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Journal articles
Thermoelectric properties of TiS2 mechanically alloyed compounds
Abstract : Bulk polycrystalline samples in the series Ti1-xNbxS2 (0 ≤ x ≤ 0.075) were prepared using mechanical alloying synthesis and spark plasma sintering. X-ray diffraction analysis coupled with high resolution transmission electron microscopy indicates the formation of trigonal TiS2 by high energy ball-milling. The as-synthesized particles consist of pseudo-ordered TiS2 domains of around 20-50 nm, joined by bent atomic planes. This bottom-up approach leads, after spark plasma sintering, to homogeneous solid solutions, with a niobium solubility limit of x = 0.075. Microstructural observations evidence the formation of small crystallites in the bulk compounds with a high density of stacking faults. The large grain boundary concentration coupled with the presence of planar defects, leads to a substantial decrease in the thermal conductivity to 1.8 W/mK at 700 K. This enables the figure of merit to reach ZT = 0.3 at 700 K for x = 0.05, despite the lower electron mobility in mechanically alloyed samples due to small crystallite/grain size and structural defects. © 2015 Elsevier Ltd.
https://hal-normandie-univ.archives-ouvertes.fr/hal-02184700
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Submitted on : Tuesday, July 16, 2019 - 11:29:15 AM
Last modification on : Wednesday, November 3, 2021 - 7:04:34 AM
Contributor : Université Normandie Connect in order to contact the contributor
Submitted on : Tuesday, July 16, 2019 - 11:29:15 AM
Last modification on : Wednesday, November 3, 2021 - 7:04:34 AM
