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The synthesis, structural characterization, and photocatalytic properties of three new uranyl-organic coordination assemblies are described. The compounds are constructed from U-O polyhedra and naphthalenedicarboxylate linkers.

Four new rare-earth carboxylate materials are synthesized through a preheating and cooling-down crystallization technique and in the presence of N,N-dimethylformamide. This synthetic approach not only reduces the possibility of involvement of coordination water molecules in the compounds but also improves the solubility of aromatic carboxylic acids and therefore the formation of single crystals was suitable for structural analysis.

A silicoaluminophosphate with a chabazite (CHA) structure is chosen as a microspace provider to interact with metallic zinc for the chemical formation of mononuclear univalent zinc. This formation through chemical reaction with protons represents a new approach that opens vast vistas for the preparation of interesting paramagnetic compounds with univalent metal species.

ZnS-CHA (CHA = cyclohexylamine) nanocomposite, a unique inorganic-organic hybrid semiconductor, has been prepared from a mild solvothermal reaction system. This material contains 2 nm-sized ZnS nanoparticles, and is photoactive toward UV light (≤300 nm). Under UV-irradiation, the ZnS-CHA nanocomposite is transformed to crystalline zinc hydroxysulfate nanosheets. The driving force of the light-driven transformation reaction is the photogeneration of charges (electrons and holes) in the ZnS nanoparticles, and these photogenerated charges interact with the CHA molecules and the inorganic S2- species, leading to decomposition of the organic component and self-oxidation of the inorganic ZnS nanoparticles to form zinc hydroxysulfate. Through simple thermal treatment, the as-formed zinc hydroxysulfate nanosheets are converted to ultrathin ZnO nanosheets with a porous feature, which exhibit high sensitivity and fast response and recovery for ethanol detection when used as an electrical sensing material. [ABSTRACT FROM AUTHOR]

Three new uranyl-organic coordination polymers (UO2)8(NDC)12(4,4′-bipyH2)3(4,4′-bipyH)3 (1), (UO2)3O[Ag(2,2′-bipy)2]2(NDC)3 (2), and (UO2)2(NDC)2(2,2′-bipy)2 (3), where NDC = 1,4-naphthalenedicarboxylate and bipy = bipyridine, have been prepared in hydrothermal conditions. Both 1 and 2 possess a 2D structure while 3 is composed of 1D zigzag chains. In 1 there are mononuclear pentagonal-bipyramidal U-O polyhedra and 1D channels filled with 4,4′-bipy molecules, whereas in 2 there are mononuclear hexagonal-bipyramidal U-O polyhedra and tetranuclear pentagonal-bipyramidal U-O clusters which form 2D channels with occluded [Ag(2,2′-bipy)2]+ counterions. In 3 both the NDC and the bipy ligands coordinate to uranyl centers, leading to hexagonal-bipyramidal polyhedra which are connected to form 1D zigzag chains. Under UV or visible irradiation, 1 and 2 degrade rhodamine B with similar efficiency. The correlation between photocatalytic reaction rate and oxygen concentration for 1 and 2 has also been elucidated. Crystal data: 1, triclinic, space group P1, a = 11.037(2) Å, b = 15.126(3) Å, c = 15.660(3) Å, α = 62.05(3)°, β = 72.26(3)°, γ = 82.05(3)°, and Z = 2; 2, triclinic, space group P1, a = 14.161(3) Å, b = 15.122(3) Å, c = 18.212(4) Å, α = 85.73(3)°, β = 76.99(3)°, γ = 67.32(3)°, and Z = 2; 3, monoclinic, space group P21/n, a = 10.7976(18) Å, b = 31.501(6) Å, c = 11.590(2) Å, β = 97.609(4)°, and Z = 4. [ABSTRACT FROM AUTHOR]

Single-crystalline CuS hexagonal nanoplates have been prepared through a facile chemical vapor reaction (CVR) process in which sulfur vapor reacted with copper films in a vacuum chamber at about 450 °C for about 7 h. The parent copper films were obtained on a silicon wafer or glass slide through vacuum evaporation of metal copper. The effects of film thickness, reaction time, and temperature on CuS nanoplates growth were investigated, and the products were characterized by means of X-ray diffraction (XRD), element analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). The CuS hexagonal nanoplates are single crystals with an edge length of 0.2–1.8 µm and a thickness of 20–150 nm. Interestingly, the as-prepared CuS nanoplates are oriented in the direction perpendicular to the substrate surface with the c-axis parallel to the substrate surface. The possible formation mechanism of the CuS nanoplates has been elucidated. [ABSTRACT FROM AUTHOR]

Examines the effectiveness of the chemical preparation of compounds containing mononuclear univalent zinc (Zn) by choosing a silicoaluminophosphate with a chabazite (CHA) structure as the microspace provider to interact with metallic Zn. Structure of the molecular sieve designated as SAPO-CHA; Schematic representation of the formation of two Zn cations in one CHA cage of SAPO-CHA.