The organic thermoelectric fibers with p- and n-type power factors of 378 ± 56 and 289 ± 98 μW m−1 K−2, respectively, were prepared via simple wet-spinning and post-treatment methods.

Free-standing single-walled carbon nanotube (SWCNT)/cellulose acetate composite films were fabricated by a simple bar-coating method. As a paste solvent, acetone, a low-boiling-point solvent, was used. By simple brushing of a polyethylenimine/ethanol solution, ntype thermoelectric composite films could be obtained. The optimal p-type and n-type power factors of the free-standing thermoelectric films were 1.41 ± 0.22 and 0.516 ± 0.172 μW cm −1 K −2 , respectively, at room temperature. We also fabricated the organic thermoelectric generator from the free-standing composite films and confirmed their electrical power generation capability. By applying the temperature difference of 10 K, the output power of 2.28 μW was obtained.

Freestanding single-walled carbon nanotube (SWCNT) buckypapers with thicknesses of ∼30 μm are fabricated using a simple bar-coating process. The Seebeck coefficient and electrical conductivity of the SWCNT buckypapers are affected by the composition of the dispersion solvent mixture. The maximum p-type power factor of a SWCNT buckypaper is 411 ± 13 μW m–1 K–2. The inverse relationship between the Seebeck coefficient and electrical conductivity of the SWCNT buckypapers may be explained by the number density of junctions between the SWCNT bundles. Using the SWCNT buckypapers, which can be cut, folded, and pasted, a foldable thermoelectric generator is fabricated. The thermoelectric generator folded to an area of 2.25 cm2 exhibits a maximum power of 10.3 μW at a vertical temperature difference of 30 K.