The development of high-performance, low-power active components directly integrated onto fibrous substrates is essential for the realization of next-generation wearable e-textiles. Here, we demonstrate high-performance monofilament fiber-based field-effect transistors (FETs) utilizing high-purity semiconducting single-walled carbon nanotubes (s-SWNTs) and solid-state electrolyte gate dielectrics. To overcome the challenges of patterning on curvilinear fiber surfaces, we developed a fine-thread shadow mask technique, enabling the precise definition of micro-scale channel gaps without complex photolithography. The s-SWNTs, isolated via a selective conjugated polymer wrapping method, exhibited robust ambipolar transport and high purity, as confirmed by UV-Vis-NIR and Raman spectroscopy. By integrating a EMIMBF4/PVDF-HFP solid-state electrolyte, the monofilament fiber-based FETs achieved ultra-low voltage operation (1.05 µF cm⁻²). The resulting fiber transistors exhibited a high hole mobility of 14.7 cm² V⁻¹ s⁻¹ and a transconductance (gm/W) of 0.3 S m⁻¹. This synergistic approach combining textile-compatible fabrication and high-mobility nanomaterials provides a scalable pathway for energy-efficient, in-cloth signal processing and logic circuitry.
Khim et al. (Wed,) studied this question.