Interface-Induced In Situ Growth of Dense MOF Membrane for Solar-Assisted Freshwater Collection

Moisture collection using physisorbents emerges as a promising approach to alleviate water shortage in arid regions, yet its effectiveness hinges critically on the water-collecting capability and regeneration efficiency of the adsorbents. Here we introduce a metal-organic framework (MOF) derived membrane tailored for solar-driven freshwater production, achieved by employing an interface-induced in situ growth strategy. Based on a stable Al-MOF, HIAM-330, which exhibits high water adsorption capacity (405.91 mg g^-1 at 30% RH), we demonstrate the fabrication of a low macroscale defect-density membrane via in situ growth on hydrophilic-photothermal substrate directed by the synergistic effect of electrostatic attraction and hydrophilic interactions. The resulting membrane boasts a high MOF loading and showcases rapid solar-assisted regeneration, achieving a moisture conversion of 87.47% under practical low-humidity environment. Our strategy of constructing low macroscale defect-density MOF-derived membranes offers new insights into optimizing the moisture harvesting efficiency.