高稳定W阻挡层的NbFeSb基半赫斯勒温差发电器件  

NbFeSb-based half-Heusler thermoelectric device with high stable W diffusion barrier layer

作　　者：王雷 宋庆峰 廖锦城[1] 柏胜强[1,2] 陈立东 WANG Lei;SONG Qingfeng;LIAO Jincheng;BAI Shengqiang;CHEN Lidong(State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai,200050,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]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,上海200050 [2]中国科学院大学材料科学与光电技术学院,北京100049

出　　处：《电源技术》2024年第3期519-526,共8页Chinese Journal of Power Sources

基　　金：国家自然科学基金(U2141208,52102330)。

摘　　要：半赫斯勒材料是兼具高性能和高稳定性的中高温热电材料,在深空探测等领域具有重要应用前景。开发了适用于p型Nb_(0.86)Hf_(0.14)FeSb的阻挡层W。通过1073~1173 K的真空等温老化实验,研究了Nb_(0.86)Hf_(0.14)FeSb/W界面的扩散反应行为和电输运性能。扫描电镜能谱分析发现界面发生了扩散反应并生成Fe-W反应层,反应层厚度与老化时间呈抛物线关系,表现为扩散控制过程,扩散激活能为211.1 kJ/mol。界面电阻率测试结果显示老化前后界面电阻率均小于1μΩ·cm^(2)。基于有限元仿真计算结果,制备了以W为阻挡层的NbFeSb基温差发电器件。在温差为744 K时,器件的最大转换效率达9.5%,最大输出功率密度达2.27 W/cm^(2)。Half-Heuslers are the promoted medium-high temperature thermoelectric(TE)materials which have great potential of the application in deep space exploration,based on their high TE performance and high reliability.Tungsten(W)was developed as the diffusion barrier layer for p-type Nb_(0.86)Hf_(0.14)FeSb material.The diffusion/reaction behavior and electric transport performance of Nb_(0.86)Hf_(0.14)FeSb/Winterface were studied under temperatures of 1073~1173 K in vacuum.The Fe-W reaction layer was found at the interface.The thickness of Nb_(0.86)Hf_(0.14)FeSb/W interface with time followed the parabolic rule,indicating that the reactive diffusion behavior of Nb_(0.86)Hf_(0.14)FeSb/W interface was a diffusion-controlled process.The diffusion activation energy was determined as 211.1 kJ/mol.The interface resistivity of Nb_(0.86)Hf_(0.14)FeSb/W was lower than 1μΩ·cm^(2) before and after aging.Based on the optimization result,the NbFeSb-based TE device was fabricated.The maximum conversion efficiency of 9.5%and the output power density of 2.27 W/cm^(2) were realized under temperature difference of 744 K.

关 键 词：温差发电器件 半赫斯勒 界面扩散阻挡层 NbFeSb 

分 类 号：TM913[电气工程—电力电子与电力传动]