Mg3Sb2基材料具有组成元素蕴藏丰富、无污染、低成本及较高热电性能等优点。然而，较低的载流子迁移率制约着该材料体系热电性能的进一步优化。载流子迁移率与载流子有效质量及能带态密度密切相关。研究发现，Pb掺杂极可能对Mg3Sb2的价带态密度产生有利的影响。据此，本项目拟开展以下研究：a.在DFT框架下进行Mg3Sb2-xPb/Snx能带结构的理论计算；b.采用固相反应法结合SPS制备Mg3Sb2-xPb/Snx化合物，并对其进行组成、微结构表征和热电性能测试；c.探讨Pb/Sn掺杂对Mg3Sb2材料载流子浓度的调控作用；d.分析Pb/Sn掺杂对Mg3Sb2价带态密度、载流子有效质量、载流子迁移率等热电性能的影响规律；e.阐明价带态密度与载流子有效质量、载流子迁移率之间的关系，及其对热电性能的影响机制。本项目旨在优化p型Mg3Sb2的热电性能，同时提出通过调控能带态密度来优化热电性能的新途径。

With the advantages of abundant constituent elements, benign to environment and low cost, Mg3Sb2 based compounds are considered as a kind of potential thermoelectric materials. However, the intrinsic low carrier mobility of Mg3Sb2 materials severely hinders the optimization of thermoelectric performance thereof. Normally, carrier mobility is closely related to the carrier effective mass and band density of states (DOS). Besides, Pb doping could probably affect density of states of valence band of Mg3Sb2 in favor of the high carrier mobility. In this research, the theoretical calculation about the band structure of Mg3Sb2-x(Pb/Sn)x compounds will be performed within the framework of DFT. Mg3Sb2-x(Pb/Sn)x compounds with different Pb/Sn content will be prepared by solid state reaction combined with SPS. Subsequently, the characterization of phase, composition and microstructure as well as the measurements of thermoelectric properties will be conducted for the samples. Moreover, the effect of Pb/Sb doping on carrier concentration, DOS, effective mass and carrier mobility as well as thermoelectric properties will be investigated, respectively. The relations between DOS of valence band and carrier effective mass along with carrier mobility will be clarified. And the action mechanism of DOS to modify thermoelectric properties will be illuminated. This project aims to improve the thermoelectric performance of p-type Mg3Sb2 compound and propose that tuning DOS can serve as an effective method to optimize thermoelectric properties.