A series of MOFs based on a triangular tri(4-pyridylphenyl)amine ligand combined with carboxylate or nitrate auxiliary ligands

A series of new metal–organic frameworks based on a triangular tri(4-pyridylphenyl)amine (TPPA) ligand that possess novel structures and features have been successfully synthesized and structurally characterized in detail.

Metal–organic frameworks catalyzed C–C and C–heteroatom coupling reactions

This critical review aims to illustrate the recent developments in the field of C–C and C–X (X = O, N) coupling reactions promoted by metal–organic frameworks.

Immobilization of polyoxometalates in the Zr-based metal organic framework UiO-67

We report the successful synthesis of several POM@UiO-67 composites and their characterization by a panel of complementary techniques.

Using Hansen solubility parameters to study the encapsulation of caffeine in MOFs

In this work the application of Hansen solubility parameters in the study of caffeine encapsulation in metal organic frameworks (MOFs) has been initiated.

Removal of hazardous organics from water using metal-organic frameworks (MOFs): plausible mechanisms for selective adsorptions

Provision of clean water is one of the most important issues worldwide because of continuing economic development and the steady increase in the global population. However, clean water resources are decreasing everyday, because of contamination with various pollutants including organic chemicals. Pharmaceutical and personal care products, herbicides/pesticides, dyes, phenolics, and aromatics (from sources such as spilled oil) are typical organics that should be removed from water. Because of their huge porosities, designable pore structures, and facile modification, metal-organic frameworks (MOFs) are used in various adsorption, separation, storage, and delivery applications. In this review, the adsorptive purifications of contaminated water with MOFs are discussed, in order to understand possible applications of MOFs in clean water provision. More importantly, plausible adsorption or interaction mechanisms and selective adsorptions are summarized. The mechanisms of interactions such as electrostatic interaction, acid-base interaction, hydrogen bonding, π-π stacking/interaction, and hydrophobic interaction are discussed for the selective adsorption of organics over MOFs. The adsorption mechanisms will be very helpful not only for understanding adsorptions but also for applications of adsorptions in selective removal, storage, delivery and so on.

Carbon nanodots functional MOFs composites by a stepwise synthetic approach: enhanced H2 storage and fluorescent sensing

The carbon nanodots functional UMCM-1 composites (Cdots@UMCM-1a) were first synthesized by a stepwise synthetic approach, which enhanced H₂ storage capacity and exhibited highly fluorescent sensing for nitroaromatic explosives.

Magnetically separable palladium nanocluster supported iron based metal–organic framework (MIL-88B) catalyst in efficient hydrogenation reactions

A magnetically separable palladium nanocluster (Pd NCs) supported iron based metal–organic framework, Pd@MIL-88B catalyst for enhanced catalytic activity towards the reduction of 4-nitrophenol.

Metal/metal oxide nanostructures derived from metal–organic frameworks

MOFs-derived micro/nanostructures have important potential applications. In this review, we describe the use of MOFs as templates in the synthesis of metal/metal oxide micro/nanostructures and composite materials. The applications of the derived materials are also reviewed.

Different acidity and additive effects of zirconium metal–organic frameworks as catalysts for cyanosilylation

Both hydrous and anhydrous UiO-66 MOFs are heterogeneous and recyclable catalysts for aldehyde cyanosilylation owing to Brønsted and Lewis acidity, respectively, and pyridine can enhance the activity, instead of poisoning the catalysts.

Photonic metal-organic framework composite spheres: a new kind of optical material with self-reporting molecular recognition

Exploiting metal-organic framework (MOF) materials as novel building blocks to construct superstructures with extended and enhanced functions represents a big challenge. In biological systems, the ordering of many components is not achieved by interaction of the components with each other, but by interaction of each component with the host protein which provides a matrix to support the entire assembly. Inspired by biological systems, in this work, a general strategy for efficient spatial arrangement of MOF materials was developed by using spherical colloidal crystals as host matrices, affording a new class of highly tunable MOF composite spheres with a series of distinctive properties. It was found that the synergetic combination of the unique features of both MOF and photonic colloidal crystal imparted these hierarchically structured spheres intrinsic optical properties, specific molecular recognition with self-reporting signalling, derivatization capability, and anisotropy. More importantly, the unique photonic band-gap structure integrated in these composite spheres provides a more convenient means to manipulate the photophysical and photochemical behaviour of the trapped guest molecules in MOF nanocavities.

Magnetic metal-organic frameworks: γ-Fe2O3@MOFs via confined in situ pyrolysis method for drug delivery

A general one-step in situ pyrolysis route for the construction of metal-organic frameworks encapsulating superparamagnetic γ-Fe2O3NPs dispersed in the confined cavities of MOFs homogeneously is described. The integration of γ-Fe2O3 NPs or clusters into MOFs can endow these porous materials with superparamagnetic element. By the combination of the thermal stability of MOFs and pyrolysis of metal triacetylacetonate complex at matched conditions, the porous structure of MOFs are well maintained while the size-induced superparamagnetic property of nano γ-Fe2O3 is obtained. As a proof of concept, both the γ- Fe2O3@ZIF-8 and γ-Fe2O3@MIL-53(Al) were successfully prepared, and the latter was chosen to demonstrate its potential drug delivery as a magnetic MOF.

Enhancing optical absorption of metal-organic frameworks for improved visible light photocatalysis

NH2-MIL-125(Ti) has been post-synthetically functionalized with dye-like molecular fragments. The new material (methyl red-MIL-125(Ti)) exhibits improved light absorption over a wide range of the visible spectrum, and shows enhanced photocatalytic oxidation activity under visible light illumination. The consequences of functionalization and the bottlenecks in MOF photochemistry are studied in detail.

Using functional nano- and microparticles for the preparation of metal-organic framework composites with novel properties

A critical materials challenge over the next quarter century is the sustainable use and management of the world's natural resources, particularly the scarcest of them. Chemistry's ability to get more from less is epitomized by porous coordination polymers, also known as metal-organic frameworks (MOFs), which use a minimum amount of material to build maximum surface areas with fine control over pore size. Their large specific surface area and tunable porosity make MOFs useful for applications including small-molecule sensing, separation, catalysis, and storage and release of molecules of interest. Proof-of-concept projects have demonstrated their potential for environmental applications such as carbon separation and capture, water purification, carcinogen sequestration, byproduct separation, and resource recovery. To translate these from the laboratory into devices for actual use, however, will require synthesis of MOFs with new functionality and structure. This Account summarizes recent progress in the use of nano- and microparticles to control the function, location, and 3D structure of MOFs during MOF self-assembly, creating novel, hybrid, multifunctional, ultraporous materials as a first step towards creating MOF-based devices. The use of preformed ceramic, metallic, semiconductive, or polymeric particles allows the particle preparation process to be completely independent of the MOF synthesis, incorporating nucleating, luminescent, magnetic, catalytic, or templating particles into the MOF structure. We discuss success in combining functional nanoparticles and porous crystals for applications including molecular sieve detectors, repositionable and highly sensitive sensors, pollutant-sequestering materials, microfluidic microcarriers, drug-delivery materials, separators, and size-selective catalysts. In sections within the Account, we describe how functional particles can be used for (1) heterogeneous nucleation (seeding) of MOFs, (2) preparation of framework composites with novel properties, (3) MOF positioning on a substrate (patterning), and (4) synthesis of MOFs with novel architectures.

Metal–organic frameworks as heterogeneous photocatalysts: advantages and challenges

The use of metal organic frameworks as photocatalysts is critically reviewed and their main advantages and challenges are evaluated.

Applications of metal–organic frameworks in heterogeneous supramolecular catalysis

The contributions of MOFs to the field of heterogeneous supramolecular catalysis are comprehensively reviewed with regard to active sites, selectivity, as well as host–guest chemistry.

Metal−organic framework encapsulated Pd nanoparticles: towards advanced heterogeneous catalysts

Palladium precursors were encapsulated through ligand design prior to the MOF assembly, achieving uniformly distributed Pd NPs inside the cavities of MOFs. The embedded Pd NPs exhibited significantly improved catalytic efficiencies as compared to those synthesized by traditional impregnation method, due to the nano-confinement and electron-donation effects offered by MOFs.

Alkaline earth metal-based metal–organic framework: hydrothermal synthesis, X-ray structure and heterogeneously catalyzed Claisen–Schmidt reaction

Two alkaline earth metal based carboxylate framework systems, [Mg(HL)(H₂O)₂]_n (1) and [Ca(H₂L)₂]_n (2) (H₃L = chelidamic acid) have been hydrothermally synthesized and characterized. Both compound 1 and its dehydrated species heterogeneously catalyze Claisen–Schmidt reaction.

Immobilization of Co-containing polyoxometalates in MIL-101(Cr): structural integrity versus chemical transformation

Complementary techniques evidenced the integrity or the evolution of polyoxometalates inside the nanocages of the metal organic framework MIL-101(Cr).

Metal–organic frameworks as solid catalysts for the synthesis of nitrogen-containing heterocycles

This Critical Review summarizes the recent developments in the use of metal–organic frameworks as catalysts for the synthesis of nitrogen-containing heterocycles.

Recent advances in porous polyoxometalate-based metal–organic framework materials

POM-based MOF materials, which combine the advantages of both POMs and MOFs, have received increasing attention. In this review, we present the recent developments in porous POM-based MOF materials for the first time, including their classification, synthesis strategies and applications, especially in the field of catalysis.

Porphyrins functionalized by quaternary pyridinium units

In this review, free-base and metalloporphyrins, functionalized on meso-positions by quaternary pyridinium units, also referred to as cationic porphyrins, are presented. The article consists of five parts. In the first part free-base porphyrins are described, especially taking account on generation of singlet oxygen; next parts concern metalloporphyrins. The second and third parts deal with zinc and manganese porphyrins, respectively; in the fourth part copper, palladium, and platinum porphyrins are presented. In the fifth part, describing porphyrins with various metal ions an attention is paid to porphyrin metal-organic frameworks (MOFs) and metal-organic materials (MOMs) in which metalloporphyrins are immobilized; syntheses and characterization of obtained products are shown.

Stabilization of graphene quantum dots (GQDs) by encapsulation inside zeolitic imidazolate framework nanocrystals for photoluminescence tuning

Luminescent graphene quantum dots (GQDs) are encapsulated and stabilized in Zeolitic Imidazolate Framework (ZIF-8) nanocrystals. The GQDs are well confined due to the adsorption on the growing face of the ZIF-8 nanocrystals and have a profound effect on the shape of the nanocrystals from rhombic dodecahedron to spherical. Stabilizing GQDs inside the ZIF-8 nanocrystals results in tailoring of the photoluminescence emission (ca. 32 nm, bathochromic shift) of the GQD@ZIF-8 nanocrystal composite even after 3 months of aging under normal laboratory conditions. Also the water adsorption (at STP) capacity increased for the GQD@ZIF-8 composite as compared to the pristine ZIF-8.

Strategies for Creating Active Sites in MOFs

This chapter presents a general overview of the main properties of MOFs that make them very appealing for applications in heterogeneous catalysis. Great efforts have been directed in the last decade to study the potential of MOFs in catalysis. We will now see what is behind this “MOF rush”. Next, we will present some general considerations that should be taken into account when planning the use of MOFs as heterogeneous catalysts, such as stability, recovery and reusability. And finally, we will review the different strategies that can be used to introduce the desired catalytic centers into the MOFs. We will show how it is possible by using these strategies to engineer the material for catalysis, and to fine tune the properties of the MOF to influence the catalytic performance.