Strong quartic anharmonicity,ultralow thermal conductivity,high band degeneracy and good thermoelectric performance in Na_(2)TlSb  

作　　者：Tongcai Yue Yinchang Zhao Jun Ni Sheng Meng Zhenhong Dai 

机构地区：[1]Department of Physics,Yantai University,Yantai 264005,P.R.China [2]Department of Physics,Tsinghua University,Beijing 100084,P.R.China [3]Beijing National Laboratory for Condensed Matter Physics and Institute of Physics,Chinese Academy of Sciences,Beijing 100190,P.R.China [4]Collaborative Innovation Center of Quantum Matter,Beijing 100084,P.R.China

出　　处：《npj Computational Materials》2023年第1期2167-2175,共9页计算材料学（英文）

基　　金：This research were supported by the National Natural Science Foundation of China under Grant No.11974302,No.12174327,No.92270104;the Graduate Innovation Foundation of Yantai University,GIFYTU under Grant No.KGIFYTU2213.

摘　　要：We employ first-principles calculations combined with self-consistent phonon theory and Boltzmann transport equations to investigate the thermal transport and thermoelectric properties of full-Heusler compound Na_(2)TlSb.Our findings exhibit that the strong quartic anharmonicity and temperature dependence of the Tl atom with rattling behavior plays an important role in the lattice stability of Na_(2)TlSb.We find that soft Tl-Sb bonding and resonant bonding in the pseudocage composed of the Na and Sb atoms interaction is responsible for ultralowκL.Meanwhile,the multi-valley band structure increases the band degeneracy,results in a high power factor in p-type Na_(2)TlSb.The coexistence of ultralowκL and high power factor presents that Na_(2)TlSb is a potential candidate for thermoelectric applications.Moreover,these findings help to understand the origin of ultralowκL of full-Heusler compounds with strong quartic anharmonicity,leading to the rational design of full-Heusler compounds with high thermoelectric performance.

关 键 词：HARMONIC BONDING thermal 

分 类 号：TG13[一般工业技术—材料科学与工程]