Achieving high thermoelectric performance with Pb and Zn codoped polycrystalline SnSe via phase separation and nanostructuring strategies
Achieving high thermoelectric performance with Pb and Zn codoped polycrystalline SnSe via phase separation and nanostructuring strategies
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通过相分离和纳米结构策略实现 Pb 和 Zn 共掺杂多晶 SnSe 的高热电性能
DOI：
10.1016/j.nanoen.2018.09.025
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发表时间：
2018-11-01
期刊：
影响因子：
17.6
通讯作者：
Tang, Guodong
中科院分区：
文献类型：
--
作者：
Liu, Jiang;Wang, Peng;Tang, Guodong
热电技术能够实现热和电之间的直接转换，并可能对热泵和发电机产生重大影响。硒化锡是一种很有前途的热电材料，因为最近在其单晶体中发现了一个很好的热电优值。在多晶SnSe中实现与SnSe单晶的热电性能相当的热电性能仍然具有挑战性。在这里，我们提出了一个新的概念，极低的热导率和高热电性能的多晶SnSe可以通过相分离和纳米结构化策略实现。我们证明，Pb和Zn共掺杂以及PbSe第二相的引入有助于显着提高电导率和功率因数。Sn0.98Pb0.01Zn0.01Se的峰值功率因数达到5.43 μ W cm（-1）K-2。相分离和纳米结构化策略构建了散射声子的全层次结构。通过构造全分层结构和双原子点缺陷散射，晶格热导率显著降低到0.13Wm（-1）K-1。通过提高电输运性能同时保持超低热导率，在多晶SnSe中实现了创纪录的高热电性能ZT = 2.2。这一工作为实现多晶SnSe中高ZT值提供了新的策略。
Thermoelectric technology, enables direct conversion between heat and electricity and may have a significant impact on heat pumps and power generators. SnSe emerges as a promising thermoelectric material since the recent discovery of an ultrahigh thermoelectric figure of merit in its single crystals. It is still challenging to achieve thermoelectric performance comparable to those of the SnSe single crystals in polycrystalline SnSe. Here, we propose a new concept that extremely low thermal conductivity and high thermoelectric performance in polycrystalline SnSe can be achieved via phase separation and nanostructuring strategies. We demonstrate that Pb and Zn codoping and introduction of PbSe secondary phase contribute to remarkable enhancement of electrical conductivity and power factor. The peak power factor reaches to 5.43 mu W cm(-1) K-2 in Sn0.98Pb0.01Zn0.01Se. Phase-separation and nanostructuring strategies construct all-hierarchical architectures to scattering phonons. The lattice thermal conductivity is significantly reduced to 0.13 Wm(-1) K-1 through constructing all-hierarchical architectures and dual-atom point-defect scattering. A record high thermoelectric performance ZT = 2.2 was achieved in polycrystalline SnSe through enhancing electrical transport properties while keeping ultralow thermal conductivity. This work offers new strategies to realize high value of ZT in polycrystalline SnSe.