Chitin/Metal-Organic Framework Composites as Wide-Range Adsorbent.

Composites based on chitin (CH) biopolymer and metal-organic framework (MOF) microporous nanoparticles have been developed as broad-scope pollutant absorbent. Detailed characterization of the CH/MOF composites revealed that the MOF nanoparticles interacted through electrostatic forces with the CH matrix, inducing compartmentalization of the CH macropores that led to an overall surface area increase in the composites. This created a micro-, meso-, and macroporous structure that efficiently retained pollutants with a broad spectrum of different chemical natures, charges, and sizes.

Chromium Speciation in Zirconium-Based Metal-Organic Frameworks for Environmental Remediation.

Acute Cr water pollution due to anthropogenic activities is an increasing worldwide concern. The high toxicity and mobility of Cr makes it necessary to develop dual adsorbent/ion-reductive materials that are able to capture Cr and transform it efficiently into the less hazardous Cr . An accurate description of chromium speciation at the adsorbent/ion-reductive matrix is key to assessing whether Cr is completely reduced to Cr , or if its incomplete transformation has led to the stabilization of highly reactive, transient Cr species within the material.

Encapsulation of β-alanine model amino-acid in zirconium(IV) metal organic frameworks: Defect engineering to improve host guest interactions.

Metal-Organic Frameworks (MOFs) are porous coordination networks assembled through metal complexes with organic linkers. Due to their chemical versatility, these materials are being investigated for various applications including gas storage and separation, biomedicine and catalysis. The aim of this work is the encapsulation of the model β-alanine amino-acid in the nanostructured zirconium-based MOF (UiO-66) which contains the ligand HBDC (1,4-benzenedicaboxylic acid).

Thermal activation of charge carriers in ionic and electronic semiconductor β-AgVO and β-AgVO@V V O composite xerogels.

Silver vanadium oxide (SVO) and Silver Vanadium Oxide/Vanadium Oxide (SVO@VO) composite hydrogels are formed from the self-entanglement of β-AgVO nanoribbons and slightly reduced vanadium oxide (VO) (V V O) nanoribbons; respectively. Starting from randomly distributed nanoribbons within hydrogels, and after a controlled drying process, a homogeneous xerogel system containing tuneable SVO : VO ratios from 1 : 0 to 1 : 1 can be obtained. The precise nanoribbons compositional control of these composite system can serve as a tool to tune the electrical properties of the xerogels, as it has been demonstrated in this work by impedance spectroscopy (IS) experiments.

Exploring new hydrated delta type vanadium oxides for lithium intercalation.

Three hydrated double layered vanadium oxides, namely NaVO·0.8(HO), K(HO)VO and (NH)VO·0.15(HO), were obtained by using mild hydrothermal conditions.

Ionothermal Synthesis of Cadmium Coordination Polymers: Ionic Liquid Effects on the Synthesis, Structural, and Thermal Characterization.

Ionothermal synthesis is a little used method for the preparation of coordination polymers. By this method, two cadmium compounds were synthesized, , with formula Cd(ox)F(Ina) (Ina = isonicotinate) and , Cd(NO)(4,4'-Bpy) (4,4'-Bpy = 4,4'-Bipyridine). The modification of the reaction conditions has allowed to obtain as a pure phase.

Structural Transformations in the Thermal Dehydration of [Cu(bpa)(btec)(HO)] Coordination Polymer.

Reactions between pyridinic ligands such as 1,2-bis(4-pyridyl)ethane () and transition metal cations are a very widespread technique to produce extended coordination polymers such as Metal-Organic Frameworks. In combination with a second ligand these systems could present different topologies and behaviors. In this context, the use of 1,2,4,5-benzenetetracarboxylic acid () gave us a novel 2D compound, [Cu(bpa)(btec)(HO)] (), which was prepared by microwave-assisted synthesis and structurally characterized by means of single crystal X-ray diffraction.

Double role of metalloporphyrins in catalytic bioinspired supramolecular metal-organic frameworks (SMOFs).

Heterogeneous catalysts are of great interest in many industrial processes for environmental reasons and, during recent years, a great effort has been devoted to obtain metal-organic frameworks (MOFs) with improved catalytic behaviour. Few supramolecular metal-organic frameworks (SMOFs) are stable under ambient conditions and those with anchored catalysts exhibit favourable properties. However, this paper presents an innovative approach that consists of using metal nodes as both structural synthons and catalysts.

Open and closed forms of the interpenetrated [Cu(Tae)(Bpa)](NO)·nHO: magnetic properties and high pressure CO/CH gas sorption.

Two closed and one open structural forms of the interpenetrated [Cu(Tae)(Bpa)](NO)·nHO (HTae = 1,1,2,2-tetraacetylethane, Bpa = 1,2-bis(4-pyridyl)ethane) cationic coordination polymer have been synthesized. Three crystallographically related interpenetrated "ths" cationic nets encapsulate water molecules and nitrate anions giving rise to the closed structural forms of [Cu(Tae)(Bpa)](NO)·nHO. Depending on the location of water molecules and nitrate groups, two different closed forms with 5.

Catalytic Performance of a New 1D Cu(II) Coordination Polymer {Cu(NO₃)(H₂O)}(HTae)(4,4'-Bpy) for Knoevenagel Condensation.

The {Cu(NO₃)(H₂O)}(HTae)(4,4'-Bpy) (H₂Tae = 1,1,2,2-tetraacetylethane, 4,4'-Bpy = 4,4'-Dipyridyl) 1D coordination polymer has been obtained by slow evaporation. The crystal structure consists of parallel and oblique {Cu(HTae)(4,4'-Bpy)} zig-zag metal-organic chains stacked along the [100] crystallographic direction. Copper(II) ions are in octahedral coordination environment linked to two nitrogen atoms of two bridging 4,4'-Bpy and to two oxygen atoms of one HTae molecule in the equatorial plane.

Commensurate Superstructure of the {Cu(NO)(HO)}(HTae)(Bpy) Coordination Polymer: An Example of 2D Hydrogen-Bonding Networks as Magnetic Exchange Pathway.

The average and commensurate superstructures of the one-dimensional coordination polymer {Cu(NO)(HO)}(HTae)(Bpy) (HTae = 1,1,2,2-tetraacetylethane, Bpy = 4,4'-bipyridine) were determined by single-crystal X-ray diffraction, and the possible symmetry relations between the space group of the average structure and the superstructure were checked. The crystal structure consists in parallel and oblique {Cu(HTae)(Bpy)} zigzag metal-organic chains stacked along the [100] crystallographic direction. The origin of the fivefold c axis in the commensurate superstructure is ascribed to a commensurate modulation of the coordination environment of the copper atoms.

Crystal structure of K0.75[Fe(II) 3.75Fe(III) 1.25(HPO3)6]·0.5H2O, an open-framework iron phosphite with mixed-valent Fe(II)/Fe(III) ions.

Single crystals of the title compound, potassium hexa-phosphito-penta-ferrate(II,III) hemihydrate, K0.75[Fe(II) 3.75Fe(III) 1.

Heterogeneous catalytic properties of unprecedented μ-O-[FeTCPP]2 dimers (H2TCPP = meso-tetra(4-carboxyphenyl)porphyrin): an unusual superhyperfine EPR structure.

During the past few years, a great deal of effort has been devoted to the anchoring of catalysts into solid coordination networks in order to achieve heterogeneous catalysts. In this sense, an innovative approach consists in using the coordination-network synthons both as structural units and as catalysts. Regarding the latter, metalloporphyrins are suitable candidates for synthons.

Thermal response, catalytic activity, and color change of the first hybrid vanadate containing Bpe guest molecules.

Four isomorphic compounds with formula [{Co2(H2O)2(Bpe)2}(V4O12)]·4H2O·Bpe, CoBpe 1; [{CoNi(H2O)2(Bpe)2}(V4O12)]·4H2O·Bpe, CoNiBpe 2; [{Co0.6Ni1.4(H2O)2(Bpe)2}(V4O12)]·4H2O·Bpe, NiCoBpe 3; and [{Ni2(H2O)2(Bpe)2}(V4O12)]·4H2O·Bpe, NiBpe 4, have been obtained by hydrothermal synthesis.

Amine templated open-framework vanadium(III) phosphites with catalytic properties.

Four novel amine templated open-framework vanadium(III) phosphites with the formula (C(5)N(2)H(14))(0.5)[V(H(2)O)(HPO(3))(2)], 1 (C(5)N(2)H(14) = 2-methylpiperazinium), and (L)(4-x)(H(3)O)(x)[V(9)(H(2)O)(6)(HPO(3))(14-y)(HPO(4))(y)(H(2)PO(3))(3-z)(H(2)PO(4))z]·nH(2)O (2, L = cyclopentylammonium, x = 0, y = 3.5, z = 3, n = 0; , L = cyclohexylammonium, x = 1, y = 0, z = 0.

Synthesis and comparative study of Co(pym)(VO3)2 and [Co(H2O)2(VO3)2]·2H2O.

The three-dimensional Co(pym)(VO(3))(2), 1, hybrid compound, where pym is pyrimidine, has been synthesized under mild hydrothermal conditions at 120 °C. The compound has been characterized by FT-IR spectroscopy, elemental analysis, thermogravimetric measurements, thermodiffractometry, UV-Vis spectroscopy, temperature-dependent magnetic susceptibility and magnetization, and finally a study of specific heat has been performed. The crystal structure of 1 was solved using single-crystal X-ray diffraction data, taking into account that the crystals of this compound are twins of two components.

Flexible and dynamic thermal behavior of self-catenated [{Ni3(H2O)3(Bpa)4}(V6O18)]·8H2O constructed from 10-c heterometallic inorganic-organic clusters.

The hydrothermal treatment of Ni(NO(3))(2)·6H(2)O, NaVO(3), and Bpa (1,2-Di(pyridyl)ethane) (C(12)H(12)N(2)) at 120 °C during 3 days leads to green single crystals of the title compound. The single crystal X-ray diffraction reveals that [{Ni(3)(H(2)O)(3)(Bpa)(4)}(V(6)O(18))]·8H(2)O crystallizes in the monoclinic system, P2(1)/c space group, with a = 13.5536 (2), b = 19.

M(C6H16N3)2(VO3)4 as heterogeneous catalysts. Study of three new hybrid vanadates of cobalt(II), nickel(II) and copper(II) with 1-(2-aminoethyl)piperazonium.

Three new hybrid vanadates have been synthesized under hydrothermal conditions with the formula M(C(6)H(16)N(3))(2)(VO(3))(4), where M = Co(II), Ni(II) and Cu(II). The structural analyses show that the phases are isostructural and crystallize in the monoclinic space group P2(1)/c. These compounds show a two-dimensional crystal structure, with sheets composed of [VO(3)](n)(n-) chains and metal centres octahedrally coordinated, chelated by two 1-(2-aminoethyl)piperazonium ligands.