Direct synthesis of mesoporous silica containing cobalt: A new strategy using a cobalt soap as a co-template

A novel approach to incorporate transition metals into porous structures is presented, which makes use of a cobalt soap in combination with the templating agent C16TMABr. An ordered mesoporous silica MCM-41 type material doped with Co is obtained after removal of the organic part by calcination. The a unit cell parameter of the cobalt containing mesoporous matrices is larger than that of pure MCM-41 and increases with the amount of cobalt present in the sample as well as the diameter of the pores. This is not observed when e.g. cobalt acetate is employed instead of the metal soap. The procedure presented establishes a new route for the incorporation of a transition metal into MCM-41 together with a tuning of the porous structure

The dehydration of SrTeO3(H2O) - a topotactic reaction for preparation of the new metastable strontium oxotellurate(IV) phase e-SrTeO3

Microcrystalline single-phase strontium oxotellurate(IV) monohydrate, SrTeO3 (H2O), was obtained by microwave-assisted hydrothermal synthesis under alkaline conditions at 180 ◦C for 30 min. A temperature of 220 ◦C and longer reaction times led to single crystal growth of this material. The crystal structure of SrTeO3 (H2O) was determined from single crystal X-ray diffraction data: P21/c, Z = 4, a = 7.7669(5), b = 7.1739(4), c = 8.3311(5)A˚ , b = 107.210(1)◦, V = 443.42(5)A˚ 3 , 1403 structure factors, 63 parameters, R[F2>2s(F2 )] = 0.0208, wR(F2 all) = 0.0516, S = 1.031. SrTeO3 (H2O) is isotypic with the homologous BaTeO3 (H2O) and is characterised by a layered assembly parallel to (100) of edge-sharing [SrO6 (H2O)] polyhedra capped on each side of the layer by trigonal-prismatic [TeO3 ] units. The cohesion of the structure is accomplished by moderate O–H ◊ ◊ ◊ O hydrogen bonding interactions between donor water molecules and acceptor O atoms of adjacent layers. In a topochemical reaction, SrTeO3 (H2O) condensates above 150 ◦C to the metastable phase e-SrTeO3 and transforms upon further heating to d-SrTeO3 . The crystal structure of e-SrTeO3 , the fifth known polymorph of this composition, was determined from combined electron microscopy and laboratory X-ray powder diffraction studies: P21/c, Z = 4, a = 6.7759(1), b = 7.2188(1), c = 8.6773(2)A˚ , b = 126.4980(7)◦, V = 341.20(18)A˚ 3 , RFobs = 0.0166, RBobs = 0.0318, Rwp = 0.0733, Goof = 1.38. The structure of e-SrTeO3 shows the same basic set-up as SrTeO3 (H2O), but the layered arrangement of the hydrous phase transforms into a framework structure after elimination of water. The structural studies of SrTeO3 (H2O) and e-SrTeO3 are complemented by thermal analysis and vibrational spectroscopic measurements.Centro de Química Inorgánic

The dimeric unit [La(H2O)4(m-PO3C6H4COOH)(m-PO2(OH)C6H4COOH)(m-PO(OH)2C6H4COOH)]2 as building block of layered hybrid material

International audienceA new hybrid organic–inorganic material with the structural formula unit [La(H2O)4(m-PO3C6H4COOH)(m-PO2(OH)C6H4COOH)(m-PO(OH)2C6H4COOH)]2 (or [La(H2O)4C21H18O15P3]2) has been synthesized under hydrothermal condition from La(NO3)3·6H2O and 3-phosphonobenzoic acid (m-PO(OH)2–C6H4–COOH) which is a rigid organic precursor possessing two types of functional groups: phosphonic acid and carboxylic acid. The two units of the produced hybrid are linked together by hydrogen bonds leading to a layered framework composing of by a repetition of inorganic and organic slices. The organic layers consist of dimeric units made of two meta-phosphono-benzoic acid linked together by hydrogen bonds involving their COOH groups. Two kinds of dimeric units are observed: PO3C6H4COOH⋯HOOCC6H4PO(OH)2, present 2 times in the structure, and PO2(OH)C6H4COOH⋯HOOCC6H4PO2(OH). The material crystallises in a monoclinic cell (C2/c (15) space group) with the following parameters: a = 42.515(4) Å, b = 7.4378(6) Å, c = 20.307(2) Å, β = 118.031(6)°, V = 5668.2(9) Å3, Z = 4, density = 1.908 g/cm3

The dimeric unit [La(H2O)4(m-PO3C6H4COOH)(m-PO2(OH)C6H4COOH)(m-PO(OH)2C6H4COOH)]2 as building block of layered hybrid material

International audienceA new hybrid organic–inorganic material with the structural formula unit [La(H2O)4(m-PO3C6H4COOH)(m-PO2(OH)C6H4COOH)(m-PO(OH)2C6H4COOH)]2 (or [La(H2O)4C21H18O15P3]2) has been synthesized under hydrothermal condition from La(NO3)3·6H2O and 3-phosphonobenzoic acid (m-PO(OH)2–C6H4–COOH) which is a rigid organic precursor possessing two types of functional groups: phosphonic acid and carboxylic acid. The two units of the produced hybrid are linked together by hydrogen bonds leading to a layered framework composing of by a repetition of inorganic and organic slices. The organic layers consist of dimeric units made of two meta-phosphono-benzoic acid linked together by hydrogen bonds involving their COOH groups. Two kinds of dimeric units are observed: PO3C6H4COOH⋯HOOCC6H4PO(OH)2, present 2 times in the structure, and PO2(OH)C6H4COOH⋯HOOCC6H4PO2(OH). The material crystallises in a monoclinic cell (C2/c (15) space group) with the following parameters: a = 42.515(4) Å, b = 7.4378(6) Å, c = 20.307(2) Å, β = 118.031(6)°, V = 5668.2(9) Å3, Z = 4, density = 1.908 g/cm3

Rigid Phosphonic Acids as Building Blocks for Crystalline Hybrid Materials

International audienceThis chapter focuses on the use of rigid phosphonic acids as precursors of hybrid materials. It first summarizes the usual methods employed for the synthesis of rigid phosphonic acid (phosphonic acid group directly bonded to an aromatic ring), which is a key stepped in designing original organic precursors and consequently original hybrids. Then, the method and experimental procedure to produce hybrid materials are summarized. The chapter illustrates hybrids obtained from polyphosphonic acid derivatives (homo‐polyfunctional precursors) and, subsequently, hetero‐polyfunctional precursors. It compares the structure of the hybrids obtained from different region isomers, and addresses the question of chemoselectivity when hetero‐polyfunctional precursors are employed as organic substrates. For some organic precursors, the consequences of changing the metallic precursor upon the structure of the hybrid are also reported. Finally, the chapter focuses on the use of a heteroaromatic unit as a rigid platform, and illustrates some recent applications

Rigid Phosphonic Acids as Building Blocks for Crystalline Hybrid Materials

International audienceThis chapter focuses on the use of rigid phosphonic acids as precursors of hybrid materials. It first summarizes the usual methods employed for the synthesis of rigid phosphonic acid (phosphonic acid group directly bonded to an aromatic ring), which is a key stepped in designing original organic precursors and consequently original hybrids. Then, the method and experimental procedure to produce hybrid materials are summarized. The chapter illustrates hybrids obtained from polyphosphonic acid derivatives (homo‐polyfunctional precursors) and, subsequently, hetero‐polyfunctional precursors. It compares the structure of the hybrids obtained from different region isomers, and addresses the question of chemoselectivity when hetero‐polyfunctional precursors are employed as organic substrates. For some organic precursors, the consequences of changing the metallic precursor upon the structure of the hybrid are also reported. Finally, the chapter focuses on the use of a heteroaromatic unit as a rigid platform, and illustrates some recent applications

m-phosphonobenzoic acid and copper(II) as precursors of helical chain and lamellar hybrid materials

International audienceA 1D helical-chain material Cu6(H2O)7(m-PO3C6H4CO2)41, characterized by a non-centrosymmetric crystal structure, and a 2D lamellar hybrid material Cu(H2O)(m-PO3C6H4CO2H) 2 have been synthesised starting from m-phosphonobenzoic acid and copper(II). The pH of the reaction media regulates the formation of either 1 or 2

Lead(II) Hybrid Materials from 3- or 4-Phosphonobenzoic Acid

International audienceThree new hybrid organic-inorganic materials Pb3(H2O)2(p-PO3C6H4CO2)2 (2), Pb6(H2O)2(p-PO3C6H4CO2)4 (3), and Pb5(p-PO3C6H4COOH)2(p-PO3C6H4CO2)2 (4) have been synthesized by hydrothermal treatment involving PbII salts and a rigid heterodifunctional precursor 4-phosphonobenzoic acid {p-PO(OH)2C6H4COOH}. The use of 3-phosphonobenzoic acid {m-PO(OH)2C6H4COOH} as another rigid organic precursor is also reported. These two organic building units possess two distinct functional groups (phosphonic acid and carboxylic acid) both having the aptitude to generate chemical bonds with a metallic precursor. The structures of the produced materials have been solved by means of single-crystal X-ray diffraction data. It was observed that the use of the 4-phosphonobenzoic acid produces the hybrids 2, 3, or 4 that possess a layered structure. In these three materials, the inorganic planes are linked together via an organic bridge. For 2, 3 and 4 the understanding of the stacking of the organic molecules within the layer, the influence of the electronic lone pair and the water molecules is discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009

m-phosphonobenzoic acid and copper(II) as precursors of helical chain and lamellar hybrid materials

International audienceA 1D helical-chain material Cu6(H2O)7(m-PO3C6H4CO2)41, characterized by a non-centrosymmetric crystal structure, and a 2D lamellar hybrid material Cu(H2O)(m-PO3C6H4CO2H) 2 have been synthesised starting from m-phosphonobenzoic acid and copper(II). The pH of the reaction media regulates the formation of either 1 or 2

Elaboration and characterization of novel polyamide-12-layered titanoniobates nanocomposites

International audienceThis article describes the synthesis and the characterization of a polyamide-12 filled with a nanostructured organic/inorganic titanoniobate hybrid material. The pristine oxide KTiNbO5 has been successfully organomodified by N-alkyl amines via an acido-basic reaction after a cationic exchange step as shown by x-ray diffraction. Transmission electron microscope study and scanning transmission electron microscope observations have been used to describe the change of morphology of the nanofillers before and after processing; the micronic aggregates were changed into single sheets and dispersed in the polymer. Thermomechanical properties of the composites have been determined, and their analyses with structure-properties models are consistent with the exfoliation of the organomodified titanoniobates