Pressure-Induced Enhancement of Thermoelectric Figure of Merit and Structural Phase Transition in TiNiSn
Document Type
Article
Publication Date
1-20-2021
Publication Title
Journal of Physical Chemistry Letters
First page number:
1046
Last page number:
1051
Abstract
© 2020 American Chemical Society. Half-Heusler thermoelectric materials are potential candidates for high thermoelectric efficiency. We report high-pressure thermoelectric and structural property measurements, density functional theory calculations on the half-Heusler material TiNiSn, and an increase of 15% in the relative dimensionless figure of merit, ZT, around 3 GPa. Thermal and electrical properties were measured utilizing a specialized sample cell assembly designed for the Paris-Edinburgh large-volume press to a maximum pressure of 3.5 GPa. High-pressure structural measurements performed up to 50 GPa in a diamond-anvil cell indicated the emergence of a new high-pressure phase around 20 GPa. A first-principles structure search performed using an ab initio random structure search approach identified the high-pressure phase as an orthorhombic type, in good agreement with the experimental results.
Disciplines
Physical Chemistry
Language
English
Repository Citation
Baker, J.,
Park, C.,
Kenney-Benson, C.,
Sharma, V.,
Kanchana, V.,
Vaitheeswaran, G.,
Pickard, C.,
Cornelius, A.,
Velisavljevic, N.,
Kumar, R.
(2021).
Pressure-Induced Enhancement of Thermoelectric Figure of Merit and Structural Phase Transition in TiNiSn.
Journal of Physical Chemistry Letters
1046-1051.
http://dx.doi.org/10.1021/acs.jpclett.0c03609