开发多元化热电材料一直是科研界关注的焦点，SnTe具有与PbTe相同的立方晶体结构和相似的能带结构，被认为是理想替代PbTe的无铅环保热电材料，应用前景广阔。目前高性能SnTe热电材料主要聚焦在高固溶度掺杂等方面，然而能否在低成本、低固溶度掺杂的情况下实现同等效应SnTe热电性能的提升仍面临较大挑战。鉴于此，本项目基于同步辐射XAFS技术，研究一系列低固溶度(MgTe,MnTe,CdTe等)掺杂SnTe体系的热电性质、局域原子以及电子结构，通过分析不同元素掺杂位点和原子类型，获取各吸收边原子元素价态、空态密度、配位数、原子间距、无序度等参数，从而比较中心与配位原子间的键合模式与强弱。并通过理论计算和物理建模，系统分析SnTe掺杂体系的能带收敛与声子散射类型及传输模式，最终建立局域结构、热电性能、电子-声子输运本征特性之间的内在关联，为设计和开发高效热电材料提供新思路与理论指导。

Developing diversified thermoelectric materials has always been the focus of scientific research. SnTe has the same cubic crystal structure and similar energy band structure as PbTe, which is considered as an ideal lead-free and environment-friendly thermoelectric material to replace PbTe. It has broad application prospects for SnTe materials. Currently, high-performance SnTe thermoelectric materials are mainly focused on high solid-solution-doping, etc. However, it is still a big challenge to realize the improvement of SnTe thermoelectric performance with the same effect under the condition of low cost and low solid-solution-doping. In view of this, this project is based on synchrotron radiation XAFS technology to study the thermoelectric properties, local atomic and electronic structures of a series of low solid-solubility (MgTe, MnTe, CdTe, etc.) doped SnTe systems. By analyzing the doping sites and atomic types of different elements, the parameters of atomic element valence state, empty density of states, coordination number, atomic spacing, disorder degree and the like of each absorption edge will be obtained, so as to compare the bonding mode and strength between the center and coordination atoms. Through theoretical calculation and physical modeling, the band convergence, phonon scattering type and transmission mode of SnTe-doped system will be systematically analyzed. Finally, the intrinsic correlation between local structure, thermoelectric properties and electron-phonon transport intrinsic characteristics is established, which provides new ideas and theoretical guidance for the design and development of high-efficient thermoelectric materials.