Ultrahigh thermoelectric properties of p ‐type Bi x Sb 2− x Te 3 thin films with exceptional flexibility for wearable energy harvesting

• Published in: Carbon energy 2024-08, Vol.6 (8)
• Main Authors: Zheng, Zhuang‐Hao, Zhong, Yi‐Ming, Li, Yi‐Liu, Nisar, Mohammad, Mansoor, Adil, Li, Fu, Chen, Shuo, Liang, Guang‐Xing, Fan, Ping, Xu, Dongyan, Wei, Meng, Chen, Yue‐Xing
• Format: Article
• Language: English
• ISSN: 2637-9368; 2637-9368
• DOI: 10.1002/cey2.541

Use of a flexible thermoelectric source is a feasible approach to realizing self‐powered wearable electronics and the Internet of Things. Inorganic thin films are promising candidates for fabricating flexible power supply, but obtaining high‐thermoelectric‐performance thin films remains a big challenge. In the present work, a p ‐type Bi x Sb 2− x Te 3 thin film is designed with a high figure of merit of 1.11 at 393 K and exceptional flexibility (less than 5% increase in resistance after 1000 cycles of bending at a radius of ∼5 mm). The favorable comprehensive performance of the Bi x Sb 2− x Te 3 flexible thin film is due to its excellent crystallinity, optimized carrier concentration, and low elastic modulus, which have been verified by experiments and theoretical calculations. Further, a flexible device is fabricated using the prepared p ‐type Bi x Sb 2− x Te 3 and n ‐type Ag 2 Se thin films. Consequently, an outstanding power density of ∼1028 μW cm −2 is achieved at a temperature difference of 25 K. This work extends a novel concept to the fabrication of high‐performance flexible thin films and devices for wearable energy harvesting.