Effect of Halogen Ions on the Low Thermal Conductivity of Cesium Halide Perovskite

Shoya Kawano, Terumasa Tadano, Satoshi Iikubo

Research output: Contribution to journalArticlepeer-review

Abstract

The lattice dynamics of CsSnX3 (X = Cl, Br, and I) and CsPbI3, which are low-thermal-conductivity materials, are investigated using first-principles phonon calculations. Because of the strong lattice anharmonicity and the accompanying instability of high-temperature cubic phases, the self-consistent phonon theory, which can incorporate the effect of lattice anharmonicity at a mean-field level, is applied in this study. The calculated lattice thermal conductivity reproduced a low thermal conductivity, as shown experimentally, owing to the short phonon lifetime due to the incoherent scattering contribution of Cs atoms. The halogen ion dependence on thermal conductivity reveals that CsSnCl3 exhibits an anomalous lattice thermal conductivity that is as low as that of CsSnBr3. This indicates that the lattice dynamics cannot be explained merely in terms of the atomic mass of the compounds. The low thermal conductivity of CsSnCl3 is caused by the exceptionally short phonon lifetime; further, a bonding analysis suggests that covalent bonding contributes significantly to the unusual anharmonicity of CsSnCl3.

Original languageEnglish
Pages (from-to)91-97
Number of pages7
JournalJournal of Physical Chemistry C
Volume125
Issue number1
DOIs
Publication statusPublished - Jan 14 2021
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films

Fingerprint Dive into the research topics of 'Effect of Halogen Ions on the Low Thermal Conductivity of Cesium Halide Perovskite'. Together they form a unique fingerprint.

Cite this