Shape-Deformable Thermoelectric Carbon Nanotube Doughs

Abstract

In this study, shape-deformable thermoelectric p- and n-type doughs are fabricated by blending single-walled carbon nanotubes with excess amounts of nonvolatile liquid surfactants for efficient energy harvesting from diverse heat sources. The shape-deformable thermoelectric doughs exhibit touch-healing properties and can be easily molded into arbitrary shapes by simple shaping methods, such as those commonly used for rubber play dough. We used cube-shaped thermoelectric doughs to fabricate a vertical thermoelectric generator. Considering the shape-deformable properties of the thermoelectric doughs, a contraction strain of ~2% in the through-plane direction of the thermoelectric generator can be applied for an effective application of ∆T. We show that the thermoelectric generator we built with eight p-n pairs exhibits a maximum output power of 2.2 μW at a vertical ∆T of 15 K. Our results demonstrate the energy harvesting capability of thermoelectric generators with shape-deformable p- and n-type doughs. Owing to the properties of this material, thermoelectric generators with various device geometries can be fabricated for energy harvesting from a diverse range of non-flat heat sources.