[8a-PB2-1~32] 12.3 Functional Materials and Novel Devices

[8a-PB2-18] Thermoelectric properties of n-type CNT/perovskite composite yarns in high-temperature environments

〇Yudai Iwata¹, Aghnia Heriyanto¹, Nguyen Anh¹, Ryota Fukuzawa¹, Hiroaki Benten¹, Masakazu Nakamura¹ (1.NAIST)

Keywords:

Carbon nanotube,Thermoelectric conversion,Perovskite

Lightweight and flexible carbon nanotube (CNT) spun yarns have attracted attention as promising materials for flexible thermoelectric devices; however, suppressing thermal conductivity is crucial for improving thermoelectric performance. To date, we have fabricated CNT/perovskite composite yarns by inserting two-dimensional hybrid perovskite nanocrystals between CNT bundles, successfully reducing thermal conductivity to approximately one-third of its original value. Furthermore, for practical application as thermoelectric materials, achieving n-type conduction in the composite yarns and ensuring stability in air and over a wide temperature range are critical challenges. In this study, aiming to fabricate n-type composite yarns that operate stably in air over a temperature range of 25–140°C, we applied a doping method using benzocrown-6-ether-stabilized K+ ions as the positive counter charge, as well as a doping method utilizing the amino groups of polyethyleneimine (PEI) as an electron donor and coating the CNT surface with the same polymer, and evaluated their thermoelectric properties and thermal stability.