Ultralow Lattice Thermal Conductivity and Large Glass-Like Contribution in Cs₃Bi₂I₆Cl₃: Rattling Atoms and p-Band Electrons Driven Dynamic Rotation.

ABSTRACT: Understanding the origin of ultralow lattice thermal conductivity κ_L of halide perovskites is of great significance in the energy conversion field. The soft phonon modes and the large anharmonicity corresponding to the dynamic rotation of halogen atoms play an important role in limiting the thermal transport of halide perovskites. The dynamic rotation has long been thought to originate from the electrostatic repulsion of lone pairs around halogen atoms. Here, by studying the layered perovskite Cs₃Bi₂I₆Cl₃, it is found that the interaction between the lone pairs contributed by the s bands of halogen atoms is short-range, and the dynamic rotation is really driven by the occupied p-band electrons. It dominates Cs₃Bi₂

SUBMITTER: Wu Y 

PROVIDER: S-EPMC11558099 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature