Exploring the thermoelectric behavior of spark plasma sintered Fe7-xCoxS8 compounds

JOURNAL OF ALLOYS AND COMPOUNDS

卷:819

Article

Simon, Juliette^1,2  Guelou, Gabin^1,2  Srinivasan, Bhuvanesh^1,2,3  Berthebaud, David^3,4  Mori, Takao^1,2,5  Maignan, Antoine⁴ 

[1] Natl Inst Mat Sci, WPI Int Ctr Mat Nanoarchitechton WPI MANA, Namiki 1-1, Tsukuba, Ibaraki 3050044, Japan

[2] Natl Inst Mat Sci, Ctr Funct Sensor & Actuator CFSN, Namiki 1-1, Tsukuba, Ibaraki 3050044, Japan

[3] Natl Inst Mat Sci, CNRS St Gobain NIMS, UMI 3629, Lab Innovat Key Mat & Struct LINK, Tsukuba, Ibaraki 3050044, Japan

[4] Normandie Univ, Lab CRISMAT, ENSICAEN, UNICAEN,CNRS, F-14000 Caen, France

[5] Univ Tsukuba, Grad Sch Pure & Appl Sci, Tsukuba, Ibaraki 3058671, Japan

关键词: Co-doped pyrrhotites;    Sulfides;    SPS;    Thermoelectrics;    Structural transition;    Improved power factor;   

DOI  :  10.1016/j.jallcom.2019.152999

来源: Elsevier

【 摘 要 】

Sulfide-based materials are emerging as viable alternatives for the current state-of-the-art thermoelectric materials, which usually are composed of toxic, expensive and scarce elements. Here, a systematic study of one such inexpensive and environmentally friendly sulfide-based system, i.e. Fe7-xCoxS8 pyrrhotite-type compounds that were synthesized by solid-state reaction and densifled by Spark Plasma Sintering are investigated for their structural and thermoelectric properties. We report that substitution of Co for Fe in pyrrhotites: (i) induces structural transition from monoclinic 4C superstructure to trigonal 3C superstructure; (ii) modifies the magnetic behavior by decreasing the magnetic ordering temperature and magnetization; (iii) alters the type of dominant charge carriers (from p-to n-type) and enhances their electrical transport properties; (iv) mitigates the phonon contribution to the thermal conductivity; and (v) amplifies the thermoelectric figure of merit when compared with that of pristine pyrrhotites. (C) 2019 Elsevier B.V. All rights reserved.

【 授权许可】

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