摘要
Zintl相化合物因为其独特的晶体结构和优异的输运性能,在能源存储及转换领域尤其是热电材料应用中受到广泛关注.为了理解Zintl相化合物优异热电性能起源,科研工作者们利用中子散射技术结合分子动力学模拟,对晶格热导和电声耦合效应展开研究,取得了一系列成果.本文系统总结了中子散射对一些Zintl相化合物的结构及其晶格动力学的相关研究工作,按照零维A_(14)MPn_(11)型化合物、一维链状化合物、二维层状AB2X2型化合物和其结构变体AB_(4)X_(3)型化合物,层状ZrBeSi结构Zintl相化合物的顺序依次梳理了其低晶格热导率的物理起源.通过中子衍射技术探讨了晶体结构、原子位移参数等信息;围绕中子非弹性散射实验,探讨了声子态密度的测量方法及其对Zintl相化合物动力学性质的研究.在深入认识Zintl相化合物的同时,揭示了其微观结构和优化材料性能,以期对设计新型热电功能材料具有一些启发.
Due to the unique crystal structures and excellent transport properties,the Zintl phase thermoelectric materials have aroused extensive interest in energy storage and conversion.To explore the origins of those excellent performances,a series of experimental and theoretical techniques have been applied,such as neutron scattering,thermal conductivity,and molecular dynamics simulations with machine learning.In this paper,the progress of neutron scattering research on the structure and dynamics of Zintl phase is summarized,for example A_(14)MPn_(11) compounds with zero-dimensional(0D)substructures,1D chains-based compounds,2D layered A2BX2 compounds(including the binary Mg_(3)Sb_(2))and their structural variants,as well as AB_(4)X_(3),and ZrBeSi-type compounds.The underlying mechanisms of intrinsically low lattice thermal conductivity in those Zintl phase are discussed in detail.These compounds generally exhibit the following characteristics:1)strong anharmonicity,which is characterized by strong atomic vibrations and anharmonic phonon-phonon scattering;2)weak chemical bonding,which usually leads to low sound velocity and interatomic force constants,and corresponding to low-energy phonon branches;3)intrinsic vacancy defect,which weakens the bond strengths,softens the lattice,and enhances anharmonic phonon-phonon scattering.Neutron diffraction is applied to studying crystal structures,lattice parameters,atomic occupancies,and atomic displacement parameters.Inelastic neutron scattering measures the lattice dynamics,and density of states,which are related to lattice thermal conductivity.Hence,the physical mechanisms of Zintl compounds are analyzed for optimizing material properties and designing new functional materials.
作者
张翠萍
朱金峰
沈晓玲
舒明方
任清勇
马杰
ZHANG Cuiping;ZHU Jinfeng;SHEN Xiaoling;SHU Mingfang;REN Qingyong;MA Jie(School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China;Spallation Neutron Source Science Center,Dongguan 523803,China;Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;Guangdong Provincial Key Laboratory of Extreme Conditions,Dongguan 523803,China)
出处
《物理学报》
北大核心
2025年第1期41-62,共22页
Acta Physica Sinica
基金
国家重点研发基金(批准号:2022YFA1402702)
国家自然科学基金(批准号:U2032213,12474024)
广东省极端条件重点实验室(批准号:2023B1212010002)
广东省自然科学基金(批准号:2021B1515140014)资助的课题.
关键词
热电效应
Zintl相合金
晶格热导率
中子散射
thermoelectric effect
Zintl phase alloy
lattice thermal conductivity
neutron scattering
