Zhu Yongbin, Han Zhijia, Han Bing, Jiang Feng, Wu Xinzhi, Han Cheng-Gong, Deng Yonghong, Liu Weishu
School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
ACS Appl Mater Interfaces. 2021 Dec 1;13(47):56164-56170. doi: 10.1021/acsami.1c16299. Epub 2021 Nov 16.
Nano approaches are practical strategies to boost the thermoelectric figure of merit due to the strong phonon scattering from the grain boundaries and nanoinclusions. Here, we have reported a strong phonon scattering at the heterogeneous interfaces of MgSn/MgSb high-content nanocomposites (HCnCs). As a result, a significantly reduced lattice thermal conductivity of 1.09 W m K was observed in the equimolar MgSn/MgSb HCnC, 80% lower than pure MgSn and 25% lower than pure MgSb. As a result, a high ∼ 1.13 at 773 K was achieved in the MgSn/MgSb HCnC. Furthermore, various defects, including solid solutions, nanoinclusions, and misfit dislocations, were observed in both the MgSb phase and the MgSn phase through the microstructure characterization.
由于晶界和纳米夹杂物产生的强声子散射，纳米方法是提高热电优值的实用策略。在此，我们报道了MgSn/MgSb高含量纳米复合材料（HCnCs）的异质界面处存在强声子散射。结果，在等摩尔MgSn/MgSb HCnC中观察到晶格热导率显著降低至1.09 W m⁻¹ K，比纯MgSn低80%，比纯MgSb低25%。因此，MgSn/MgSb HCnC在773 K时实现了高达约1.13的热电优值。此外，通过微观结构表征在MgSb相和MgSn相中均观察到了各种缺陷，包括固溶体、纳米夹杂物和失配位错。
