Hydrothermal Synthesis of Copper (II) Oxide Microparticle

CuO microparticle was syntheszied by hydrothermal method. The starting precursors were used as copper (II) nitrate trihydrate (Cu (NO3)2·3H2O), nitric acid (HNO3) and sodium hydroxide (NaOH). The final pH value of the mixed solution was used 2M NaOH to adjust the pH was 8 and treated at 100-200 oC for 4-6 h in a hydrothermal vessel. The black fine powder was obtained after dried at 100 oC for 5 h. The phase and structure of CuO microparticle were characterized by X-ray diffraction (XRD). A single phase monoclinic structure synthezied by hydrothermal method at 200 oC for 4 and 6 h was obtained without calcination steps. The morphology CuO microparticle was investigated by scanning electron microscopy (SEM). It was likely grain in shape and the particle size in range of 2.94-4.06 μm. The element composition of CuO microparticle was indicated by energy dispersive X-ray spectrometry (EDX). The chemical compositions showed the characteristic X-ray energy of copper (Kα = 0.98 keV) and oxygen (Kα = 0.53 keV), respectively. The functional group of CuO microparticle was indentified by Fourier transform spectrophotometry (FTIR). The wavenumber at 690, 514 and 437 cm-1 was corresponded to vibration of Cu-O stretching.

Crystal structure of a novel one-dimensional zigzag chain-like cobalt(II) coordination polymer constructed from 4,4′-bipyridine and 2-hydroxybenzoate ligands

A novel one-dimensional zigzag chain-like CoII coordination polymer constructed from 4,4′-bipyridine (4,4′-bpy) and 2-hydroxybenzoate (2-OHbenz) ligands, namely, catena-poly[[(4,4′-bipyridine-κN)(μ-2-hydroxybenzoato-κ2 O:O′)(2-hydroxybenzoato-κ2 O,O′)cobalt(II)]-μ-4,4′-bipyridine-κ2 N:N′-[aquahemi(μ-4,4′-bipyridine-κ2 N:N′)(2-hydroxybenzoato-κO(2-hydroxybenzoato-κ2 O:O′)cobalt(II)], [Co2(C7H5O3)4(C10H8N2)2.5(H2O)] n , has been synthesized by reacting cobalt(II) nitrate trihydrate, 4,4′-bpy and 2-hydroxybenzoic acid in a mixture of water and methanol at room temperature. There are two independent CoII centers, Co1 and Co2, in the asymmetric unit, revealing a distorted octahedral geometry with chromophore types of [CoN2O4] and [CoN2O3O′], respectively. The Co1 ions are doubly bridged by 2-OHbenz ligands with syn–anti coordination mode, generating a dinuclear unit. The bridging 4,4′-bpy ligands connect these dinuclear units and the mononuclear Co2 chromophores, providing a one-dimensional alternating zigzag chain-like structure. In the crystal, intermolecular hydrogen bonds, C—H...π and π–π stacking interactions are observed and these help to consolidate the packing. In addition, the physical properties of the title compound are reported.

Crystal structures of an imidazo[1,5-a]pyridinium-based ligand and its (C13H12N3)2[CdI4] hybrid salt

The monocation product of the oxidative condensation–cyclization between two molecules of pyridine-2-carbaldehyde and one molecule of CH3NH2·HCl in methanol, 2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridinium, was isolated in the presence of metal ions as bis[2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] tetraiodocadmate, (C13H12N3)2[CdI4], (I), and the mixed chloride/nitrate salt, bis[2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] 1.5-chloride 0.5-nitrate trihydrate, 2C13H12N3 +·1.5Cl−·0.5NO3 −·3H2O, (II). Hybrid salt (I) crystallizes in the space group P21/n with two [L]2[CdI4] molecules in the asymmetric unit related by pseudosymmetry. In the crystal of (I), layers of organic cations and of tetrahalometallate anions are stacked parallel to the ab plane. Antiparallel L + cations disposed in a herring-bone pattern form π-bonded chains through aromatic stacking. In the inorganic layer, adjacent tetrahedral CdI4 units have no connectivity but demonstrate close packing of iodide anions. In the crystal lattice of (II), the cations are arranged in stacks propagating along the a axis; the one-dimensional hydrogen-bonded polymer built of chloride ions and water molecules runs parallel to a column of stacked cations.

A temperature-responsive poly(vinyl alcohol) gel for controlling fluidity of an inorganic phase change material

A temperature-responsive PVA gel is achieved that reversibly holds fluid lithium nitrate trihydrate and releases it in response to temperature for easy gelling in-place and later removal from heat-exchange modules.

YCu(TeO3)2(NO3)(H2O)3: a novel layered tellurite

A new hydrated yttrium copper tellurite nitrate, yttrium(III) copper(II) bis[trioxidotellurate(IV)] nitrate trihydrate, has been synthesized hydrothermally in a Teflon-lined autoclave and structurally determined using synchrotron radiation. The new phase is the first example containing yttrium, copper and tellurium in one structure. Its crystal structure is unique, with relatively strongly bound layers extending parallel to (020), defined by YO8, CuO4and TeO3polyhedra, while the NO3−anions and one third of the water molecules lie between those layers. The structural unit consists of [Cu2(TeO3)4]4−loop-branched chains of {Cu...Te...Cu...Te} squares running parallel to [001], which are linked further into layers only through Y(O,H2O)8polyhedra. Weak `secondary' Te bonds and O—H...O hydrogen-bonding interactions, involving water molecules and layer O atoms, link the layers and interlayer species. IR spectroscopic data are also presented.