Point Defect Engineering of High-Performance Bismuth-Telluride-Based Thermoelectric Materials
Point Defect Engineering of High-Performance Bismuth-Telluride-Based Thermoelectric Materials
复制标题
高性能碲化铋基热电材料的点缺陷工程
DOI：
10.1002/adfm.201400474
复制
发表时间：
2014-09-01
影响因子：
19
通讯作者：
Zhao, Xinbing
中科院分区：
文献类型：
--
作者：
Hu, Lipeng;Zhu, Tiejun;Zhao, Xinbing
开发高性能的热电材料是实现热能直接转换为电能的关键之一。本文介绍了原子尺度点缺陷工程作为同时优化热电材料电学性能和晶格热导率的新策略，并选择（Bi，Sb）（2）（Te，Se）（3）热电固溶体作为范例来证明这种新方法的适用性。本征点缺陷在提高热电性能中起着重要作用。通过调节点缺陷的形成能和热变形，在该系统中设计了反位缺陷和类施主效应。结果，对于n型多晶Bi_2 Te_（2.3）Se_（0.7）合金，在445 K下获得了接近1.2的品质因数ZT的记录值，对于p型多晶Bi-0.3 Sb_（1.7）Te_（3）合金，在380 K下获得了接近1.3的高ZT值，这两个值都高于商业区熔锭的值。这些结果表明，点缺陷工程作为一种新的策略，以优化热电性能的承诺。
Developing high-performance thermoelectric materials is one of the crucial aspects for direct thermal-to-electric energy conversion. Herein, atomic scale point defect engineering is introduced as a new strategy to simultaneously optimize the electrical properties and lattice thermal conductivity of thermoelectric materials, and (Bi,Sb)(2)(Te,Se)(3) thermoelectric solid solutions are selected as a paradigm to demonstrate the applicability of this new approach. Intrinsic point defects play an important role in enhancing the thermoelectric properties. Antisite defects and donor-like effects are engineered in this system by tuning the formation energy of point defects and hot deformation. As a result, a record value of the figure of merit ZT of approximate to 1.2 at 445 K is obtained for n-type polycrystalline Bi2Te2.3Se0.7 alloys, and a high ZT value of approximate to 1.3 at 380 K is achieved for p-type polycrystalline Bi-0.3 Sb1.7Te3 alloys, both values being higher than those of commercial zone-melted ingots. These results demonstrate the promise of point defect engineering as a new strategy to optimize thermoelectric properties.