Microfluidic Spinning Boosting Thermoelectric Performance of PEDOT:PSS Nonwoven Fabrics

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 H₂SO₄ 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 (ΔT ≈ 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.