Tailor-made hygroscopic photothermal organogels for moisture management and evaporative cooling through a 1D-to-3D design†

Abstract

Sorption-based moisture management and evaporative cooling are emerging technologies with significant potential for energy-efficient personal thermal management (PTM). However, developing customized hygroscopic composites that combine effective humidity control, heat dissipation, and wearer comfort remains a key challenge. This work introduces multidimensional organogels (1D to 3D) that synergize hygroscopic, photothermal, mechanical and processing properties for user-defined PTM applications. Selected polycations, polyanions, zwitterionic polymers and glycerol are properly cross-linked within 1D fibers through continuous wet-spinning, preventing the need for hygroscopic salts and moisture-induced structural degradation. 2D blended fabrics integrate the hygroscopicity and flexibility of organogel-based fibers with the strength and wear resistance of synthetic fibers, enabling two passive heating methods to enhance solar-powered water release. Optimized fabrics demonstrate reliable and reversible moisture sorption/desorption, enduring up to six cycles per day under outdoor conditions. The efficient evaporative cooling and heat stress dissipation make them ideal for PTM textiles and clothing. Furthermore, 3D printed hierarchical matrices expand the organogels' potential to PTM insoles. With exceptional moisture control, scalability and processing ease, these organogels rank among the best-performing and highly customizable hygroscopic materials. This work represents one of the few hygroscopic photothermal organogels offering self-contained and application-specific functions through 1D to 3D designs.