Improving thermoelectric performance of TiNiSn by mixing MnNiSb in the half-Heusler structure

Berry T, Ouardi S, Fecher GH, Balke B, Kreiner G, Auffermann G, Schnelle W, Felser C (2017)

Publication Type: Journal article

Publication year: 2017

Journal

Physical Chemistry Chemical Physics Royal Society of Chemistry

Book Volume: 19

Pages Range: 1543-1550

Journal Issue: 2

DOI: 10.1039/c6cp06859f

Abstract

The thermoelectric properties of the n-type semiconductor TiNiSn were optimized by partial substitution with metallic MnNiSb in the half Heusler structure. Herein, we study the transport properties and intrinsic phase separation in the Ti1-xMnxNiSn1-xSbx system. The alloys were prepared by arc-melting and annealed at temperatures obtained from differential thermal analysis and differential scanning calorimetry results. The phases were characterized using powder X-ray diffraction patterns, energy-dispersive X-ray spectroscopy, and differential scanning calorimetry. After annealing, the majority phase was TiNiSn with some Ni-rich sites, and the minority phases were primarily Ti6Sn5, Sn and MnSn2. The Ni-rich sites were caused by Frenkel defects; this led to metal-like behavior in the semiconductor specimens at low temperature. For x ≤ 0.05 the samples showed an activated conduction, whereas for x > 0.05 they showed metallic character. The figure of merit for x = 0.05 was increased by 61% (zT = 0.45) in comparison with the pure TiNiSn.

Involved external institutions

Max-Planck-Institut für Chemische Physik fester Stoffe (MPI CPfS) / Max Planck Institute for Chemical Physics of Solids DE Germany (DE) Johannes Gutenberg-Universität Mainz (JGU) DE Germany (DE)

How to cite

APA:

Berry, T., Ouardi, S., Fecher, G.H., Balke, B., Kreiner, G., Auffermann, G.,... Felser, C. (2017). Improving thermoelectric performance of TiNiSn by mixing MnNiSb in the half-Heusler structure. Physical Chemistry Chemical Physics, 19(2), 1543-1550. https://doi.org/10.1039/c6cp06859f

MLA:

Berry, T., et al. "Improving thermoelectric performance of TiNiSn by mixing MnNiSb in the half-Heusler structure." Physical Chemistry Chemical Physics 19.2 (2017): 1543-1550.

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