A novel cadmium(Ⅱ) coordination polymer {[Cd(1,5-nds)(Him)2(H2O)]·2H2O}n(1,5-nds = naphthalene-1,5-disulfonate and Him = imidazole) was synthesized based on the reaction of cadmium oxide and 1,5-naphthalenedisulfonic acid firstly,and then mixed with imidazole in methanol medium.Its structure was characterized by elemental analysis,IR and TGA,respectively.The crystal structure was determined by single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P,with a = 8.5420(10),b = 10.2570(10),c = 13.361(2) ,α = 100.704(2),β = 100.195(2),γ = 108.873(3)o,C16H20Cd N4O9S2,Mr = 588.91,V = 1.0524(2) nm3,Dc = 1.858 g/cm3,Z = 2,F(000) = 592,μ = 1.294 mm-1,R = 0.0397 and wR = 0.1007 for 3180 observed reflections(Ⅰ > 2σ(Ⅰ)).Structural analysis shows that the cadmiun atom is coordinated with four oxygen atoms from three 1,5-nds and one water molecule together with two nitrogen atoms from two imidazoles,giving a distorted octahedral coordination geometry.The molecules are linked to form a two-dimensional coordination polymer based on bridging ligands of naphthalene-1,5-disulfonate anions,the sheets of which are then interacted via hydrogen bonds,leading to a three-dimensional network structure.
A facile approach to preparing well-dispersed nanocrystals of BaCeO3 was developed by a combination of solvothermal and an- nealing processes. The precursor consisted of amorphous BaCO3 and CeO2, and the conversion of the precursor to crystalline BaCeO3 nanocrystals occurred upon heat treatment at a relatively low temperature. The as-processed BaCeO3 had an orthorhombic structure and the average size of such crystals was approximately 80 nm. The obtained products were characterized by Fourier Transform Infrared (FT-IR), X-Ray Diffraction (XRD), Laser Raman Spectroscopy (LRS), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectrome- try (EDS), and Transmission Electron Microscopy (TEM). This preparation process could also be used to synthesize doped barium cerate complex oxides BaCe0.95M0.05O3-δ (M=Y, Nd, Gd, and Sm).
A facile solution-phase route for the synthesis of shape-controlled ZnO nanocrystals in a polyol/water mixture system was developed. The obtained nanocrystals were characterized by X-ray diffraction, transmission electron microscopy and UV-visible absorption spectroscopy. The results indicate that modulating the adding ways of water has a significant effect on the shape of the obtained nanocrystals. The addition of small quantity of water can increase the growth rate of crystals and leads to the formation of different shapes. The resulting shapes of the novel structures are diverse, including spheres, cones, and teardrops, all of which are obtained without any additional surfactants. These studies concerning the shape evolution of nanocrystals should be valuable for further design and for greater understanding of advanced nanoscale building-block architectures.
