单晶和多晶SnSe热电性能对比

硒化锡材料因为其优良的ZT性能，有巨大的热发电应用潜力。此文我们详细地对比了单晶和多晶硒化锡在热力学和电性能输运方面的差异。其中，单晶样品是通过布里奇曼法合成的，多晶样品是通过熔融、粉碎和SPS烧结合成的。热电性能的测量则是通过四探针法和激光闪射法完成的。我们发现单晶样品的功率因子是多晶的2倍，而热导率也是多晶样品的3倍左右，这就直接导致了单晶和多晶的最高ZT值差异不大。单晶硒化锡在823 K处取得最高ZT 为0.65，而多晶则是在923K 取得最高ZT为0.5. 这些发现可以为系统地探索硒化锡材料的热电应用提供坚实的基础。

Title: Thermoelectric Properties Difference between Single Crystal and Polycrystalline SnSeHong-Xing Mi, Huan-Yong Li, Cun-Yun Qiao, Ting Zhang, Li Han and Ju Xu*

SnSe is a robust candidate for thermoelectric applications due to its excellent ZT performance. We compare single crystal and polycrystalline SnSe in thermal and electrical properties. The single crystal is synthesized with Bridgeman method, while the polycrystalline is synthesized with melting and SPS. The thermoelectric properties of both materials are measured with four-probe method and laser flash method. The results show power factor of single crystal is twice higher than that of polycrystalline, and thermal conductivity of single crystal are also thrice higher at all temperature range, leading to comparable highest ZT of those two materials. The highest ZT single crystal is 0.65 at 823 K, and 0.5 at 923 K for polycrystalline. These findings yield a foundation for the systematic exploration of SnSe thermoelectric application.