Enhanced Contact Performance and Thermal Tolerance of Ni/Bi₂Te₃ Joints for Bi₂Te₃-Based Thermoelectric Devices

Abstract

Ni metal has been widely used as a barrier layer in Bi2Te3-based thermoelectric devices, which establishes stable joints to link Bi2Te3-based legs and electrodes. However, the Ni/Bi2Te3 joints become very fragile when the devices were exposed to high temperature, causing severe performance deterioration and even device failure. Herein, stable Ni/Bi2Te3 joints have been established by arc spraying of the Ni barrier layer on the Bi2Te3-based alloys. The interface microstructure and contact performance including the bonding strength and contact resistivity of the arc-sprayed Ni/Bi2Te3 joints are investigated. The results indicate that, as compared with traditional Ni/Bi2Te3 joints, the arc-sprayed Ni/Bi2Te3 joints have comparably low contact resistivity while possessing a 50% higher bonding strength. Aging the joints as an exposure to high-temperature circumstances, the arc-sprayed Ni/Bi2Te3 joints exhibit much better tolerance to the thermal shock with stable bonding strength and contact resistivity. The enhanced interfacial contact performance and thermal tolerance should be attributed to the thick Ni barrier layer and interface reaction layer with good Ohmic contact. This work provides an effective strategy to establish stable joints for the Bi2Te3-based thermoelectric devices with improved thermal stability.

Localized Surface Doping Induced Ultralow Contact Resistance between Metal and (Bi,Sb)2Te3 Thermoelectric Films

“…To date, various technologies for lowing or controlling the contact resistivity of (Bi,Sb) 2 Te 3 and the electrode have been investigated, including surface modification − (orange region), interfacial layer design, ,,, (blue region), and structural modulation ,, (red region) as shown in Figure f. In this work, for both p- and n-type interfaces, ultralow contact resistance is achieved with the localized surface doping strategy, which is basically the best-in-class.…”

Enhanced Electrochemical Performance and Cyclic Stability of Li-Ion Batteries by Employing Nanostructured Bi2Te3 Particles with Amorphous ZrO2 Nanocoating

“…We practiced similar experiments on Bi 2 Te 3 particles before and after annealing at 280 °C for 2 h. Figure b shows the characteristic peaks of bismuth telluride (JCPDS 15–0863), a polycrystalline rhombohedral structure with the main peaks of (221) and (1010) with a c -axis growth orientation preference. Annealing of the powder does not induce major changes except sharpening the diffraction peaks because mechanical milling induces lattice distortion and crystal defects that can be relieved by low-temperature annealing. , The ZrO 2 -treated powder (BTZ-2) also exhibits the same diffraction pattern as the untreated one without evidence of zirconium oxide formation, partly due to the low amount of the added a-ZrO 2 .…”

Recent trends and future perspectives of thermoelectric materials and their applications

“…15a ). 46 Researchers have conducted investigations into the structural parameters, and electronic band structure, as well as the half-metallic and thermoelectric properties of Sr 2 EuReO 6 compound materials (28). Utilizing density-functional calculations within the framework of the generalized gradient approximation the computational analyses reveal a half-metallic nature in the electronic properties.…”