Te基热电器件反常界面层生长行为及界面稳定性研究OA北大核心CSTPCD
Interface Layer of Te-based Thermoelectric Device:Abnormal Growth and Interface Stability
单质Te具有优异的热电优值(ZT),但其与金属电极连接界面处的剧烈元素交互扩散及反应会引入较大的接触电阻率(ρc),导致器件的转换效率(η)较低.因此,寻找合适的阻挡层来优化Te与金属电极间的连接至关重要.本研究基于梯度结构报道了一种宽相场Ni-Te合金阻挡层NiTe2-m(NixTe(x=0.500～0.908)).结果表明,当x=0.500 时,Ni0.5Te/Te0.985Sb0.015/Ni0.5Te器件的界面处无任何反应层及微观缺陷,ρc小于10 μΩ·cm2,η在180 K温差(热端温度473 K)时达到了理论值的75%.同时,界面具有良好的热稳定性,在473 K老化期间,界面微观组织、ρc以及η无明显变化.当x>0.500 时,界面反应层厚度随x增大而逐渐减小,即主导界面反应层生长行为的因素并非常规的界面反应能及浓度梯度等热力学因素.进一步分析表明,反常生长源于动力学因素中的"原子空位"对反应层生成的迟滞作用.
Though Te has excellent figure of merit(ZT),the severe element diffusion and reaction at the Te/metallic-electrodes interface render high contact resistivity(ρc)and low device conversion efficiency(η).Therefore,it is critical to develop suitable barrier layers for optimizing the bonding between Te and metallic electrodes.In this work,an appropriate barrier layer,NiTe2-m(NixTe(x=0.500～0.908)),was screened based on gradient structure.No reaction layers and defects at the interface of Ni0.5Te/Te0.985Sb0.015/Ni0.5Te were detected before and after aging at 473 K.Low ρc(less than 10 μΩ·cm2)and high η(about 75%of the theoretical value under a temperature difference of 180 K(hot end:473 K))were achieved and maintained stable during aging,showing excellent thermal stability of the interface.When x>0.500,the thickness of the interface reaction layer decreased with x increasing,showing the retarding effect dominating the growth behavior of interface reaction layer not from the usual thermodynamic factors,such as interface reaction energy and composition gradient,but from the"atom vacancy"on formation of the reaction layer.
苗鑫;闫世强;韦金豆;吴超;樊文浩;陈少平
太原理工大学 材料科学与工程学院,太原 030024太原理工大学 物理学院,太原 030024
电子信息工程
Te热电器件扩散动力学阻挡层热稳定性
Tethermoelectric devicediffusion dynamicbarrierthermal stability
《无机材料学报》 2024 (008)
903-910,中插4-中插7 / 12
国家自然科学基金(52202277);山西省科技合作与交流专项项目(202104041101007);山西省省筹资金资助回国留学人员科研项目(2023-083) National Natural Science Foundation of China(52202277);Special Project of Science and Technology Cooperation and Exchange of Shanxi Province(202104041101007);Shanxi Scholarship Council of China(2023-083)
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