Microfluidic Spinning Boosting Thermoelectric Performance of PEDOT:PSS Nonwoven Fabrics

Abstract Organic thermoelectric generators hold great promise for powering wearable microelectronics, yet their performance is fundamentally constrained by the trade-off between electrical conductivity ( σ ) and the Seebeck coefficient ( S ). Herein, we develop a microfluidic spinning platform to fabricate PEDOT:PSS-based nonwoven fabrics with precisely engineered micro-/nanoscale physical and electronic structures, substantially enhancing thermoelectric performance. The intense shear field and in situ coagulation within microfluidic microchannels, synergized with H 2 SO 4 treatment, promotes axial orientation and coil-to-linear conformational transition of PEDOT chains, achieving multiscale structural ordering for highly efficient charge transport in the resulting fibers. A subsequent controlled NaOH‑mediated dedoping process finely tunes the Fermi level and modulates energy‑dependent scattering, yielding a final σ of 2038 S cm −1 and an S of 29.7 μV K −1 . Such integrated modulation enables effective optimization of the classic σ - S trade-off, ultimately yielding a power factor of 179.8 μW m −1 K −2 . Furthermore, by integrating the fabric with an electrospun PVDF-HFP radiative-cooling layer, we demonstrate a radiation-modulated fabric device capable of maintaining an in-plane temperature gradient (Δ T ≈ 20 K) under natural sunlight and efficiently harvesting ambient solar-thermal energy. This study provides a versatile route for the fabrication of all-organic, flexible fabrics with high-performance thermoelectric functionality for wearable energy applications.