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This content will become publicly available on June 2, 2026

Title: Enhancing Water Harvesting Efficiency in a Phosphonate Metal–Organic Framework through Controlled Defect Generation
Global access to drinking water shrinks yearly, yet the atmosphere—our largest sustainable water source—remains largely untapped. Metal–organic frameworks (MOFs), a tunable class of crystalline porous materials, are promising candidates for atmospheric water harvesting. The channel-pore MOF STA-16(Co) stands out due to its robust phosphonate-based structure, which provides high stability and excellent water uptake. However, STA-16(Co) suffers from slow water uptake kinetics. To address this limitation, we introduced defects into STA-16(Co) by selectively removing linkers through treatment with nitrilotriacetic acid, significantly improving water diffusion kinetics. The defective MOFs demonstrate markedly faster water saturation rates—delivering ~50% more water in a 40-minute cycle—while maintaining the same uptake capacity and isothermal behavior as pristine STA-16(Co). Solid-state nuclear magnetic resonance analysis confirms that localized defects enhance efficiency without altering the overall pore geometry. This study presents a straightforward and generalizable strategy to optimize water sorption in channel-based MOFs.  more » « less
Award ID(s):
2119433
PAR ID:
10648728
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Materials Letters
Volume:
7
Issue:
6
ISSN:
2639-4979
Page Range / eLocation ID:
2255 to 2261
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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