Thermoelectricity is a potential energy conversion technology due to its ability of converting the ther-mal energy into the electric energy. Although the thermoelectric devices are stable and simple,low efficiency limits its applications. Therefore,the method of improving the thermoelectric performance is a hot topic." Phonon-glass electron-crystal" with high electronic conductivity and low thermal conductivity is recognized as a solution of designing perfect thermoelectric materials. There are two suggestions of enhancing the thermoelec-tric efficiency:Tailoring the band structure and reducing the lattice thermal conductivity,such as dopingpoint defects and heavy mass,designing complex crystal structures and strong anharmonicity of chemical bond,in-troducing rattling atoms,and so on. Those methods will affect thephonon properties. Neutron scattering tech-nique,such as elastic neutron diffraction,inelastic neutron scattering and neutron diffuse scattering,can be used to study the crystal structures,lattice parameters,atomic occupancies,mean-square-displacements,lat-tice strains,phonon dispersion relation and density-of-state,which interfere the thermal conductivities. There-fore,neutron scattering plays an important role in studying the thermoelectric materials.%热电材料是一种可以直接将热能转换为电能的有效能源材料,具有较高稳定性及简单结构等特点,但是低的能效限制了它的应用.因此,如何有效提高热电材料的效率是当下一个研究热点."声子玻璃-电子晶体"(即高电导率低热导率材料)概念为设计理想的热电材料提供了一个明确的思路:目前,剪裁能带结构和降低晶格热导是改善热电性能的两个主流方向.其中降低晶格热导的方法主要集中在微观上改变声子色散关系,包括掺杂点缺陷和重原子、构造复杂的晶体结构和衍生非简谐性原子键、引入ratteling原子等等.中子散射技术(包括中子衍射、非弹性中子散射、中子漫散射等技术)可以从晶体结构、原子占位、均方位移、结构内应力、声子色散关系与态密度等多方面研究与晶格热导率相关的微观机制,在热电材料的研究中起着重要的作用.
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