Thermoelectric performance of higher manganese silicide nanocomposites
2015 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, Vol. 619, 31-37 p.Article in journal (Refereed) Published
Higher manganese silicides (HMS) are proven to be promising candidates as p-type thermoelectric material in the temperature range of 400-700 K. In this work, a series of nanostructured (NS) bulk MnSi1.73 with different levels of Ytterbium inclusions were fabricated via ball milling and the solid state reaction was completed by spark plasma sintering (SPS). Nanopowders and SPS consolidated Yb-HMS nanocomposites (NC) were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) to reveal the crystal structure and morphology respectively. High resolution transmission electron microscopy (HRTEM) coupled with energy dispersive X-ray spectroscopy (EDS) was used to investigate the material composition in bulk grains. Yb was observed to stay as nanoinclusions at the grain boundaries. TE transport properties, including Seebeck coefficient, electrical resistivity, and thermal diffusivity as well as charge carrier concentrations were evaluated. Thermal conductivity decreased with increasing Yb content, while the electrical conductivity improved for the highest Yb content. A highest figure of merit (ZT) of 0.42 at 600 degrees C was achieved for 1% Yb-HMS NC sample.
Place, publisher, year, edition, pages
2015. Vol. 619, 31-37 p.
Thermoelectrics, Higher manganese silicide, Spark plasma sintering, Nanostructured
IdentifiersURN: urn:nbn:se:kth:diva-157585DOI: 10.1016/j.jallcom.2014.09.016ISI: 000344429000007ScopusID: 2-s2.0-84907572358OAI: oai:DiVA.org:kth-157585DiVA: diva2:771261
FunderSwedish Foundation for Strategic Research , EM11-0002Swedish Energy Agency, 36656-1
QC 201412122014-12-122014-12-112014-12-12Bibliographically approved