Liu Shuo, Li Airan, Hao Xiaowen, Chen Mengzhao, Huang Yi, Yu Yinde, Wang Chin-Wei, Ren Qingyong, Zhu Tiejun, Fu Chenguang
State Key Laboratory of Silicon and Advanced Semiconductor Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, China.
Spallation Neutron Source Science Center, Dongguan, China.
Sci Technol Adv Mater. 2025 May 28;26(1):2512702. doi: 10.1080/14686996.2025.2512702. eCollection 2025.
YbMnSb, a topological semimetal with an exotic band structure, has recently been found to exhibit potential thermoelectric transport properties in its single-crystalline formality. The fabrication of polycrystals, which have the advantages of easy synthesis and doping tunability, will advance the transport studies of YbMnSb but face challenges. Here, we found that the polycrystalline YbMnSb, synthesized using the conventional melting method, unexpectedly exhibits obvious impurities due to the competing phase YbMnSb. To avoid the high-temperature synthesis, high-quality polycrystalline bulk YbMnSb, as well as three other MnSb ( = Sr, Ba, Eu), were successfully prepared by mechanical alloying followed by spark plasma sintering. Based on the high-quality polycrystalline samples, it was discovered that YbMnSb reacts with oxygen during heating in the presence of small amounts of oxygen, resulting in MnSb, YbO, and Sb. A similar oxidation phenomenon also occurs for the other MnSb. This work provides a feasible method for synthesizing high-quality MnSb polycrystals, which should also be suitable for the other isostructural topological semimetals, paving the way for future studies of their transport properties.
YbMnSb是一种具有奇异能带结构的拓扑半金属，最近发现其单晶形式具有潜在的热电输运特性。多晶体具有易于合成和掺杂可调性的优点，其制备将推动YbMnSb的输运研究，但面临挑战。在此，我们发现采用传统熔炼法合成的多晶YbMnSb由于竞争相YbMnSb而意外地呈现出明显的杂质。为避免高温合成，通过机械合金化随后进行放电等离子烧结，成功制备了高质量的多晶块状YbMnSb以及其他三种MnSb（=Sr、Ba、Eu）。基于高质量的多晶样品，发现YbMnSb在少量氧气存在下加热时会与氧气反应，生成MnSb、YbO和Sb。其他MnSb也会出现类似的氧化现象。这项工作为合成高质量的MnSb多晶体提供了一种可行的方法，该方法也应适用于其他同构拓扑半金属，为其未来的输运性质研究铺平了道路。
