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Machines have continually developed with the needs of daily life and industrial applications. While the careful design of molecular‐scale devices often displays enhanced properties along with mechanical movements, controlling mechanics within solid‐state molecular structures remains a significant challenge. Here, we explore the distinct mechanical properties of zeolitic imidazolate frameworks (ZIFs)—frameworks that contain hidden mechanical components. Using a combination of experimental and theoretical approaches, we uncover the machine‐like capabilities of ZIFs, wherein connected composite building units operate similarly to a mechanical linkage system. Importantly, this research suggests that certain ZIF subunits act as core mechanical components, paving an innovative view for the future design of solid‐state molecular machines. [ABSTRACT FROM AUTHOR]

Porous materials have attracted considerable interest as water sorbents due to their potential in a broad range of water sorption‐related applications. Metal–organic frameworks (MOFs) are particularly notable for their high porosity and tunability. However, their limited hydrolytic stability often results in pore collapse, which significantly hinders their water sorption performance. To address this issue, an innovative design strategy based on reticular chemistry is essential to enhance structural stability and ensure efficient water sorption. Herein, a novel synthetic approach for constructing a merged‐net MOF structure using metallolinkers is introduced. Specifically, a porphyrin linker is employed to successfully synthesize a porphyrin‐based merged‐net MOF, UPF‐5. This MOF demonstrates significantly enhanced hydrolytic stability and improved water sorption performance while maintaining high pore volume. Additionally, the structure of UPF‐5 allows for the modification of accessible Zr6 nodes, enabling control over the pore environments and fine‐tuning the water sorption properties. This programmable synthetic strategy for porphyrin‐based merged‐net MOFs not only significantly enhances the structural stability for practical applications, including water sorption, but also advances reticular chemistry by discovering unprecedented topologies in MOF chemistry. [ABSTRACT FROM AUTHOR]

Paper crafts, such as origami and kirigami, have become an interdisciplinary research theme transportable from art to science, and further to engineering. Kirigami-inspired architectural design strategies allow the establishment of three-dimensional (3D) mechanical linkages with unprecedented mechanical properties. Herein, we report a crystalline zeolitic imidazolate framework (ZIF), displaying folding mechanics based on a kirigami tessellation, originated from the double-corrugation surface (DCS) pattern. Pressure- and guest-induced responses demonstrate the kirigami mechanism of the ZIF, wherein imidazolate linkers act as hinges, controlling pore dimensionality, resembling the check valve-adapted mechanical manifold. This discovery of the kirigami tessellation inside a flexible ZIF reveals foldable mechanics at the molecular level., (© 2024 Wiley‐VCH GmbH.)

Quinolone-based antibiotics commonly detected in surface, ground, and drinking water are difficult to remove and therefore pose a threat as organic contaminants of aqueous environment. We performed adsorptive removal of quinolone antibiotics, nalidixic acid and ofloxacin, using a zirconium-porphyrin-based metal-organic framework (MOF), PCN-224. PCN-224 exhibits the highest adsorption capacities for both nalidixic acid and ofloxacin among those reported for MOFs to date. The accessible metal sites of Zr metal nodes are responsible for efficient adsorptive removal. This study offers a pragmatic approach to design MOFs optimized for adsorptive removal of antibiotics.

Pesticides are chemicals widely used for agricultural industry, despite their negative impact on health and environment. Although various methods have been developed for pesticide degradation to remedy such adverse effects, conventional materials often take hours to days for complete decomposition and are difficult to recycle. Here, we demonstrate the rapid degradation of organophosphate pesticides with a Zr-based metal-organic framework (MOF), showing complete degradation within 15 min. MOFs with different active site structures (Zr node connectivity and geometry) were compared, and a porphyrin-based MOF with six-connected Zr nodes showed remarkable degradation efficiency with half-lives of a few minutes. Such a high efficiency was further confirmed in a simple flow system for several cycles. This study reveals that MOFs can be highly potent heterogeneous catalysts for organophosphate pesticide degradation, suggesting that coordination geometry of the Zr node significantly influences the catalytic activity.