Decoupling of thermoelectric transport performance of Ag doped and Se alloyed tellurium induced by carrier mobility compensation  

作　　者：Yue Wu Xiaofan Zhang Boyi Wang Jingxuan Liang Zipei Zhang Jiawei Yang Ximeng Dong Shuqi Zheng Huai-zhou Zhao 

机构地区：[1]State Key Laboratory of Heavy Oil Processing,College of New Energy and Materials,China University of Petroleum,Beijing 102249,China [2]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Journal of Materials Science & Technology》2022年第6期71-79,共9页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (No. 51871240)。

摘　　要：Alloying with Se is proved to be feasible to suppress the lattice thermal conductivity(κL)of tellurium by introducing multidimensional lattice defects.However,extra ionization impurity centers induced by Se alloying are harmful to the electric transport properties of the matrix.In this paper,we propose that the incorporation of Ag could successfully compensate the lost carrier mobility(μH)due to Se alloying through the regulation of microstructure,resulting in the higher power factor(PF)than that of samples without Ag.After composition optimization,theκLdecreased from 1.29 W m^(-1)K^(-1) of Te_(0.99)Sb_(0.01) to 1.05 W m^(-1)K^(-1) of Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01) at 350 K,while the PF remained unchanged or even slightly increased.Benefit from the synergistic effect of carrier mobility compensation and phonon scattering,a maximum z T of 0.91 at 573 K and an average z T of 0.57(between 298 and 573 K)are achieved in Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01).This work presents a new strategy for decoupling the thermal and electric parameters of Te-based thermoelectric materials.

关 键 词：TE Ag doping Microstructure regulation Mobility compensation 

分 类 号：TQ125.3[化学工程—无机化工] TB34[一般工业技术—材料科学与工程]