High Water Uptake from Air by Thiazole-Based Covalent Organic Frameworks and Their Scalable Synthesis

Sorption-based water harvesting from air offers an attractive solution to address global water stress on our planet. It requires sorbents with rapid low relative humidity (RH) uptake, long-term cycling, and scalable manufacturing. Here, we report a family of customizable thiazole-based β-ketoenamine covalent organic frameworks (COFs) where COF-1206 emerged as a leading candidate for water harvesting. This COF is readily scalable and can be cycled over 120 times without loss of capacity, exhibiting fast adsorption kinetics (less than 30 min to equilibrium), and delivering high atmospheric water harvesting (AWH) working capacity (0.47 g g-1 at RH = 40% and 298 K). COF-1206 is unique in combining high water uptake capacity, scalability, and long-term stability, enabling efficient AWH.