Crystalline metal-organic frameworks (MOFs) are formed by reticular synthesis, which creates strong bonds between inorganic and organic units. Careful selection of MOF constituents can yield crystals of ultrahigh porosity and high thermal and chemical stability. These characteristics allow the interior of MOFs to be chemically altered for use in gas separation, gas storage, and catalysis, among other applications. The precision commonly exercised in their chemical modification and the ability to expand their metrics without changing the underlying topology have not been achieved with other solids. MOFs whose chemical composition and shape of building units can be multiply varied within a particular structure already exist and may lead to materials that offer a synergistic combination of properties.

The Chemistry and Applications of Metal-Organic Frameworks

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Metal–organic frameworks (MOFs) display a wide range of luminescent behaviors resulting from the multifaceted nature of their structure. In this critical review we discuss the origins of MOF luminosity, which include the linker, the coordinated metal ions, antenna effects, excimer and exciplex formation, and guest molecules. The literature describing these effects is comprehensively surveyed, including a categorization of each report according to the type of luminescence observed. Finally, we discuss potential applications of luminescent MOFs. This review will be of interest to researchers and synthetic chemists attempting to design luminescent MOFs, and those engaged in the extension of MOFs to applications such as chemical, biological, and radiation detection, medical imaging, and electro-optical devices (141 references).

Luminescent Metal–Organic Frameworks

2.2. MOFs with Metal Active Sites 4614 2.2.1. Early Studies 4614 2.2.2. Hydrogenation Reactions 4618 2.2.3. Oxidation of Organic Substrates 4620 2.2.4. CO Oxidation to CO2 4626 2.2.5. Phototocatalysis by MOFs 4627 2.2.6. Carbonyl Cyanosilylation 4630 2.2.7. Hydrodesulfurization 4631 2.2.8. Other Reactions 4632 2.3. MOFs with Reactive Functional Groups 4634 2.4. MOFs as Host Matrices or Nanometric Reaction Cavities 4636

Engineering Metal Organic Frameworks for Heterogeneous Catalysis

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Metal–Organic Frameworks and Self-Assembled Supramolecular Coordination Complexes: Comparing and Contrasting the Design, Synthesis, and Functionality of Metal–Organic Materials

A series of remarkable crystalline compounds [Cu2(BTC)4/3(H2O)2]6[HnXM12O40]·(C4H12N)2 (X = Si, Ge, P, As; M = W, Mo) were obtained from the simple one-step hydrothermal reaction of copper nitrate, benzentricaboxylate (BTC), and different Keggin polyoxometalates (POMs). In these compounds, the catalytically active Keggin polyanions were alternately arrayed as noncoordinating guests in the cuboctahedral cages of a Cu-BTC-based metal−organic framework (MOF) host matrix. X-ray crystallographic analyses, TG, FT-IR, UV−vis, N2 adsorption studies, and acid−base titration demonstrated their high stability and toleration for thermal and acid−base conditions. No POM leaching or framework decomposition was observed in our study. The representative acid catalytic performance of a compound containing PW12 species was assessed through the hydrolysis of esters in excess water, which showed high catalytic activity and can be used repeatedly without activity loss. Moreover, catalytic selectivity, which is dependent on th...

Highly stable crystalline catalysts based on a microporous metal-organic framework and polyoxometalates.

The Dawson anion P2W18O626− has been used as a noncoordinating polyoxoanion template for the construction of two metal−organic frameworks, namely, [M2(bpy)3(H2O)2(ox)][P2W18O62]2(H2-bpy)·nH2O (M = Co(II), n = 3 (1); M = Ni(II), n = 2 (2)) (bpy = 4,4′-bipyridine; ox = C2O42−). Single-crystal X-ray analysis reveals that both of the structures exhibit 3D host frameworks constructed from the oxalate-bridged binuclear superoctahedron secondary building units (SBUs) and bpy linkers and the voids of which are occupied by Dawson anions, guest bpy, and water molecules. Magnetic studies reveal that there are antiferromagnetic exchange interactions among the transition-metal centers in compounds 1 and 2. Furthermore, a compound 1-modified carbon paste electrode (1-CPE) displays good electrocatalytic activity toward the reduction of nitrite.

Two Dawson-templated three-dimensional metal-organic frameworks based on oxalate-bridged binuclear cobalt(II)/Nickel(II) SBUs and Bpy linkers.

Two novel organic−inorganic hybrid compounds based on Anderson-type polyoxoanions, [Cu2(bpy)2(μ-ox)][Al(OH)7Mo6O17] (1) and [Cu2(bpy)2(μ-ox)][Cr(OH)7Mo6O17] (2), have been synthesized and characterized by elemental analyses, IR, and X-ray powder diffraction. The crystal structures of 1 and 2 have been established by single-crystal X-ray diffraction, which reveals the presence of 1D chains constructed of alternating Anderson-type polyoxoanions and oxalato-bridged dinuclear copper complexes for both compounds and extensive hydrogen bonding that plays an important role in the formation of the 3D supramolecular network structures of 1 and 2. To elucidate the electronic properties and magnetic properties of the metal ions (Cu2+ or Cu2+ and Cr3+), EPR studies and magnetic susceptibility studies have been performed, respectively. The results are consistent with the structural feature of these compounds.

Organic-inorganic hybrids constructed of anderson-type polyoxoanions and oxalato-bridged dinuclear copper complexes.

A series of organic–inorganic hybrid compounds, K2H7[{Ln(PW11O39)2}{Cu2(bpy)2(μ-ox)}]·xH2O (Ln = La, x≈ 18 (1); Ln = Pr, x≈ 18 (2); Ln = Eu, x≈ 16 (3); Ln = Gd, x≈ 22 (4); Ln = Yb, x≈ 19 (5); bpy = 2,2′-bipyridine and ox = oxalate), have been isolated by the conventional solution method. Single-crystal X-ray diffraction studies reveal that compounds 1–5 are isomorphic and consist of one-dimensional chains, which are constructed by alternating bis(undecatungstophosphate) lanthanates [Ln(PW11O39)2]11− and dinuclear copper(II)–oxalate complexes [Cu2(bpy)2(μ-ox)]2+. π–π interactions of the bpy ligands from adjacent chains lead to their three-dimensional structures. An analogue of potassium K2H9[{K(PW11O39)2}{Cu2(bpy)2(μ-ox)}]·∼20.5H2O (6) has also been obtained. The syntheses and structures of these compounds are reported here. Magnetic properties of 1, 2 and 3 are discussed as well. Attempts to crystallize similar compounds containing Co(II) and Ni(II) were unsuccessful.

Organic-inorganic hybrids assembled by bis(undecatungstophosphate) lanthanates and dinuclear copper(II)-oxalate complexes.

Organic-inorganic hybrid polyoxometalate (POM) compounds are a subset of materials with unique structures and physical/chemical properties. The combination of metal-organic coordination complexes with classical POMs not only provides a powerful way to gain multifarious new compounds but also affords a new method to modify and functionalize POMs. In parallel with the many reports on the synthesis and structure of new hybrid POM compounds, the application of these compounds for heterogeneous catalysis has also attracted considerable attention. The hybrid POM compounds show noteworthy catalytic performance in acid, oxidation, and even in asymmetric catalytic reactions. This review summarizes the design and synthesis of organic-inorganic hybrid POM compounds and particularly highlights their recent progress in heterogeneous catalysis.

https://www.mdpi.com/1996-1944/8/4/1545/pdf

Yuanhang Ren

Papers

Highly stable crystalline catalysts based on a microporous metal-organic framework and polyoxometalates.

Two Dawson-templated three-dimensional metal-organic frameworks based on oxalate-bridged binuclear cobalt(II)/Nickel(II) SBUs and Bpy linkers.

Organic-inorganic hybrids constructed of anderson-type polyoxoanions and oxalato-bridged dinuclear copper complexes.

Organic-inorganic hybrids assembled by bis(undecatungstophosphate) lanthanates and dinuclear copper(II)-oxalate complexes.

Heterogeneous Catalysis of Polyoxometalate Based Organic–Inorganic Hybrids