Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004, People's Republic of China.
Nanotechnology. 2016 Oct 14;27(41):415704. doi: 10.1088/0957-4484/27/41/415704. Epub 2016 Sep 5.
Here, we present the successful fabrication of Te/TiS2 heterostructure nanocables with enhanced thermoelectric (TE) performance by a two-step route (a facile solvothermal approach for Te nanowires and then the Te nanowires are used as templates for the controllable growth of the Te/TiS2 nanocables), which is scalable for practical nanodevice applications. The heterostructure nanocables of different sizes can be prepared by varying the synthetic composition. Measurements of the Seebeck coefficient (S), electrical conductivity (σ), and thermal conductivity (κ) are carried out on the same nanowires over a temperature range of 2-350 K. The heterostructure nanocables show an ultrahigh power factor (S(2) σ) with a maximum value of 0.58 Wm(-1) K(-2), which comes from a high electrical conductivity and a strongly enhanced Seebeck coefficient. The figure of merit (ZT) can reach 1.91 at room temperature from a single nanocable with a diameter of 60 nm, which is thought to contribute to the formation of the hetero-phase core/shell structure. These results are expected to open up new application possibilities in nanoscale TE devices based on individual Te/TiS2 heterostructure nanocables.
在这里，我们通过两步法（一种简便的溶剂热法用于制备 Te 纳米线，然后将 Te 纳米线用作可控生长 Te/TiS2 纳米电缆的模板）成功制备了具有增强热电（TE）性能的 Te/TiS2 异质结构纳米电缆，这对于实际的纳米器件应用是可扩展的。通过改变合成成分，可以制备不同尺寸的异质结构纳米电缆。在 2-350 K 的温度范围内，对相同的纳米线上的塞贝克系数（S）、电导率（σ）和热导率（κ）进行了测量。异质结构纳米电缆表现出超高的功率因子（S(2) σ），最大值为 0.58 Wm(-1) K(-2)，这来自于高电导率和强烈增强的塞贝克系数。从直径为 60nm 的单个纳米电缆中，在室温下的品质因数（ZT）可达到 1.91，这被认为是形成异质相核/壳结构的原因。这些结果有望为基于单个 Te/TiS2 异质结构纳米电缆的纳米级 TE 器件开辟新的应用可能性。
