Polycrystalline SnSe with a thermoelectric figure of merit greater than the single crystal.
Polycrystalline SnSe with a thermoelectric figure of merit greater than the single crystal.
复制标题
热电优值大于单晶的多晶SnSe。
DOI：
10.1038/s41563-021-01064-6
复制
发表时间：
2021-10
期刊：
影响因子：
41.2
通讯作者：
Chung I
中科院分区：
文献类型：
--
作者：
Zhou C;Lee YK;Yu Y;Byun S;Luo ZZ;Lee H;Ge B;Lee YL;Chen X;Lee JY;Cojocaru-Mirédin O;Chang H;Im J;Cho SP;Wuttig M;Dravid VP;Kanatzidis MG;Chung I
热电材料从废热中产生电能，转换效率由无量纲品质因数ZT决定。单晶硒化锡(SnSe)在913 K时表现出约2.2-2.6的高ZT，但同一化合物的更实用和可展开的多晶版本的整体ZT要差得多，从而阻碍了成本效益高的无铅热电材料的前景。多晶块体性能差的原因是SnSe粉末表面覆盖着微量的锡氧化物，它增加了热导率，降低了电导率，从而降低了ZT。在这里，我们报道了经过试剂提纯和去除锡氧化物的空穴掺杂SnSe多晶样品，在783K时的ZT约为3.1，其晶格热导率在783 K时约为0.07 W m-1 K-1，低于单晶。在多晶样品中获得超高热电性能的途径是从SnSe颗粒表面适当地去除有害的导热氧化物。这些结果可能开启由这种高性能材料制造高性能实用热电材料的时代。SnSe具有非常高的热电优值ZT，但多晶样品具有比单晶更高的晶格热导率。在这里，通过控制锡试剂纯度和去除SnOx杂质，可以获得较低的导热系数，使ZT在783K. 时达到3.1.
Thermoelectric materials generate electric energy from waste heat, with conversion efficiency governed by the dimensionless figure of merit, ZT. Single-crystal tin selenide (SnSe) was discovered to exhibit a high ZT of roughly 2.2–2.6 at 913 K, but more practical and deployable polycrystal versions of the same compound suffer from much poorer overall ZT, thereby thwarting prospects for cost-effective lead-free thermoelectrics. The poor polycrystal bulk performance is attributed to traces of tin oxides covering the surface of SnSe powders, which increases thermal conductivity, reduces electrical conductivity and thereby reduces ZT. Here, we report that hole-doped SnSe polycrystalline samples with reagents carefully purified and tin oxides removed exhibit an ZT of roughly 3.1 at 783 K. Its lattice thermal conductivity is ultralow at roughly 0.07 W m–1 K–1 at 783 K, lower than the single crystals. The path to ultrahigh thermoelectric performance in polycrystalline samples is the proper removal of the deleterious thermally conductive oxides from the surface of SnSe grains. These results could open an era of high-performance practical thermoelectrics from this high-performance material. SnSe has a very high thermoelectric figure of merit ZT, but uncommonly polycrystalline samples have higher lattice thermal conductivity than single crystals. Here, by controlling Sn reagent purity and removing SnOx impurities, a lower thermal conductivity is achieved, enabling ZT of 3.1 at 783 K.
登录
查看更多内容
影响因子：
64.8
作者：
Biswas, Kanishka;He, Jiaqing;Kanatzidis, Mercouri G.
通讯作者：
Kanatzidis, Mercouri G.
影响因子：
64.8
作者：
Hinterleitner, B.;Knapp, I.;Bauer, E.
通讯作者：
Bauer, E.
影响因子：
15
作者：
Lee, Yong Kyu;Ahn, Kyunghan;Chung, In
通讯作者：
Chung, In
影响因子：
3.5
作者：
Rudtsch, S
通讯作者：
Rudtsch, S
通过引入 Sn 空位在多晶 SnSe 中实现高热电品质因数
影响因子：
15
作者：
Wei, Wei;Chang, Cheng;Tang, Guodong
通讯作者：
Tang, Guodong