In this work, we report the synthesis of two novel isoreticular furan-based metal–organic frameworks (MOFs), namely MOF-LA2-1(furan) and MOF-LA2-2(furan). These MOFs are promising atmospheric water harvesters due to their high working water capacities and excellent durability. Specifically, MOF-LA2-1(furan) and MOF-LA2-2(furan) demonstrated working capacities of 0.41 g_water/g_MOF and 0.48 g_water/g_MOF under isobaric conditions of 1.70 kPa, respectively. They also exhibited no loss in water uptake even after undergoing 165 water adsorption-desorption cycles. The robustness of such MOFs against hydrolysis was more thoroughly investigated using ab initio periodic density functional theory (DFT) computations to dissect the effects of different secondary-building units (SBUs) and 'long arm' extension strategies on water stability. Additionally, MOF-LA2-2(furan) is notable as the first aluminum MOF to employ a double 'long arm' extension strategy, confirmed through single-crystal X-ray diffraction (SCXRD). This study not only highlights the synthesis of two new water-harvesting MOFs with high water absorption capacities but also gives insights into how future MOFs can be designed to improve their long-term durability against hydrolysis.

Chemical structures of H<sub>2</sub>FVDC and H<sub>2</sub>FDP linkers and the coordinative environment of the <i>cis </i>corner-shared SBU (a), forming the MOF-LA2-1(furan) (left) and MOF-LA2-2(furan) (right) frameworks. (b) show linker conformations, while <i>z</i>-axis views (c) highlight their cuboid 1D channels, formed by four <i>cis </i>corner-shared SBUs. Aluminum coordination is depicted with polyhedral symbols. Color code: Al in blue; C in gray; O in red; hydrogen omitted for clarity.

Chemical structures of H₂FVDC and H₂FDP linkers and the coordinative environment of the cis corner-shared SBU (a), forming the MOF-LA2-1(furan) (left) and MOF-LA2-2(furan) (right) frameworks. (b) show linker conformations, while z-axis views (c) highlight their cuboid 1D channels, formed by four cis corner-shared SBUs. Aluminum coordination is depicted with polyhedral symbols. Color code: Al in blue; C in gray; O in red; hydrogen omitted for clarity.

Ali Alawadhi

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