Single‐Crystal SnSe Thermoelectric Fibers via Laser‐Induced Directional Crystallization: From 1D Fibers to Multidimensional Fabrics

• Published in: Advanced materials (Weinheim) Vol. 32; no. 36; pp. e2002702 - n/a
• Main Authors: Zhang, Jing, Zhang, Ting, Zhang, Hang, Wang, Zhixun, Li, Chen, Wang, Zhe, Li, Kaiwei, Huang, Xingming, Chen, Ming, Chen, Zhe, Tian, Zhiting, Chen, Haisheng, Zhao, Li‐Dong, Wei, Lei
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.09.2020
• Subjects: Carbon dioxide; Carbon dioxide lasers; Crystal structure; Crystallization; Fabrics; Fibers; flexible fibers; high thermoelectric properties; laser recrystallization; Materials science; single‐crystal SnSe; Substrates; Thermoelectric materials; Tin selenide; wearable fabrics; Wearable technology
• DOI: 10.1002/adma.202002702
• ISSN: 0935-9648; 1521-4095

Single‐crystal tin selenide (SnSe), a record holder of high‐performance thermoelectric materials, enables high‐efficient interconversion between heat and electricity for power generation or refrigeration. However, the rigid bulky SnSe cannot satisfy the applications for flexible and wearable devices. Here, a method is demonstrated to achieve ultralong single‐crystal SnSe wire with rock‐salt structure and high thermoelectric performance with diameters from micro‐ to nanoscale. This method starts from thermally drawing SnSe into a flexible fiber‐like substrate, which is polycrystalline, highly flexible, ultralong, and mechanically stable. Then a CO2 laser is employed to recrystallize the SnSe core to single‐crystal over the entire fiber. Both theoretical and experimental studies demonstrate that the single‐crystal rock‐salt SnSe fibers possess high thermoelectric properties, significantly enhancing the ZT value to 2 at 862 K. This simple and low‐cost approach offers a promising path to engage the fiber‐shaped single‐crystal materials in applications from 1D fiber devices to multidimensional wearable fabrics. Single‐crystal SnSe fibers are achieved using thermal drawing and laser‐induced recrystallization. The resulting single‐crystal rock‐salt SnSe fibers possess high thermoelectric properties, enhancing the ZT value close to 2 at 860 K, while being highly flexible, ultralong, and mechanically stable. This simple and low‐cost approach engages the fiber‐shaped high‐performance single‐crystal materials in applications from 1D fiber devices to multidimensional wearable fabrics.