1. Pressure-Induced Enhancement of Thermoelectric Figure of Merit and Structural Phase Transition in TiNiSn
- Author
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Baker, Jason L, Park, Changyong, Kenney-Benson, Curtis, Sharma, Vineet Kumar, Kanchana, V, Vaitheeswaran, G, Pickard, Chris J, Cornelius, Andrew, Velisavljevic, Nenad, Kumar, Ravhi S, Park, Changyong [0000-0002-3363-5788], Vaitheeswaran, G [0000-0002-2320-7667], Kumar, Ravhi S [0000-0002-1967-1619], and Apollo - University of Cambridge Repository
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3403 Macromolecular and Materials Chemistry ,34 Chemical Sciences ,51 Physical Sciences - Abstract
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.
- Published
- 2021
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