Yang Xiuxian, Dai Zhenhong, Zhao Yinchang, Liu Jianye, Meng Sheng
Department of Physics, Yantai University, Yantai 264005, People's Republic of China.
J Phys Condens Matter. 2018 Oct 24;30(42):425401. doi: 10.1088/1361-648X/aade17. Epub 2018 Aug 31.
Utilizing the first-principle calculations combined with Boltzmann transport equation and semiclassical analysis, we present a systematic investigation of the electron structure, lattice thermal conductivity [Formula: see text], Seebeck coefficient S, and the dimensionless figure of merit ZT of crystal LiSb and LiBi. The [Formula: see text] of 2.2 and 2.09 W m K are obtained at room temperature in LiSb and LiBi systems with the band gap of [Formula: see text] eV, respectively. The low [Formula: see text] can induce excellent thermoelectric properties. Thus the effect of doping on the transport properties has been judiciously researched and the maximum ZT of 2.42, 1.54 is obtained at 900 K in the p-type doped LiSb and p-type doped LiBi with the stable structures. Up to date, experimental finding of the maximum ZT is 2.6 at 850 K in the CuSe sample with 1 mol indium, our results are very close to this value. This letter provides insight into the thermal transport properties of LiSb and LiBi, meanwhile, supports that crystalline LiSb and LiBi may be promising materials for thermoelectric devices and application.
利用第一性原理计算结合玻尔兹曼输运方程和半经典分析，我们对晶体LiSb和LiBi的电子结构、晶格热导率κ、塞贝克系数S以及无量纲优值ZT进行了系统研究。在室温下，LiSb和LiBi体系的κ分别为2.2和2.09 W m⁻¹ K⁻¹，带隙分别为[具体数值] eV。低κ可诱导出优异的热电性能。因此，我们审慎研究了掺杂对输运性质的影响，在具有稳定结构的p型掺杂LiSb和p型掺杂LiBi中，于900 K时分别获得了2.42和1.54的最大ZT值。截至目前，在含1 mol铟的CuSe样品中，850 K时的实验测得最大ZT为2.6，我们的结果与此值非常接近。这封信深入探讨了LiSb和LiBi的热输运性质，同时表明晶体LiSb和LiBi可能是用于热电装置及应用的有前景的材料。
