Strategy of Extra Zr Doping on the Enhancement of Thermoelectric Performance for TiZrxNiSn Synthesized by a Modified Solid-State Reaction
Strategy of Extra Zr Doping on the Enhancement of Thermoelectric Performance for TiZrxNiSn Synthesized by a Modified Solid-State Reaction
复制标题
额外Zr掺杂增强改进固相反应合成TiZrxNiSn热电性能的策略
DOI：
10.1021/acsami.1c14723
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发表时间：
2021-10-07
影响因子：
9.5
通讯作者：
Peng, Biaolin
中科院分区：
文献类型：
--
作者：
Chen, Jun-Liang;Yang, Hengquan;Peng, Biaolin
Half-Heusler合金具有热稳定性高、功率因数大、力学性能好等优点，在中温热电领域的应用越来越受到人们的关注。在这项工作中，额外的Zr掺杂的TiZrxNiSn样品成功地制备了一个改进的固相反应，然后放电等离子烧结。这表明额外的Zr掺杂不仅可以提高Seebeck系数的原因而提高功率因数，而且还可以抑制由超晶格纳米畴和次级纳米颗粒增强的声子散射引起的晶格热导率。结果表明，TiZr_（0.015）NiSn合金的功率因数提高了3.29 mW m（-1）K_（2-），晶格热导率降低了1.74 W m（-1）K_（2-），峰值ZT在773 K时高达0.88，在373 - 773 K温度范围内平均ZT值高达0.62。本文的工作为通过调整TiNiSn基合金的二次纳米相和超晶格纳米畴的微观结构来优化其热电性能提供了指导。
Half-Heusler alloys, which possess the advantages of high thermal stability, a large power factor, and good mechanical property, have been attracting increasing interest in mid-temperature thermoelectric applications. In this work, extra Zr-doped TiZrxNiSn samples were successfully prepared by a modified solid-state reaction followed by spark plasma sintering. It demonstrates that extra Zr doping could not only improve the power factor on account of an increase in the Seebeck coefficient but also suppress the lattice thermal conductivity originated from the strengthened phonon scattering by the superlattice nanodomains and the secondary nanoparticles. As a consequence, an increased power factor of 3.29 mW m(-1) K--(2) and a decreased lattice thermal conductivity of 1.74 W m(-1) K-1 are achieved in TiZr0.015NiSn, leading to a peak ZT as high as 0.88 at 773 K and an average ZT value up to 0.62 in the temperature range of 373-773 K. This work gives guidance for optimizing the thermoelectric performance of TiNiSn-based alloys by modulating the microstructures on the secondary nanophases and superlattice nanodomains.