Architecting Ultra-Robust Zr(IV) Metal-Organic Framework for Energy-Efficient Desiccant Air Conditioning.

Air-conditioning systems, composed mainly of humidity control and heat reallocation units, play a pivotal role in upholding superior air quality and human well-being across diverse environments ranging from international space stations and pharmacies to granaries and cultural relic preservation sites, and to commercial and residential buildings. The adoption of sorbent water as the working pair and low-grade renewable or waste heat in adsorption-driven air-conditioning presents a state-of-the-art solution, notably for its energy efficiency and eco-friendliness vis-à-vis conventional electricity-driven vapor compression cycles. Here, we introduce a rational π-extension strategy to engineer an ultrarobust and highly porous zirconium metal-organic framework (Zr-MOF).

Modulator-Directed Counterintuitive Catenation Control for Crafting Highly Porous and Robust Metal-Organic Frameworks with Record High SO Uptake Capacity.

Sulfur dioxide (SO) is an important industrial feedstock that can be directly utilized or catalytically transformed to value-added chemicals such as sulfuric acid. The development of regenerable porous sorbents for the highly efficient storage and energy-minimal release of toxic SO operating under ambient conditions has attracted growing interest. Herein, we report the topology-guided construction of highly porous -type metal-organic frameworks (MOFs) through a counterintuitive modulator-directed catenation control approach.

Metalloporphyrinic metal-organic frameworks for enhanced photocatalytic degradation of a mustard gas simulant.

Four metalloporphyrinic metal-organic frameworks (MOFs) were successfully synthesized and exhibited enhanced activities for the photooxidation of a sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES). Among them, a Sn-porphyrin functionalized 2D MOF, namely CSLA-21-NH(Sn), showed a half-life of 1.5 min for CEES oxidation under blue LED, featuring as one of the fastest photocatalysts for CEES degradation.

Leveraging Isoreticular Principle to Elucidate the Key Role of Inherent Hydrogen-Bonding Anchoring Sites in Enhancing Water Sorption Cyclability of Zr(IV) Metal-Organic Frameworks.

Water adsorption/desorption cyclability of porous materials is a prerequisite for diverse applications, including atmospheric water harvesting (AWH), humidity autocontrol (HAC), heat pumps and chillers, and hydrolytic catalysis. However, unambiguous molecular insights into the correlation between underlying building blocks and the cyclability are still highly elusive. In this work, by taking advantage of the well-established isoreticular synthetic principle in Zr(IV) metal-organic frameworks (Zr-MOFs), we show that the inherent density of hydrogen atoms in the organic skeleton can play a key role in regulating the water sorption cyclability of MOFs.

Role of Metal-Organic Framework Topology on Thermodynamics of Polyoxometalate Encapsulation.

Polyoxometalates (POMs) are discrete anionic clusters whose rich redox properties, strong Bro̷nsted acidity, and high availability of active sites make them potent catalysts for oxidation reactions. Metal-organic frameworks (MOFs) have emerged as tunable, porous platforms to immobilize POMs, thus increasing their solution stability and catalytic activity. While POM@MOF composite materials have been widely used for a variety of applications, little is known about the thermodynamics of the encapsulation process.

Thermodynamic Insights into Phosphonate Binding in Metal-Azolate Frameworks.

Organophosphorus chemicals, including chemical warfare agents (CWAs) and insecticides, are acutely toxic materials that warrant capture and degradation. Metal-organic frameworks (MOFs) have emerged as a class of tunable, porous, crystalline materials capable of hydrolytically cleaving, and thus detoxifying, several organophosphorus nerve agents and their simulants. One such MOF is M-MFU-4l (M = metal), a bioinspired azolate framework whose metal node is composed of a variety of divalent first-row transition metals.

Chiral Reticular Chemistry: A Tailored Approach Crafting Highly Porous and Hydrolytically Robust Metal-Organic Frameworks for Intelligent Humidity Control.

Control of humidity within confined spaces is critical for maintaining air quality and human well-being, with implications for environments ranging from international space stations and pharmacies to granaries and cultural relic preservation sites. However, existing techniques rely on energy-intensive electrically driven equipment or complex temperature and humidity control (THC) systems, resulting in imprecision and inconvenience. The development of innovative techniques and materials capable of simultaneously meeting the stringent requirements of practical applications holds the key to creating intelligent and energy-efficient humidity control devices.

Rational Design and Reticulation of Infinite qbe Rod Secondary Building Units into Metal-Organic Frameworks through a Global Desymmetrization Approach for Inverse C H /C H Separation.

The development of reticular chemistry has enabled the construction of a large array of metal-organic frameworks (MOFs) with diverse net topologies and functions. However, dominating this class of materials are those built from discrete/finite secondary building units (SBUs), yet the designed synthesis of frameworks involving infinite rod-shaped SBUs remain underdeveloped. Here, by virtue of a global linker desymmetrization approach, we successfully targeted a novel Cu-MOF (Cu-ASY) incorporating infinite Cu-carboxylate rod SBUs with its structure determined by micro electron diffraction (MicroED) crystallography.

Modulator-Dependent Dynamics Synergistically Enabled Record SO Uptake in Zr(IV) Metal-Organic Frameworks Based on Pyrene-Cored Molecular Quadripod Ligand.

Developing innovative porous solid sorbents for the capture and storage of toxic SO is crucial for energy-efficient transportation and subsequent processing. Nonetheless, the quest for high-performance SO sorbents, characterized by exceptional uptake capacity, minimal regeneration energy requirements, and outstanding recyclability under ambient conditions, remains a significant challenge. In this study, we present the design of a unique tertiary amine-embedded, pyrene-based quadripod-shaped ligand.

Reticular Chemistry in Its Chiral Form: Axially Chiral Zr(IV)-Spiro Metal-Organic Framework as a Case Study.

The interplay of primary organic ligands and inorganic secondary building units (SBUs) has led to a continual boom of reticular chemistry, particularly metal-organic frameworks (MOFs). Subtle variations of organic ligands can have a significant impact on the ultimate structural topology and consequently, the material's function. However, the role of ligand chirality in reticular chemistry has rarely been explored.

Expanding Linker Dimensionality in Metal-organic Frameworks for sub-Ångstrom Pore Control for Separation Applications.

Metal-organic frameworks (MOFs) are a class of porous materials with high surface areas, which are acquiring rapid attention on an exponential basis. A significant characteristic of MOFs is their ability to act as adsorbents to selectively separate component mixtures of similar size, thereby addressing the technological need for an alternative approach to conventional distillation methods. Recently, MOFs comprising a 3-Dimensional (3D) linker have shown outstanding capabilities for difficult separations compared to the parent 2-Dimensional (2D) analogue.

Programmed Polarizability Engineering in a Cyclen-Based Cubic Zr(IV) Metal-Organic Framework to Boost Xe/Kr Separation.

Efficient separation of xenon (Xe) and krypton (Kr) mixtures through vacuum swing adsorption (VSA) is considered the most attractive route to reduce energy consumption, but discriminating between these two gases is difficult due to their similar properties. In this work, we report a cubic zirconium-based MOF (Zr-MOF) platform, denoted as NU-1107, capable of achieving selective separation of Xe/Kr by post-synthetically engineering framework polarizability in a programmable manner. Specifically, the tetratopic linkers in NU-1107 feature tetradentate cyclen cores that are capable of chelating a variety of transition-metal ions, affording a sequence of metal-docked cationic isostructural Zr-MOFs.

Tröger's Base Chemistry in Solution and in Zr(IV)-Based Metal-Organic Frameworks.

Tröger's base (TB) and its derivatives have been studied extensively due to their unique concave shape stemming from the endomethylene strap. However, the strap-clipped TB chemistry has been largely overlooked in metal-organic framework (MOF) solids, leading to a gap in our knowledge within this field. In this work, we report the in situ strap elimination of a carboxylate-carrying TB in the presence of formic acid, both in solution and in Zr(IV)-based MOFs.

Creating Optimal Pockets in a Clathrochelate-Based Metal-Organic Framework for Gas Adsorption and Separation: Experimental and Computational Studies.

The rational design and synthesis of robust metal-organic frameworks (MOFs) based on novel organic building blocks are fundamental aspects of reticular chemistry. Beyond simply fabricating new organic linkers, however, it is important to elucidate structure-property relationships at the molecular level to develop high-performing materials. In this work, we successfully targeted a highly porous and robust cage-type MOF (NU-200) with an -derived topology through the deliberate assembly of a cyclohexane-functionalized iron(II)-clathrochelate-based -benzenedicarboxylate linker with a Cu(CO) secondary building unit (SBU).

Leveraging Chiral Zr(IV)-Based Metal-Organic Frameworks To Elucidate Catalytically Active Rh Species in Asymmetric Hydrogenation Reactions.

One of the most widely employed strategies to produce chiral molecules involves the asymmetric hydrogenation of functionalized olefins using rhodium catalysts. Despite their excellent performance, the exact identity of the active Rh species is still ambiguous as each site may plausibly feature one or two phosphorus ligands. In this work, we used a sequential postsynthetic modification approach to successfully incorporate single-site Rh species into a zirconium-based metal-organic framework comprised of chiral spinol-based ligands.

Water Sorption Evolution Enabled by Reticular Construction of Zirconium Metal-Organic Frameworks Based on a Unique [2.2]Paracyclophane Scaffold.

Water vapor sorption by metal-organic frameworks (MOFs) has gathered significant interest because of its prominent potential in many applications such as moisture harvesting, dehumidification, heat pump regulation, and hydrolysis catalysis. However, the reticular design and exploration of robust and high-performing Zr-MOFs for such purposes remains a sought-after endeavor. In this work, we present the deployment of reticular chemistry to target a series of robust Zr-MOFs based on a unique [2.

Highly Specific Coordination-Driven Self-Assembly of 2D Heterometallic Metal-Organic Frameworks with Unprecedented Johnson-type () Nonanuclear Zr-Oxocarboxylate Clusters.

The quest for new and unique polynuclear metal-oxocarboxylate clusters has led to a continual boom of highly connected and robust metal-organic frameworks (MOFs) with intriguing properties. In this work, by virtue of a highly specific coordination-driven cluster rearrangement process of a presynthesized trinuclear zirconocene-based tripodal metallo-pyridine ligand, we realized the preparation of the first two 2D heterometallic MOFs incorporating unprecedented Johnson-type () nonanuclear Zr-oxocarboxylate clusters, as unambiguously uncovered by single-crystal X-ray crystallography. The resultant two charged frameworks feature counteranion-dependent 3,6-c kgd (JMOF-1) and 3,12-c 3,12L4 (JMOF-2) nets that are formed by octahedral and hexagonal prismatic Zr molecular building blocks (MBBs), respectively.

Stabilization of Photocatalytically Active Uranyl Species in a Uranyl-Organic Framework for Heterogeneous Alkane Fluorination Driven by Visible Light.

When photoactivated, the uranyl ion is a powerful oxidant capable of abstracting hydrogen atoms from nonactivated C-H bonds. However, the highly reactive singly reduced [UO] intermediate is unstable with respect to disproportionation to the uranyl dication and insoluble tetravalent uranium phases, which limits the usage of uranyl ions as robust photocatalysts. Herein, we demonstrate that photoactivated uranyl ions can be stabilized by immobilizing and separating them spatially in a uranyl-organic framework heterogeneous catalyst, NU-1301.