Thermoelectric fibers from well-dispersed carbon nanotube/poly(vinyliedene fluoride) pastes for fiber-based thermoelectric generators†
High-performance thermoelectric composite fibers were prepared via simple wet-spinning of single-walled carbon nanotube (SWCNT)/poly(vinylidene fluoride) (PVDF) pastes using a common solvent/coagulation system. By improving the content and dispersion state of SWCNTs in the composite fibers, the thermoelectric performance could be effectively enhanced. With n-type doping of SWCNTs using polyethylenimine, high-performance n-type SWCNT/PVDF composite fibers could be prepared. The power factors of the p- and n-type SWCNT/PVDF composite fibers with the SWCNT content of 50 wt% were 378 ± 56 and 289 ± 98 μW m−1 K−2, respectively. The electric power generation capability of an organic thermoelectric generator with the p- and n-type composite fibers was confirmed.