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，并为回收工业过程中的废热提供了可能性。然而，晶体化学对热电输运的潜在影响仍未完全了解。改进热电输运的新方法侧重于能带结构的工程设计，以实现能带收敛和高能带简并性。最近，研究表明，高晶体对称性会导致大量能带简并。该提议的假设基于当前的理解，即更多的立方晶格将导致更好的热电传输。相变材料在其立方高温结构中表现出良好的热电输运，是了解晶体对称性对输运影响的理想候选材料。使用晶体化学方法将改变相变，并控制结构对称性。该提案寻求更好地了解元素取代如何改变或抑制相变并在较低温度下稳定高温晶体结构。将探讨由此产生的对热电传输的影响。

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