Thermoelectric Properties of Bulk Yttrium Silicide (YSi2) Fabricated by Arc Melting and Spark Plasma Sintering. Issue 6 (14th February 2018)

• Record Type: Journal Article
• Authors: Wongprakarn, Suphagrid; Pinitsoontorn, Supree; Tanusilp, Sora‐at; Kurosaki, Ken
• Is Part Of: Physica status solidi. Volume 215:Issue 6(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-02-14
• Subjects: silicides -- spark plasma sintering -- thermoelectric -- YSi2; Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.201700769
• Languages: English
• ISSNs: 1862-6300

Abstract

Abstract : Yttrium silicide (YSi2 ) nanoparticles in SiGe are reported to enhance the thermoelectric figure‐of‐merit ( ZT ) to the recorded value (≈1.81). However, the thermoelectric properties of bulk YSi2 has never been reported. In this work, the thermoelectric properties of YSi2 is studied for the first time. The bulk YSi2 is fabricated by arc melting highly pure Si and Y raw materials. The ingot is crushed to powder and compacted to form a highly dense pellet by spark plasma sintering. By optimizing the processing parameters, the single phase with the AlB2 ‐type structure ( P 6/ mmm ) is formed. The Hall measurements show that YSi2 exhibit a metallic‐like behavior with a very high electron concentration. This result in the thermoelectric properties with a very large electrical conductivity (≈18 × 10 5 Ω −1 m −1 ) but a small Seebeck coefficient (−26 µV K −1 ) at room temperature, and decrease with temperature. The thermal conductivity is around 14–19 W m −1 K −1 for all temperature range. The maximum ZT value is 0.026 at 423 K. Abstract : In recent years, silicide‐based materials have received increasing interests for thermoelectric applications. Yttrium silicide (YSi2 ) nanoparticles added in SiGe matrix show significant improvement in the thermoelectric figure‐of‐merit (ZT), and the SiGe‐YSi2 composites currently hold the recorded value for the silicide class. However, the thermoelectric properties of YSi2 have never been investigated. In this article, the thermoelectric study of bulk YSi2 is demonstrated for the first time.