Abstract
Conventional thermal regeneration of solid desiccants is often hindered by high energy consumption. To address this challenge, we propose a novel scheme that eliminates the need for preheating the return air to regenerate the desiccant. Instead, moisture removal is achieved directly via electrothermal heating. To realize this, we employed a composite film strategy based on PEDOT:PSS and PVA, leveraging PEDOT:PSS's dual hydrophilic and conductive properties while using PVA to improve mechanical robustness. EG is commonly used as a dopant and is considered to promote a conformational change of PEDOT chains from coiled to expanded structures. This transition may contribute to a more continuous conductive network and enhance π-π stacking and charge transport. Multiscale characterization and device-relevant testing were conducted to link the morphology and surface composition to mechanical durability, electrothermal stability, and moisture-sorption behavior. The composites demonstrated significant mechanical stability under cyclic tensile loading. Incorporating PVA markedly improved the mechanical robustness of the otherwise brittle PEDOT:PSS, increasing the elongation at the break to 630%. Moreover, the film maintained structural integrity during 100 loading-unloading tensile cycles to 20% strain under 25 °C and 80% RH. Electrothermal durability tests showed no significant electrical degradation during 12 h of continuous powering, indicating prolonged electrical stability. Water-vapor sorption measurements indicated that introducing PVA reduced the saturated uptake to 82% of the pristine film; nevertheless, the selected formulation (PP6) still exhibited a high absorption capacity of 1132.80 cm(3) (STP) g(-1) at P/P(0) = 0.94, demonstrating strong moisture uptake in the high-humidity regime. Based on comprehensive performance evaluation, PP6 was used to produce the dehumidification element. The element displayed reversible absorption-desorption during electrothermal regeneration in cycling tests powered by approximately 10 W, confirming the composite's viability via an electro-driven pathway. Overall, this study demonstrates a self-standing PEDOT:PSS-based polymer desiccant that simultaneously achieves humid-state mechanical durability and long-term electrothermal stability, enabling stable low-power regeneration cycling without thermally preheating high-flow-rate return air.