About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
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Alloys and Compounds for Thermoelectric and Solar Cell Applications XII
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Presentation Title |
Thermal Conductivity Reduction and Thermoelectric Performance Enhancement of SrTiO3 by Hydride Anion Substitution |
Author(s) |
Xinyi He, Seiya Nomoto, Takayoshi Katase, Terumasa Tadano, Toshio Kamiya |
On-Site Speaker (Planned) |
Xinyi He |
Abstract Scope |
Developing high-efficiency and eco-friendly thermoelectric materials has been a significant challenge. Conventional thermometric materials rely on heavy (toxic) elements to reduce lattice thermal conductivity (κlat). In this study, we demonstrated that hydride anion (H−) substitution effectively suppresses κlat and enhances the thermometric performance (ZT) of SrTiO3 without utilizing heavy elements. We experimentally clarified that H− substitution significantly suppresses κlat from 8.2 W/(mK) of SrTiO3 to 3.6 W/(mK) of SrTiO3-xHx bulk polycrystals with x = 0.216. Consequently, the SrTiO3-xHx polycrystals exhibit a maximum ZT value of 0.11 at room temperature, which further increases to 0.22 at T = 657 K. Theoretical calculations elucidated that H− substitution leads to a mixture of strong Ti-O bonds and weak Ti-H bonds, resulting in the enhanced phonon scattering through the randomly distributed Ti-(O,H) bonds. The H− substitution idea offers a novel approach for ZT enhancement in thermoelectric oxides without utilizing heavy elements. |
Proceedings Inclusion? |
Planned: |
Keywords |
Energy Conversion and Storage, |