Ultralow Lattice Thermal Conductivity in Ba23M10Ge10Sb25‑δ (M = Ga, In): Quaternary Compounds Containing Ba-Centered Dodecahedra
Ultralow Lattice Thermal Conductivity in Ba23M10Ge10Sb25‑δ (M = Ga, In): Quaternary Compounds Containing Ba-Centered Dodecahedra
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Ba23M10Ge10Sb25-delta (M = Ga, In) 中的超低晶格热导率：含有 Ba 中心十二面体的四元化合物
DOI：
10.1021/acs.chemmater.8b01441
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发表时间：
2018
影响因子：
8.6
通讯作者：
Xia Sheng-Qing
中科院分区：
文献类型：
--
作者：
Pan Ming-Yan;Qi Hong-Ji;Liu Xiao-Cun;Bai Ming-Cheng;Xia Sheng-Qing
利用高温固相反应合成了ba23ga10ge10sb25和Ba23In10Ge10Sb24.79两个新的季元化合物。这些新相表现出巨大的单位细胞（分别为V= 17 514.6和18 455.8 Å3for含Ga和含in化合物），由544个原子组成，并具有通过Sb-Sb键连接的“洋葱状”m20ge20sb30簇。在这些簇中，大量孤立的单元，如Ba、Sb或sb3三聚体被填充。由于Ba23Ga10Ge10Sb25具有如此复杂的结构，且具有较大的单体胞和大量的重原子组成，因此在323 ~ 823 K范围内，其晶格导热系数（κl）在0.2 ~ 0.38 W·m-1·K - 1之间。结果，在823 K时达到了最大zt0.27。
Two new quaternary compounds, Ba23Ga10Ge10Sb25and Ba23In10Ge10Sb24.79, have been synthesized by using the high temperature solid-state reactions. These new phases exhibit huge unit cells (V= 17 514.6 and 18 455.8 Å3for Ga- and In-containing compounds, respectively),which comprise 544 atoms and feature “onion-like” M20Ge20Sb30clusters connected through the Sb–Sb bonds. Among these clusters, substantial isolated units such as Ba, Sb, or Sb3trimers are filled. With such a complex structure as well as the large unit cell and substantial heavy constituent atoms, ultralow lattice thermal conductivity (κl) was observed for Ba23Ga10Ge10Sb25, ranging from 0.2 to 0.38 W·m–1·K–1from 323 to 823 K. As a result, a maximunZTof 0.27 was achieved at 823 K.