Back to Search
Start Over
Strong anharmonicity and high thermoelectric performance of cubic thallium-based fluoride perovskites TlXF3 (X = Hg, Sn, Pb).
- Source :
- Physical Chemistry Chemical Physics (PCCP); 2/21/2023, Vol. 25 Issue 7, p5776-5784, 9p
- Publication Year :
- 2023
-
Abstract
- State-of-the-art first-principles calculations are performed to investigate the thermoelectric transport properties in thallium-based fluoride perovskites TlXF<subscript>3</subscript> (X = Hg, Sn, Pb) by considering anharmonic renormalization of the phonon energy and capturing reasonable electron relaxation times. The lattice thermal conductivity, κ<subscript>L</subscript>, of the three compounds is very low, among which TlPbF<subscript>3</subscript> is only 0.42 W m<superscript>−1</superscript> K<superscript>−1</superscript> at 300 K, which is less than half of that of quartz glass. The low acoustic mode group velocity and strong three-phonon scattering caused by the strong anharmonicity of the Tl atom are the origin of the ultralow κ<subscript>L</subscript>. Meanwhile, the strong ionic bonds between X (X = Hg, Sn, Pb) and F atoms provide good electrical transport properties. The results show that the ZT value of TlHgF<subscript>3</subscript> at 900 K is 1.58, which is higher than the 1.5 value of FeNbSb at 1200 K. TlSnF<subscript>3</subscript> and TlPbF<subscript>3</subscript> also exceed 1, which is close to the classical thermoelectric material PbTe:Na. Furthermore, we present the methods and expected effects of improving the ZT value through nanostructures. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 14639076
- Volume :
- 25
- Issue :
- 7
- Database :
- Complementary Index
- Journal :
- Physical Chemistry Chemical Physics (PCCP)
- Publication Type :
- Academic Journal
- Accession number :
- 161933123
- Full Text :
- https://doi.org/10.1039/d2cp05382a