Entropy Engineering in Multi-Principal-Element Alloyed SnTe
SEMINAR
The State Key Lab of
High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics, Chinese Academy of Sciences
中 国 科 学 院 上 海 硅 酸 盐 研 究 所 高 性 能 陶 瓷 和 超 微 结 构 国 家 重 点 实 验 室
Entropy Engineering in Multi-Principal-Element Alloyed SnTe
贺 健
美国克莱姆森大学物理及天文系
时间:2019 年 5 月22日(星期三)上午10:00
地点:嘉定园区F楼5(1)会议室
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联系人:史 迅
报告摘要:
Charge flow, entropy flow, and the interplay in between are at the core of many regimes of functional materials research, including thermoelectrics, the simplest technology applicable for direct heat-electricity energy conversion. In the context of high entropy alloys, here we present a systematic synthesis, structural, theoretical and thermoelectric study of multi-principal-element alloyed SnTe. We demonstrated that high entropy of mixing extended the solubility limit of Mn while retaining the lattice symmetry, the enhanced Mn content elicited multiscale microstructures including lattice distortions, strain clusters, intertwined dislocations and nanoprecipitates, resulting in lattice thermal conductivity lower than the amorphous limit. High entropy alloying also altered the carrier scattering mechanism, enhanced band convergence and band effective mass, thereby yielding good power factors at high carrier concentrations. High average zT values were obtained over a wide temperature range. In view of the simple face-centered-cubic structure of SnTe-based alloys, these results attest to the efficacy of entropy engineering towards a new paradigm of high-entropy thermoelectrics.
报告人简介:
贺健博士,1991 年获吉林大学凝聚态物理专业学士,1991-1998年在中国原子能科学研究院从事热中子散射,研究对象为生物大分子和无机分形体系,2004年获美国田纳西大学凝聚态物理专业博士,师从Ward Plummer教授和David Mandrus教授,专业方向为强关联电子体系单晶生长和物性研究。博士后期间开始从事热电研究,师从T.M. Tritt教授。2008年起任克莱姆森大学物理及天文系助理教授,2014年晋升为副教授(终身教职)。现为美国材料研究学会和美国科学促进协会成员,《科学》杂志评审编委会成员。目前主要从事热电材料、超导材料以及低维电子自旋体系的研究。迄今在Science,Nature Physics,Adv. Mater., Phys. Rev. Letters,Phys. Rev. B和Adv. Energy Mater.等学术期刊共发表同行评议文章155篇, 他引4200次,h因子37。多次担任 MCARE,CMPM,TEP-CH,ICT 和MRS春季秋季会议等国际会议的分会主席。并为多个国际著名学术期刊和美国欧洲亚洲多个基金经常性评审。
本次学术报告将以碲化锡为例,内容跨越两大类功能材料:高熵合金和热电材料,意在揭示两者间的内在联系和冲突,初探高熵热电的前景。