  Conjugated polymer fibers can be used to manufacture various soft fibrous
optoelectronic devices, significantly advancing wearable devices and smart
textiles. Recently, conjugated polymer-based fibrous electronic devices have
been widely used in energy conversion, electrochemical sensing, and
human-machine interaction. However, the insufficient mechanical properties of
conjugated polymer fibers, the difficulty in solution processing semiconductors
with rigid main chains, and the challenges in large-scale continuous production
have limited their further development in the wearable field. We regulated the
pi - pi stacking interactions in conjugated polymer molecules below their
critical liquid crystal concentration by applying fluid shear stress. We
implemented secondary orientation, leading to the continuous fabrication of
anisotropic semiconductor fibers. This strategy enables conjugated polymers
with rigid backbones to synergistically enhance the mechanical and
semiconductor properties of fibers through liquid crystal spinning.
Furthermore, conjugated polymer fibers, exhibiting excellent electrochemical
performance and high mechanical strength (600 MPa) that essentially meet the
requirements for industrialized preparation, maintain stability under extreme
temperatures, radiation, and chemical reagents. Lastly, we have demonstrated
logic circuits using semiconductor fiber organic electrochemical transistors,
showcasing its application potential in the field of wearable fabric-style
logic processing. These findings confirm the importance of the liquid
crystalline state and solution control in optimizing the performance of
conjugated polymer fibers, thus paving the way for developing a new generation
of soft fiber semiconductor devices.
