Affiliation:
1. State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Harbin 150001 China
2. Department of Materials Science and Engineering Harbin Institute of Technology Shenzhen 518055 China
3. Science and Technology on Thermal Energy and Power Laboratory Wuhan 430205 China
4. Wuhan Second Ship Design and Research Institute Wuhan 430205 China
Abstract
AbstractMg3(Sb, Bi)2‐based materials possess excellent room‐temperature thermoelectric performance, while poor interfacial behaviors occur when connected with metal electrodes due to the strong chemical activity and volatility of Mg element. In this study, a high efficiency of 7.1% under a temperature difference of 230 K is achieved in n‐Mg3(Sb, Bi)2/p‐Bi2Te3 thermoelectric module. When changing the interfacial layer from Fe powder to Fe foil, it effectively prevents a significant diffusion of both Mg and Bi elements from the material matrix to the interfacial layer, resulting in an extremely low contact resistivity ≈3.4 µΩ cm2 that is almost one order lower than of that of Fe powder/Mg3(Sb, Bi)2 junction ≈30 µΩ cm2. Particularly, a thin diffusion layer with a width of ≈2 µm is initially observed in the unannealed Fe foil/Mg3(Sb, Bi)2 junction. Even after thermal aging at 573 K for 28 days, the diffusion‐layer width is basically unchanged and its corresponding contact resistivity maintained as low as ≈5.8 µΩ cm2. Overall, this work provides deep insights into interfacial design and paves the way for high‐performance and sustainable low‐grade waste heat recovery.
Funder
National Natural Science Foundation of China
Fundamental Research Funds for the Central Universities
Natural Science Foundation of Heilongjiang Province
National Key Research and Development Program of China
Subject
General Materials Science,Renewable Energy, Sustainability and the Environment