Alloy-induced reduction and anisotropy change of lattice thermal conductivity in Ruddlesden–Popper phase halide perovskites  

作　　者：Huimin Mu Kun Zhou Fuyu Tian Yansong Zhou Guoqi Zhao Yuhao Fu Lijun Zhang 

机构地区：[1]State Key Laboratory of Superhard Materials,International Center of Computational Method and Software,College of Physics,Jilin University,Changchun 130012,China [2]State Key Laboratory of Integrated Optoelectronics,Key Laboratory of Automobile Materials of MOE,International Center of Computational Method and Software,College of Materials Science and Engineering,Jilin University,Changchun 130012,China

出　　处：《Frontiers of physics》2023年第6期183-191,共9页物理学前沿（英文版）

基　　金：supported by the National Key Research and Development Program of China (Grant No.2022YFA1402501);the National Natural Science Foundation of China (Grant Nos.12004131,62125402,22090044,and 92061113);Jilin Province Science and Technology Development Program (Grant No.20210508044RQ).

摘　　要：The effective modulation of the thermal conductivity of halide perovskites is of great importance in optimizing their optoelectronic device performance.Based on first-principles lattice dynamics calculations,we found that alloying at the B and X sites can significantly modulate the thermal transport properties of 2D Ruddlesden−Popper(RP)phase halide perovskites,achieving a range of lattice thermal conductivity values from the lowest(κ_(c)=0.05 W·m^(−1)·K^(−1)@Cs_(4)AgBiI_(8))to the highest(κ_(a/b)=0.95 W·m^(−1)·K^(−1)@Cs4NaBiCl_(4)I_(4)).Compared with the pure RP-phase halide perovskites and three-dimensional halide perovskite alloys,the two-dimensional halide perovskite introduces more phonon branches through alloying,resulting in stronger phonon branch coupling,which effectively scatters phonons and reduces thermal conductivity.Alloying can also dramatically regulate the thermal transport anisotropy of RP-phase halide perovskites,with the anisotropy ratio ranging from 1.22 to 4.13.Subsequently,analysis of the phonon transport modes in these structures revealed that the lower phonon velocity and shorter phonon lifetime were the main reasons for their low thermal conductivity.This work further reduces the lattice thermal conductivity of 2D pure RP-phase halide perovskites by alloying methods and provides a strong support for theoretical guidance by gaining insight into the interesting phonon transport phenomena in these compounds.

关 键 词：first-principles lattice dynamics calculations Boltzmann transport all-inorganic RP-phase halide perovskite alloys thermal conductivity 

分 类 号：TG146.23[一般工业技术—材料科学与工程]