http://pubs.acs.org/doi/pdfplus/10.1021/cr300162p

Deep Eutectic Solvents (DESs) and Their Applications

Synthesis of metal-organic frameworks (MOFs): routes to various MOF topologies, morphologies, and composites.

A simple one-step NaCl-assisted microwave-solvothermal method has been developed for the preparation of monodisperse α-Fe2O3 mesoporous microspheres. In this approach, Fe(NO3)3 · 9H2O is used as the iron source, and polyvinylpyrrolidone (PVP) acts as a surfactant in the presence of NaCl in mixed solvents of H2O and ethanol. Under the present experimental conditions, monodisperse α-Fe2O3 mesoporous microspheres can form via oriented attachment of α-Fe2O3 nanocrystals. One of the advantages of this method is that the size of α-Fe2O3 mesoporous microspheres can be adjusted in the range from ca. 170 to ca. 260 nm by changing the experimental parameters. High photocatalytic activities in the degradation of salicylic acid are observed for α-Fe2O3 mesoporous microspheres with different specific surface areas.

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Monodisperse α-Fe2O3 Mesoporous Microspheres: One-Step NaCl-Assisted Microwave-Solvothermal Preparation, Size Control and Photocatalytic Property

The purpose of this critical review is to give a representative and comprehensive overview of the arising developments in the field of magnetic metal–organic frameworks, in particular those containing cobalt(II). We examine the diversity of magnetic exchange interactions between nearest-neighbour moment carriers, covering from dimers to oligomers and discuss their implications in infinite chains, layers and networks, having a variety of topologies. We progress to the different forms of short-range magnetic ordering, giving rise to single-molecule-magnets and single-chain-magnets, to long-range ordering of two- and three-dimensional networks (323 references).

Magnetic metal-organic frameworks.

Encapsulating guest molecules inside host structures ranging from soft, flexible enzymes to rigid, porous zeolites has led to developments in many areas, including catalysis, sensing and separation. This Review highlights how metal–organic frameworks — materials formed by linking metal centres with organic ligands — can combine softness with regularity to produce dynamic, yet crystalline, structures that may prove useful for a range of applications.
 The field of host–guest complexation is intensely attractive from diverse perspectives, including materials science, chemistry and biology. The uptake and encapsulation of guest species by host frameworks are being investigated for a wide variety of purposes, including separation and storage using zeolites, and recognition and sensing by enzymes in solution. Here we focus on the concept of the cooperative integration of 'softness' and 'regularity'. Recent developments on porous coordination polymers (or metal–organic frameworks) have provided the inherent properties that combine these features. Such soft porous crystals exhibit dynamic frameworks that are able to respond to external stimuli such as light, electric fields or the presence of particular species, but they are also crystalline and can change their channels reversibly while retaining high regularity. We discuss the relationship between the structures and properties of these materials in view of their practical applications.

Soft porous crystals

The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time

The hydrothermal synthesis of zeolites: precursors, intermediates and reaction mechanism

The prediction and synthesis of new crystal structures enable the targeted preparation of materials with desired properties. Among porous solids, this has been achieved for metal-organic frameworks ...

/pdf/a-zeolite-family-with-expanding-structural-complexity-and-35nu2rn7ky.pdf

A zeolite family with expanding structural complexity and embedded isoreticular structures

SYNTHETIC alumino-silicate zeolites are widely used in the petrochemical industry as catalysts. In particular the few with multidimensional channel systems are highly valued, as they permit more complex chemistry within the pores and are less prone to deactivation through coking than are one-dimensional systems. Materials with a high silica content have improved stability towards heat in the presence or absence of steam (conditions frequently encountered in catalytic processes). NU-87 is a recently synthesized, medium-pore high-silica zeolite1 with promising catalytic properties2. Here we describe its framework topology as deduced by electron diffraction. The data were refined by comparison with X-ray powder diffraction patterns using geometric criteria, lattice-energy minimization and Rietveld refinement. The structure is unique in having a two-dimensional channel system defined by rings of 10 oxygen atoms within the framework (10-ring windows). Adjacent one-dimensional 10-ring channels are linked by short 12-ring channels to create a two-dimensional network, but access to these bridging sections is possible only via the 10-ring windows. Although the past two decades have seen considerable advances in the synthesis of novel zeolite frameworks3, NU-87 is the first high-silica 10-ring zeolite with intersecting channels to be synthesized since the industrially important ZSM-54 and ZSM-115 (both of which have three-dimensional channel systems) nearly 20 years ago.

Paul A. Cox

Papers

The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time

The hydrothermal synthesis of zeolites: precursors, intermediates and reaction mechanism

A zeolite family with expanding structural complexity and embedded isoreticular structures

The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time

Structure of the two-dimensional medium-pore high-silica zeolite NU-87