Li Juan, Liu Kejia, Ma Xiaojing, Yang Zhongran, Yi Liqun, Mao Jun, Zhang Qian
School of Materials Science and Engineering and Institute of Materials Genome & Big Data, Harbin Institute of Technology, Shenzhen 518055, China.
State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, China.
Inorg Chem. 2024 Oct 28;63(43):20126-20132. doi: 10.1021/acs.inorgchem.4c00522. Epub 2024 Apr 30.
A P-type MgSb-based Zintl phase compound has been considered a promising candidate for thermoelectric applications. Alloying, which introduces a high concentration of point defects, is particularly effective in scattering phonons and reducing lattice thermal conductivity. Herein, alloying in p-type MgNaSb via the introduction of elements like Yb, Eu, Ca, and Ba was realized, and the room-temperature lattice thermal conductivity has been effectively reduced to ∼1.1 W m K. To further intensify the phonon scattering, two groups of elements (Eu and Cd, and Yb and Cd) were chosen for heavy alloying at the Mg site, and the lattice thermal conductivity of MgEuCdNaSb was further reduced to ∼0.45 W m K. Eventually, a peak as high as ∼1.0 was achieved at 773 K, and the compound outperforms the previously reported p-type MgSb compounds.
一种基于P型MgSb的津特耳相化合物被认为是热电应用的一个有前途的候选材料。引入高浓度点缺陷的合金化在散射声子和降低晶格热导率方面特别有效。在此，通过引入Yb、Eu, Ca和Ba等元素实现了p型MgNaSb中的合金化，室温晶格热导率已有效降低至1.1 W m⁻¹ K⁻¹。为了进一步增强声子散射，选择了两组元素（Eu和Cd，以及Yb和Cd）在Mg位点进行重合金化，MgEuCdNaSb的晶格热导率进一步降低至0.45 W m⁻¹ K⁻¹。最终，在773 K时实现了高达~1.0的峰值，该化合物的性能优于先前报道的p型MgSb化合物。
