Freestanding PANI/1T-MoS₂ composite films via facile drop-casting for high-performance flexible thermoelectrics

Aiming at wearable low-grade heat harvesting, we developed a facile drop‑casting strategy to fabricate freestanding polyaniline/1 T-phase molybdenum disulfide (PANI/1 T-MoS 2 ) composite thick films (~37 μm), using m -cresol as the processing solvent and camphorsulfonic acid (CSA) as the dopant. The composite films successfully decouple the conventional trade-off between electrical conductivity ( σ ) and Seebeck coefficient ( S ) through interfacial coupling and carrier regulation enabled by 1 T-MoS 2 . The optimized PANI‑MoS 2 ‑25 sample delivers a maximum power factor ( PF ) of 26.18 μW·m −1 ·K −2 at 378 K, representing an ~19‑fold enhancement over pristine PANI, together with a low thermal conductivity of 0.22 W·m −1 ·K −1 at 298 K, yielding a ZT ≈ 0.05. The film exhibits excellent mechanical reliability, retaining 94.1% of its initial σ and 96.3% of its initial S after 1000 bending cycles at a radius of 8 mm. A ten‑leg series‑connected flexible thermoelectric generator (F‑TEG) assembled from this film produces an open‑circuit voltage of 4.781 mV at Δ T  = 10 K (simulating body‑heat harvesting) and 20.716 mV at Δ T  = 43 K, with a maximum output power of 0.729 μW and a peak power density of 9.1 μW·cm −2 . This work provides a feasible material platform and processing route for developing wearable thermoelectric devices that combine high output performance, remarkable flexibility, and simple fabrication.