(220f) Macroscopic Weavable Fibers of Carbon Nanotubes with Giant Thermoelectric Power Factor

Thermoelectric materials convert heat into electricity and vice versa, offering great potential for waste heat recovery and solid-state cooling. Carbon nanotubes (CNTs) are promising candidates because of their one-dimensionality along with their unique advantages such as flexibility and light weight. However, preserving the large power factor of individual carbon nanotubes in macroscopic assemblies has been challenging. Here, we studied the thermoelectric properties of aligned CNT fibers with an ultrahigh electrical conductivity (>10⁶ Sm^-1) [1] and observed a giant thermoelectric power factor of 14±5 mWm^-1K^-2 [2]. The observed giant power factor originates from the ultrahigh electrical conductivity achieved through excellent sample morphology, combined with an enhanced Seebeck coefficient through Fermi energy tuning. The unique properties of CNT fibers, weavability, and scalability, combined with the excellent power factor, allowed us to fabricate a textile thermoelectric generator with enough output power to drive a light-emitting diode. Our findings open a route to provide renewable energy production by powerful and weavable thermoelectric generators.

References
[1] L. W. Taylor et al., Carbon, 171, 689 (2021)
[2] N. Komatsu et al., Nat. Commun., 12, 4931 (2021)