Shear‐Intensified Hybridization of Conjugated Polymer Fibers for Organic Electrochemical Transistors

High‐performance and mechanically robust conjugated polymer fibers are of great essence for advancing the capabilities of organic electrochemical transistors (OECTs)‐based wearable devices. Here, a novel shear‐intensified hybridization (SIH) via additive engineering strategy to significantly enhance poly(benzimidazobenzophenanthroline) (BBL) fibers is introduced. This approach leverages fluid shear during wet spinning with the precisely engineered incorporation of graphene oxide nanosheets, which are subsequently thermally reduced to functionalized graphene (FG). The resulting synergistic effects, driven by the SIH mechanism, lead to exceptional molecular orientation, enhanced π–π stacking, and strengthened interfacial interactions within the BBL/FG hybrid system. Optimized BBL/FG fibers exhibit a tensile strength of 208 MPa, showing excellent practical application potential. OECTs fabricated from the hybrid fibers demonstrate a 54% increase in normalized transconductance and a 45% enhancement in carrier mobility over pristine BBL fiber devices. Furthermore, an all‐fiber complementary inverter, built on these OECTs, achieves a high gain of 86 V/V for fiber electronics and successfully amplifies weak physiological signals. This work elucidates the SIH mechanism enabled by additive engineering and establishes a robust platform for high‐performance all‐fiber semiconducting circuits.