Direct Wet-Spun Single-Walled Carbon Nanotubes-Based p-n Segmented Filaments toward Wearable Thermoelectric Textiles.

Three-dimensional thermoelectric (TE) textiles (TETs) fabricated with TE filaments (TEFs) possess merits over other types such as thickness-direction thermal energy harvesting and excellent conformability with dynamic body curves, revealing the prospect of generating electricity for on-body application. Nonetheless, there is still a lack of a costless but scalable method to automatically and seamlessly produce in-series interconnected p-n segmented TEFs with high TE properties via conventional fiber spinning processes. Here, we developed an alternate wet-spinning strategy to continuously manufacture single-walled carbon nanotube-based p-n segmented TEFs at large scale. The TEF with high electrical conductivity (400-800 S cm -1 ) displays a low contact resistivity of 189.8 μΩ cm 2 between the segments and interelectrode, showing 2 orders of magnitude smaller than that reported in the literature. More importantly, the power factors of p -type and n -type segments are 26.25 and 17.14 μW m -1 K -2 , respectively, which are 3 and 4 orders of magnitude higher than those of advanced studies. We finally embroidered it into spacer fabric to fabricate a wearable TET, demonstrating an output power density of 501 nW m -2 at Δ T = 27.7 K. The methodology can inspire the development of fiber-based electronics such as wearable TEs and diodes and so forth.