高性能新型Mg_(3)(Sb,Bi)_(2)基热电材料的发展现状  

Development of High Performance Mg_(3)(Sb,Bi)_(2)-based Thermoelectric Materials

作　　者：徐晨辉 孔栋 况志祥 陈卓 马燕[1,2] 邹富祥 陈昕 胡晓明 冯波 樊希安[1,2] XU Chenhui;KONG Dong;KUANG Zhixiang;CHEN Zhuo;MA Yan;ZOU Fuxiang;CHEN Xin;HU Xiaoming;FENG Bo;FAN Xi’an(Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,China;The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,武汉430081 [2]武汉科技大学省部共建耐火材料与冶金国家重点实验室,武汉430081

出　　处：《材料导报》2023年第13期9-18,共10页Materials Reports

基　　金：湖北省支持企业技术创新发展项目(QYJSCX2021000321);国家重点研发计划(SQ2020YFF0404755);湖北省“双创战略团队”项目(CYTDC2018000094);鄂州市科技计划项目(EZ01-001-20190001);湖北省自然科学基金青年项目(2021CFB009)。

摘　　要：热电材料能够实现热能与电能的相互转换,是一种可以应用于余热回收及半导体制冷等相关领域的功能性材料。传统热电材料的发展目前已趋于成熟,但仍然面临着高昂的原料成本及较低的热电转换效率等问题。Mg_(3)(Sb,Bi)_(2)基热电材料自被发现以来就以其低成本的元素组成和作为Zintl相具备的本征低热导率受到广泛关注。其中n型传导样品由于高能带简并度的优势更是有着较高的塞贝克系数,相较于传统中低温热电材料具备更大的发展潜力。然而,较大的带隙使得Mg_(3)(Sb,Bi)_(2)基热电材料载流子浓度整体偏低,同时还存在着由Mg空位引起的热稳定性较差的问题。为此,在保证该材料低热导率的同时,研究者们尝试了不同的制备工艺,并通过组分优化和结构优化来不断改善其电输运性能及热稳定性。目前Mg_(3)(Sb,Bi)_(2)基热电材料的最大ZT值已经达到1.8以上,同时其器件化后的热电转换效率也可媲美于传统Bi_(2)Te_(3)基热电器件。本文总结了Mg_(3)(Sb,Bi)_(2)基热电材料的基础物理性能与制备方法,从不同的优化手段出发依次介绍了现阶段该材料的研究成果,并展望了其在未来可行的发展方向。Thermoelectric materials that convert electric energy and thermal energy are applied as functional materials in waste heat recovery and semiconductor refrigeration.Research on conventional thermoelectric materials has reached maturity;further development of such materials is hampered by the high cost of raw materials and low thermoelectric conversion efficiency.To overcome these limitations,Mg_(3)(Sb,Bi)_(2)Zintl phases have attracted extensive attention since their discovery and have been widely applied as thermoelectric materials because of their low cost and intrinsic low thermal conductivity.In addition,N-type Mg_(3)(Sb,Bi)_(2)-based conduction materials,having a high Seebeck coefficient owing to high energy band degeneracy,are hypothesized to be more effective than conventional medium-and low-temperature thermoelectric materials.However,the application of Mg_(3)(Sb,Bi)_(2)-based thermoelectric materials is limited because of the low carrier concentration caused by the large bandgap and the low thermal stability due to Mg vacancies.In addition to the maintenance of initial low thermal conductivity of such materials,researchers have continually tried to improve the electrical transport performance and thermal stability by employing different preparation processes and by conducting component and structure optimization.At present,the maximum ZT value of Mg_(3)(Sb,Bi)_(2)-based thermoelectric materials is above 1.8,and the conversion efficiency of the Mg_(3)(Sb,Bi)_(2)-based thermoelectric devices has been comparable to that of conventional low-temperature thermoelectric materials.This paper summarizes the physical properties and preparation methods of Mg_(3)(Sb,Bi)_(2)-based thermoelectric materials.The research progress on different optimization methods to prepare Mg_(3)(Sb,Bi)_(2)-based thermoelectric materials is discussed in detail,and possible future developments of the materials are presented.

关 键 词：热电材料 镁合金 Mg_(3)(Sb Bi)_(2) 热电性能优化 

分 类 号：TB34[一般工业技术—材料科学与工程]