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Abstract: Orthorhombic single-crystal CeCO3OH flower-like nanostructures have been successfully synthesized on a large scale by the hydrothermal method at 120°C using Ce(NO3)3·6H2O as the cerium source, aqueous urea as both an alkaline and carbon source and polyvinyl alcohol as surfactant. Polycrystalline CeO2 nanostructures have been obtained by thermal decomposition–oxidation of single-crystalline CeCO3OH flower-like nanostructures at 500°C in flowing air. CeCO3OH flower-like nanostructures and CeO2 nanostructures were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), room temperature UV/vis absorption spectrum, differential scanning calorimetric analysis (DSC), and thermogravimetric analysis (TG). The high absorption in the UV region for CeO2 nanostructures indicated that this material was suitable as UV-blocking material. [Copyright &y& Elsevier]

Abstract: Octahedral Cu2O particles and Cu2O nanowires were synthesized by a simple solution-phase route using N2H4·H2O as reducing agent at room temperature. Amorphous carbon nanofibers were synthesized using octahedral Cu2O particles and an acetylene gas source at atmospheric pressure. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and thermogravimetric (TG) analysis. SEM and TEM images indicated that most of the obtained octahedral Cu2O particles had an edge length of 400–700nm. The obtained nanowires had uniform diameters of about 15nm, and the length of the nanowires ranged from 5 to 10μm. The XRD result revealed the amorphous feature of the nanofibers. IR spectrum revealed that the nanofibers consist of –CH, –CH2, –C and –CH3 groups. The concentrations of N2H4·H2O and NaOH played important roles in controlling the geometric shape of the Cu2O. [Copyright &y& Elsevier]

Abstract: Orthorhombic single-crystalline cerium carbonate hydroxide (CeCO3OH) with one-dimensional (1D) microstructures has been successfully synthesized by a facile sonochemical reaction between cerous nitrate and urea. These 1D microstructures were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM). The as-synthesized CeCO3OH has uniform lengths and good dispersion. Synthetic parameters, such as the concentration of reagents, were found to have close relationship with the morphologies and sizes of the final products. The ultrasound-induced oriented attachment growth mechanism has been proposed for the possible formation mechanism of sample. Room-temperature photoluminescence of CeCO3OH samples with different morphologies has also been investigated. [Copyright &y& Elsevier]

CeO2 hollow microspheres have been synthesized by hydrothermal decomposition reaction of Ce(NO3)3 on the surfaces of silica microspheres. The shell thickness of CeO2 hollow microspheres can be controlled from 20 to 50nm by adjusting the concentration of Ce(NO3)3 in the reaction solution. The high UV absorption of CeO2 hollow microspheres indicates that this material is suitable as a UV-blocking material. [Copyright &y& Elsevier]

Abstract: The controllable synthesis of hexagonal flower-like Zn-doped CdSe (Cd1−x Zn x Se, x =0.1) microstructures from the solid air-stable precursor has been achieved by two facile steps: first, precursors were prepared directly through precipitation reactions of stoichiometric cadmium acetate, zinc acetate and sodium selenite in distilled water under ambient condition; second, pure hexagonal phase flower-like Cd0.9Zn0.1Se were produced via solvothermal treatment of the precursor compound in ethylenediamine (en) at 180°C. The products were characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrum (EDS) and UV–vis absorption spectroscopy. It was observed that the optical band gap energies of the as-synthesized flower-like Cd0.9Zn0.1Se microstructures shift toward shorter wavelengths compared with CdSe. [Copyright &y& Elsevier]

Abstract: The controllable synthesis of hexagonal pine-like Zn-doped CdSe (Cd1−x Zn x Se, x =0.1–0.3) nanotrees from the self-prepared mixed-metal precursors has been achieved by two facile steps: first, mixed-metal precursors (x =0.1–0.3) were prepared directly through precipitation reactions of stoichiometric cadmium acetate, zinc acetate and sodium selenite in distilled water under ambient condition; second, pure hexagonal phase pine-like Cd1−x Zn x Se (x =0.1–0.3) nanotrees with different ratios were produced via solvothermal treatment of the precursor compounds in hydrazine hydrate at 180°C for 12h. The products were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrum (EDS) and UV–vis absorption spectroscopy. It was observed that the optical band gap energies of the as-synthesized Cd1−x Zn x Se (x =0.1–0.3) nanotrees shift systematically toward shorter wavelengths with an increase of the Zn content. [Copyright &y& Elsevier]