Jia Kang, Yang Chuan-Lu, Wang Mei-Shan, Ma Xiao-Guang, Yi You-Gen
School of Physics and Optoelectronics Engineering, Ludong University, Yantai 26425, People's Republic of China.
Hunan Key Laboratory for High -Microstructure and Ultrafast Process, College of Physics and Electronics, Central South University, Changsha 410083, People's Republic of China.
J Phys Condens Matter. 2021 Mar 3;33(9):095501. doi: 10.1088/1361-648X/abcbdc.
The remarkable thermoelectric performance is predicted for half-Heusler (HH) compounds of CuLiX (X = Se, Te) based on the first-principles calculation, the deformation potential (DP) theory, and semi-classical Boltzmann theory. The Slack model is employed to evaluate the lattice thermal conductivity and the result is in good agreement with the previously reported data. The results of mechanical properties demonstrate that CuLiSe is ductile but CuLiTe is brittle. The relaxation time and the carrier mobility are calculated with DP theory. The electrical and thermal conductivities are obtained by using the semi-classical Boltzmann theory based on the relaxation approximation. The Seebeck coefficient and power factor are obtained and their characters are analyzed. The dimensionless figure of merits (ZT) is obtained for the p- and n-type CuLiX. The maximum ZT of 2.65 can be achieved for n-type CuLiTe at the carrier concentration of 3.19 × 10 cm and 900 K, which indicates that this compound is a very promising candidate for the highly efficient thermoelectric materials.
基于第一性原理计算、形变势（DP）理论和半经典玻尔兹曼理论，预测了CuLiX（X = Se，Te）的半赫斯勒（HH）化合物具有卓越的热电性能。采用斯莱克模型评估晶格热导率，结果与先前报道的数据吻合良好。力学性能结果表明，CuLiSe具有延展性，而CuLiTe是脆性的。利用DP理论计算弛豫时间和载流子迁移率。基于弛豫近似，采用半经典玻尔兹曼理论获得电导率和热导率。获得塞贝克系数和功率因子并分析其特性。得到了p型和n型CuLiX的无量纲优值（ZT）。对于n型CuLiTe，在载流子浓度为3.19×10 cm和900 K时，最大ZT可达2.65，这表明该化合物是高效热电材料的极具潜力的候选者。
