Fine tuning of thermoelectric performance in phase-separated half-Heusler compounds

Rausch E, Balke B, Stahlhofen JM, Ouardi S, Burkhardt U, Felser C (2015)

Publication Type: Journal article

Publication year: 2015

Journal

Journal of Materials Chemistry C Royal Society of Chemistry

Book Volume: 3

Pages Range: 10409-10414

Journal Issue: 40

DOI: 10.1039/c5tc01196e

Abstract

Two successful recipes to enhance the thermoelectric performance, namely carrier concentration optimization and reduction of thermal conductivity, have been combined and applied to the p-type (Ti/Zr/Hf)CoSb1-xSnx system. An intrinsic micrometer-scale phase separation increases the phonon scattering and reduces the lattice thermal conductivity. A substitution of 15% Sb by Sn optimizes the electronic properties. Starting from this, further improvement of the thermoelectric properties has been achieved by a fine tuning of the Ti to Hf ratio. The microstructuring of the samples was studied in detail with high-resolution synchrotron powder X-ray diffraction and element mapping electron microscopy. Linking the structural with the thermoelectric properties, a record thermoelectric figure of merit for p-type half-Heusler compounds of ZT ≈ 1.2 at 710 °C in Ti0.25Hf0.75CoSb0.85Sn0.15 was achieved. The phase separation approach can form a significant alternative to nanostructuring processing, saving time, energy consumption and increasing the thermoelectric efficiency.

Involved external institutions

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

How to cite

APA:

Rausch, E., Balke, B., Stahlhofen, J.M., Ouardi, S., Burkhardt, U., & Felser, C. (2015). Fine tuning of thermoelectric performance in phase-separated half-Heusler compounds. Journal of Materials Chemistry C, 3(40), 10409-10414. https://doi.org/10.1039/c5tc01196e

MLA:

Rausch, Elisabeth, et al. "Fine tuning of thermoelectric performance in phase-separated half-Heusler compounds." Journal of Materials Chemistry C 3.40 (2015): 10409-10414.

BibTeX: Download