复杂结构Zintl相因为具有“电子晶体、声子玻璃”特征，是一类非常具有开发前景的热电材料。近年来，环境友好型n型Te掺杂的Mg3Sb2基（CaAl2Si2结构）Zintl材料性能突出而被广泛关注，其性能可与传统热电材料相媲美。但是，同种结构的p型Zintl性能却相对较低，而要搭建高性能热电器件需要性能相匹配的p型材料。本项目的研究目标是制备与n型材料相匹配性能的环境友好型p型Bi基Zintl，项目的研究思路包括:1）拟采用微观组织结构调控如单晶制备、择优取向织构、晶粒尺寸控制等方法调节载流子迁移率和电性能；2）运用缺陷工程调控优化载流子浓度；3）运用能带工程调控及固溶方法结合理论计算寻找合适的掺杂取代元素实现电和声的协同调控。本项目成果有望为制备p型Zintl探索构筑合适的方法，加深此体系中电传输和热传输耦合调控手段的认知，为此类Zintl的未来应用奠定理论和实验上的基础。

Complex Zintl phases are good candidates as thermoelectric materials because of their intrinsic “electron–crystal, phonon–glass” nature. Recently, environmental-friendly n-type Te doped Mg3Sb2-based (CaAl2Si2-structured) Zintl phase has been extensively investigated due to its very good thermoelectric performance, which can be comparable to some typically conventional thermoelectric materials. However, the thermoelectric properties of this p-type Zintl materials sharing the same structures are relatively low. To construct a high-performance thermoelectric device, it is required to develop both performance-matched n-type and p-type materials. This project will confuse on optimizing the thermoelectric properties of environmental-friendly p-type Bi-based Zintl phases, and the design strategies for developing high performance p-type Zintl phase will include 1) approaches of microstructures modification such as single-crystal growth, texturing, controlled grain size to further enhance the carrier mobility and electrical conductivity; 2) defects engineering to optimize the carrier concentrations; 3) solid solution methods and band engineering to allow electrical and thermal transport behavior adjusted at the same time. Generally, this project is expected to explore an optimized fabrication method of p-type Zintls, deepen the understanding of mechanism of adjusting both electrical and thermal transport properties, and provide theoretical and technical supports for laying the foundation of future application for the Zintl thermoelectric materials.