Hydrothermal synthesis and structural characterization of a novel P-V-O layered compound [H(2)en](2)[H3O](6)[Co(H2O)(2)(VO)(8)(OH)(4)(PO4)8]

A new compound [H(2)en](2)[H3O](6)[Co(H2O)(2)(VO)(8)(OH)(4)(PO4)(8)] has been hydrothermally synthesized. Single crystal X-ray analysis indicates that this compound crystallizes in a monoclinic system, space group P2(1)/n with a=1.438 5(3) nm, b=1.012 2(2) nm, c=1.832 5(4) nm, beta=90.21degrees, V=2.668 2 (9) nm(3), Z = 2, D-c = 2.112 g/cm(3), R = 0.055, wR = 0.149 7, S = 1.037. The structure of [H(2)en](2)[H3O](6)[Co(H2O)(2)(VO)(8)(OH)(4)(PO4)(8)] is characterized by P-V-O layers constructed by [(VO)4 (OH)(2)(PO4)(4)](6-) non-symmetric units. The P-V-O layers are pillared by [Co(H2O)(2)](2+) group, resulting in the channels within which the protonated diaminoethane and H3O+ are located.

Hydrothermal synthesis and crystal structure of a layered inner-tunnel compound [(CuI)(2)(o-phen)(2)]

A layered inner-tunnel supramolecular compound 1, [(CuI)(2)(o-phen)(2)], was hydrothermally synthesized and structurally characterized by X-ray crystal diffraction. It crystallizes in triclinic system, space group P (1) over bar with a=0.7759(2) nm, b=0.9070(2) rim, c=0.91894(10) rim, alpha=96.306(14)degrees, beta=104.567(16)degrees, gamma=109.421(19)degrees, V=0.5768(2) nm(3), Z=1, R=0.0348, omegaR=0.0920.

Carbon ceramic electrodes bulk-modified with nanoparticles of ferrocenebutyrate-intercalated Mg-Al layered double hydroxide

Ferrocenebutyrate-intercalated layered double hydroxide (FcLDH) was prepared by the coprecipitation method and characterized by PXRD, FTIR, TEM and elemental analysis. FcLDH nanoparticles in deionized water were deposited onto the surface of graphite powder to yield graphite powder-supported FcLDH, which was subsequently dispersed into methyltrimethoxysilane-derived gels to fabricate surface-renewable, stable, rigid carbon ceramic electrodes containing the electroactive ferrocenyl group. Cyclic voltammetric study revealed that peak currents of the FcLDH-modified electrode were diffusion-con trolled in 0.1 mol l(-1) KCl aqueous solution. In addition, the formal potential of the modified electrode is related to the activity of chloride ion with a Nernst slope of 56 mV per decade.

Structural phase transition in the layered perovskite compound BaTb2Mn2O7

A distorted layered perovskite compound BaTb2Mn2O7 was synthesized by the solid state reaction in pure argon. There is a structural phase transition in the BaTb2Mn2O7 compound. The phase transition was characterized by the DSC and high temperature Xray diffraction. The heat capacity of BaTb2Mn2O7 was calculated. The thermal anomaly corresponding to the phase transition was observed at about 740K. The lattice parameters were calculated by the CELL program for BaTb2Mn2O7, It has Tb-type orthorhombic symmetry with a = 0.3908 nm, b = 0.3866 nm, c = 2.0163 nm, and space group Immm at room temperature. With the increase of temperature, the lattice parameters gradually increase until 673K. From 723K to 973K, the compound translates to tetragonal with a = 0.39078 nm, c = 2.0277 nm and S.G. I4/mmm. This result is fairly in accordance with that of heat capacity.

Preparation, characterization and photophysical properties of layered zirconium bis(monohydrogenphosphate) intercalated with rare earth complexes

Two kinds of rare earth (RE) complexes were intercalated into zirconium bis(monohydrogenphosphate) (alpha -ZrP) by exchanging the RE complexes into the p-methyoxyaniline (PMA) preintercalated compound Zr(O3POH)(2). 2PMA (alpha -ZrP . 2PMA). Powder X-ray diffraction patterns reveal that Eu(DBM)(3)phen (DBM: dibenzoylmethane, phen: 1,10-phenanthroline) and Tb(AA)(3)phen (AA: acetylacetone) intercalated into alpha -ZrP . 2PMA. This was confirmed by the UV-visible spectra of both the RE complexes and the assemblies. At the same time, the assemblies have better luminescent properties, and the fluorescent lifetimes of RE3+ in the excited state in the assemblies are much longer than those in the complexes. The stabilities of the assemblies under UV radiation are much better than those of the RE complexes.

Preparation and characterization of layered compound zirconium bis(monohydrogenphosphate)intercalated with rare earth complex

Layered compound zirconium bis(monohydrogenphosphate)(alpha-ZrP) intercalated with rare earth complex Eu(DBM)(3)phen was prepared. The pre-intercalation of p-methoxyaniline into alpha-ZrP makes the interlayer separation large enough to exchange PMA with europium complex, thus, the luminescent assembly was prepared. This was confirmed by X-ray diffraction, UV-visible spectra and elemental analysis. The fluorescence spectra and lifetime of the assembly were also presented.

Hydrothermal synthesis and crystal structure of a novel layered compound [Ni(C10H8N2)(2)V3O8.5]

A novel layered compound, [Ni(C10H8N2)(2)V3O8.5], was hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. The compound crystallizes in monoclinic system, space group P21/c with a = 1.551 8(3) nm, b = 1.476 1(3) nm, c = 1.048 3(2) nm, beta = 92.02(3), V = 2.399 8(8) nm(3), Z = 4, R = 0. 046 7, wR(2) = 0. 085 9.

Synthesis and characterization of a new layered zinc phosphate: (C3H4N2)(3)Zn-4(HPO4)(PO4)(2) with imidazole coordinating to Zn atoms

A new two-dimensional hybrid zinc phosphate with electro-neutral open-framework has been hydrothermally synthesized by using imidazole as a structure-directing agent, whose structure is characterized with 3-, 4-, 5, and 12-ring layers and coordination bonds between imidazole groups and zinc atoms, resulting in primary building units of ZnO2N2 and ZnO3N.

Study of physicochemical properties and active oxygen in structures of layered mixed La4BaCu5-xMxO13+lambda (M = Mn, Co)

Two series of layered mixed oxides La4BaCu5-xMxO13+lambda(M = Mn, Co, x = 0 similar to 5) were prepared and characterized by means of XRD, XPS, O-2-TPD and chemical analysis. The results show that their structures are 5-layered ABO(3) perovskite, and the XPS and O-2-TPD investigation confirms that there exists synergistic effect between Cu ion and M when M ion is doped into the lattice of La4BaCu5O13+lambda,, and the synergistic effect between Mn and Cu is stronger than that of Cu-Co.

Synthesis, characterization and catalytic behavior of layered mixed oxides La4BaCu5-xMnxO12 in NO reduction by CO

A series of sample having the stoichiometry La4BaCu5-xMnxO12 (x = 0 similar to 5) were prepared, characterized by XRD, IR and H-2 - TPR and used as catalyst for NO + CO reaction. It was found that they have 5 - layered ABO(3) - type structure. The results of H-2 - TPR showed that the Cu ion was more easily reduced while a part of them was replaced by Mn ions. Their catalytic behavior to NO + CO reaction was investigate, La4BaCu2Mn3O12 showed the highest catalyst activity for the reaction than the others. The reaction mechanism is discussed:the activity of the catalysts could be attributed to the Cu ions, but it was improved when Mn ions took the place of some Cu ions.

Layered La-Ba-Cu mixed oxides with perovskite structure as catalyst for NO reduction by CO

The mixed oxides, including LaBa2Cu3O7, LaBaCu2O5, La4BaCu5O12 with perovskite structure, were prepared. The catalysts were characterized by means of chemical analysis, XRD, H-2-TPR. It was found that their structures were layered ABO(3) perovskite structure and they were the active catalysts for the NO reduction by CO. The existence of Cu3+ is an important factor to give the catalysts a high activity for the NO reduction by CO.

XPS Study on the Interaction between Layers and Pillars of Layered Double Hydroxides Pillared with Heteroplyanion (II)

Layered double hydroxides (LDHs) pillared with heteropolyanions have been measured using XPS, IR, XRD spertra, and the interaction between layers and pillars discussed, The mechanism of pillars has been further discussed by XPS spectra.

STUDIES ON THE SYNTHETIC, STRUCTURAL, ELECTRICAL, AND MAGNETIC-PROPERTIES OF THE NEW LAYERED OXIDES LN(2)MCO(2)O(7) (LN=SM, GD, M=SR, BA)

Three new oxides Ln(2)MCo(2)O(7) (Ln = Sm, Gd; M = Sr, Ba) have been synthesized in solid state reaction method. The powder X-ray diffraction spectra show that they are all isostructural with Sr3Ti2O7. The electrical resistivities in the temperature range 300-1100 K show that they are all semiconductors, and a transition to metals is observed at 1053, 1053, and 573 K for Sm2SrCo2O7, Gd2SrCo2O7, and Sm2BaCo2O7, respectively. The magnetic suspectivities of Gd2SrCo2O7 in the temperature range 300-673 K fit the Curie-Weiss law well. A plateau is observed in the curves of Sm(2)MCo(2)O(7) (M = Sr, Ba) which is attributed to the configuration state change of Co(III) from low spin to high spin. (C) 1995 Academic Press, Inc.

Synthesis and catalytic properties of layered double hydroxides pillared by heteropolyoxometalate

Layered double hydroxides (LDHs) pillared with heteropolyoxometalate have been synthesized via both restructuring of hydrotalcite-like compounds and direct anion exchange under microwave field. LDHs and their derivatives are both found to be efficient for alkylation of isobutane with butene with a higher butene conversion and selectivity towards C-8(0).

THE SYNTHESIS AND PHYSICAL-PROPERTIES OF THE NEW LAYERED LANTHANIDE ALKALINE-EARTH COBALT OXIDES [LN2MCO2O7 (LN=SM,GD M=SR,BA)]

Three new oxides Sm2SrCo2O7, Sm2BaCo2O7 and Gd2SrCo2O7 have been successfully synthesized by a solid state reaction method.The X - Ray diffraction spectra show that they are all isostructural with Sr8Ti 2O7, Ln2SrCo2O7(Ln=Sm, Gd) crystallized in the tetra