonstrate how we could achieve a high-ZT (ZT ∼ 1.45 at 823 K)n-type bulk skutterudite, (Mm,Sm)yCo4Sb12, by processing the industrially produced raw powder using a modified high-pressure torsion (HPT)equipment at elevated temperature under inert gas. For this HPT processed sample as well as for the annealed one, structural properties, especially focused on grain size and dislocation density (backed up by electron probe microanalysis, transmission electron microscopy investigations as well as XPD profile analysis), physical properties (from 300 to 823 K and for the electrical resistivity in addition from 4.2 to 300 K)and mechanical properties (elastic moduli, hardness, fracture resistance)were measured and evaluated and compared with the values of a traditionally prepared bulk material, using hot pressing (HP). As a consequence of severe plastic deformation, we found a change from metallic to semiconducting behavior during measurement induced annealing of the HPT processed skutterudite, which could be explained via the change of lattice distortion and its influence on the band gap. A positive ZT net effect occurred because although the electrical resistivity was enhanced the thermal conductivity was decreased. It turned out that the elastic moduli of the HPT samples were not much different from those of the HP skutterudite, however, that the hardness was significantly increased.

本文言語英語
ページ(範囲)9-19
ページ数11
ジャーナルActa Materialia
173
DOI
出版ステータス出版済み - 7 2019
外部発表はい

All Science Journal Classification (ASJC) codes

  • 電子材料、光学材料、および磁性材料
  • セラミックおよび複合材料
  • ポリマーおよびプラスチック
  • 金属および合金

フィンガープリント

「Sustainable and simple processing technique for n-type skutterudites with high ZT and their analysis」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル