Crystal chemistry in phase change thermoelectrics

相变热电晶体化学

• 批准号: 398512982
• 负责人: Professor Dr. Wolfgang Zeier
• 金额: --
• 依托单位: Institut für Anorganische und Analytische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/398512982?language=en
• 关键词: Crystal; chemistry; phase; change; thermoelectrics

Thermoelectric materials convert thermal in electrical energy and provide the possibility to recover waste heat in industrial processes. However, the underlying crystal chemical influences on thermoelectric transport is still not fully understood. Novel approaches for improved thermoelectric transport focus on the engineering of the band structure to achieve band convergence and high band degeneracy. Just recently, it was shown that a high crystal symmetry leads to a high number in the band degeneracy. The hypothesis of this proposal is based on the current understanding that a more cubic lattice will lead to better thermoelectric transport. Phase change materials exhibit good thermoelectric transport in their cubic high temperature structures and are ideal candidates for understanding the effects of crystal symmetry on the transport. Using crystal chemical approaches the phase changes will be altered, and the structural symmetry controlled. This proposal seeks a better fundamental understanding of how elemental substitution can shift or suppress phase changes and stabilize high temperature crystal structures at lower temperatures. The resulting effect on the thermoelectric transport will be explored.

热电材料将热能转化为电能，并提供了在工业过程中回收废热的可能性。然而，潜在的晶体化学对热电输运的影响仍然没有完全理解。改善热电输运的新方法集中在能带结构的工程上，以实现能带收敛和高能带简并。就在最近，它表明，一个高的晶体对称性导致一个高的数字在带简并。该提议的假设是基于目前的理解，即更多的立方晶格将导致更好的热电输运。相变材料在其立方高温结构中表现出良好的热电输运，并且是理解晶体对称性对输运的影响的理想候选者。利用晶体化学方法可以改变相变，控制结构对称性。该提案旨在更好地从根本上理解元素取代如何在较低温度下改变或抑制相变并稳定高温晶体结构。将探讨由此产生的热电运输的影响。

项目成果

Origin of Ultralow Thermal Conductivity in n-Type Cubic Bulk AgBiS2: Soft Ag Vibrations and Local Structural Distortion Induced by the Bi 6s2 Lone Pair

• DOI: 10.1021/acs.chemmater.9b00001
• 发表时间: 2019-03
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Ekashmi Rathore;R. Juneja;Sean P. Culver;Nicoló Minafra;A. Singh;W. Zeier;K. Biswas