Different macroporous characteristic LiCl/CaCl2 binary salt double network hygroscopic aerogels for atmospheric water harvesting

s Sorption-based atmospheric water harvesting (SAWH) is an emerging strategy for decentralized freshwater acquisition. Developing advanced materials considering the synergistic effects of chemical composition and physical structure to improve water collection efficiency remains a current research hotspot and challenge. In this study, binary salt double network porous hygroscopic aerogels PAM/SA/FCNT/CaCl 2 /LiCl aerogel (PSFCL) and PAM/SA/FCNT/CaCl 2 /LiCl aerogel without swelling (N-PSFCL) with distinct macroporous scales were synthesized by controlling the swelling condition. The mechanical properties were significantly improved due to the formation of double networks by free radical polymerization and ionic cross-linking. PSFCL with larger pore size synergistically improved salt loading capacity (2.42 g·g −1 ) and water transport efficiency, achieving a water sorption capacity of 5.32 g·g −1 and a sorption rate of 1.89 g·g −1 ·h −1 at 90 % relative humidity, with a desorption rate of 1.01 g·g −1 ·h −1 at 1 kW·m −2 solar radiation intensity. This “trinity” design strategy of high water sorption capacity, rapid sorption-desorption kinetics, and superior mechanical properties provides a promising approach for future multifunctional atmospheric water harvesting gels.