Metallization and Diffusion Bonding of CoSb3-Based Thermoelectric Materials
Metallization and Diffusion Bonding of CoSb3-Based Thermoelectric Materials
复制标题
CoSb3基热电材料的金属化和扩散连接
DOI：
10.3390/ma13051130
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发表时间：
2020-03-01
期刊：
影响因子：
3.4
通讯作者：
Feng, Jicai
中科院分区：
文献类型：
--
作者：
Feng, Hangbin;Zhang, Lixia;Feng, Jicai
CoSb 3基方钴矿合金是中温区（室温-550 ℃）最有前途的热电材料之一。然而，直接在烧结方钴矿颗粒上实现适当的金属化层对于真实的热电发电应用是必不可少的。在这里，我们报告的方法来制备金属化层和随后的扩散连接方法的高性能的多填充n型方钴矿合金。采用电镀结合低温退火的方法，成功地在方钴矿合金表面制备了Co-Mo金属化层。通过改变镀层的化学组成，优化了镀层的热膨胀系数，该系数可由电镀温度、电流和溶液中Mo离子的浓度来控制。然后，我们使用在600摄氏度和1 MPa下进行10分钟的扩散接合方法将金属化的方钴矿腿接合到Cu-Mo电极。Co-Mo/方钴矿界面表现出极低的比接触电阻率，为1.41 μ ohm cm（2）。金属化层在550 ℃退火60 h后，抑制元素互扩散至小于11 μ m，表明具有良好的热稳定性。目前的研究结果为大规模制备CoSb 3基热电模块铺平了道路。
CoSb3-based skutterudite alloy is one of the most promising thermoelectric materials in the middle temperature range (room temperature-550 degrees C). However, the realization of an appropriate metallization layer directly on the sintered skutterudite pellet is indispensable for the real thermoelectric generation application. Here, we report an approach to prepare the metallization layer and the subsequent diffusion bonding method for the high-performance multi-filled n-type skutterudite alloys. Using the electroplating followed by low-temperature annealing approaches, we successfully fabricated a Co-Mo metallization layer on the surface of the skutterudite alloy. The coefficient of thermal expansion of the electroplated layer was optimized by changing its chemical composition, which can be controlled by the electroplating temperature, current and the concentration of the Mo ions in the solution. We then joined the metallized skutterudite leg to the Cu-Mo electrode using a diffusion bonding method performed at 600 degrees C and 1 MPa for 10 min. The Co-Mo/skutterudite interfaces exhibit extremely low specific contact resistivity of 1.41 mu ohm cm(2). The metallization layer inhibited the elemental inter-diffusion to less than 11 mu m after annealing at 550 degrees C for 60 h, indicating a good thermal stability. The current results pave the way for the large-scale fabrication of CoSb3-based thermoelectric modules.