Jin Qun, Jiang Song, Zhao Yang, Wang Dong, Qiu Jianhang, Tang Dai-Ming, Tan Jun, Sun Dong-Ming, Hou Peng-Xiang, Chen Xing-Qiu, Tai Kaiping, Gao Ning, Liu Chang, Cheng Hui-Ming, Jiang Xin
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China.
University of Chinese Academy of Sciences, Shenyang, China.
Nat Mater. 2019 Jan;18(1):62-68. doi: 10.1038/s41563-018-0217-z. Epub 2018 Nov 19.
Inorganic chalcogenides are traditional high-performance thermoelectric materials. However, they suffer from intrinsic brittleness and it is very difficult to obtain materials with both high thermoelectric ability and good flexibility. Here, we report a flexible thermoelectric material comprising highly ordered BiTe nanocrystals anchored on a single-walled carbon nanotube (SWCNT) network, where a crystallographic relationship exists between the BiTe <[Formula: see text]> orientation and SWCNT bundle axis. This material has a power factor of ~1,600 μW m K at room temperature, decreasing to 1,100 μW m K at 473 K. With a low in-plane lattice thermal conductivity of 0.26 ± 0.03 W m K, a maximum thermoelectric figure of merit (ZT) of 0.89 at room temperature is achieved, originating from a strong phonon scattering effect. The origin of the excellent flexibility and thermoelectric performance of the BiTe-SWCNT material is attributed, by experimental and computational evidence, to its crystal orientation, interface and nanopore structure. Our results provide insight into the design and fabrication of high-performance flexible thermoelectric materials.
无机硫族化物是传统的高性能热电材料。然而，它们具有固有的脆性，很难获得兼具高热电性能和良好柔韧性的材料。在此，我们报道了一种柔性热电材料，它由锚定在单壁碳纳米管（SWCNT）网络上的高度有序的BiTe纳米晶体组成，其中BiTe <[公式：见原文]> 取向与SWCNT束轴之间存在晶体学关系。这种材料在室温下的功率因子约为1600 μW m K，在473 K时降至1100 μW m K。其面内晶格热导率低至0.26±0.03 W m K，室温下实现了0.89的最大热电优值（ZT），这源于强烈的声子散射效应。通过实验和计算证据表明，BiTe-SWCNT材料优异的柔韧性和热电性能源于其晶体取向、界面和纳米孔结构。我们的结果为高性能柔性热电材料的设计和制造提供了见解。
