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Abstract: Three types of Eu3+-doped LaPO4 three-dimensional (3D) microstructures have been hydrothermally prepared by adjusting pH value and the molar ratio of La3+ and Eu3+ to phosphorus of Na5P3O10 (Ln/P) at 180°C. As the pH value was 0.15 and the molar ratio of Ln/P was in the range of 1/1 to 1/4, 5μm urchinlike spheres composed of long nanorods of hexagonal LaPO4:Eu were obtained. As the pH value was 1.00 and the molar ratio of Ln/P was 1/1, 3μm hollow spheres consisting of short nanorods of monoclinic LaPO4:Eu were prepared. Keeping the pH value at 1.0 and the molar ratio of Ln/P at 1/4, 6μm core–shell spheres of monoclinic LaPO4:Eu formed. Luminescent measurements were performed. Hollow spheres of monoclinic LaPO4:Eu had the strongest emission intensity. However, the emission intensity of monoclinic core/shell structure was even lower than that of hexagonal LaPO4:Eu urchinlike spheres. [ABSTRACT FROM AUTHOR]

Abstract: Fe3O4 hollow microsphere chains with lengths of 8–11 μm have been solvothermally synthesized in the mixed solution of glycerol and water with 1 M NaOH. The hollow microspheres have diameters in the range 0.7–1 μm, and the thickness of the shells is 150–300 nm. The shell of the hollow microspheres is constructed by octahedrons of 100–170 nm. However, when the concentration of NaOH is adjusted to 3 M, the octahedron chains with lengths of 30–50 μm can be obtained. The magnetic saturation values of hollow microsphere chains and octahedron chains are 88.1 and 102.4 emu/g at room temperature, respectively. [Copyright &y& Elsevier]

Abstract: The concentration of the Mn(NO3)2 solution has significant influence on the morphologies and the phases of the MnO2 products. A large number of - MnO2 nanowires were prepared via a simple pyrolysis under lower reaction concentration. The nanowires have lengths up to tens of micrometers and diameters in the range of 20–100 nm. The - MnO2 nanobundles and nanoflowers were prepared by increasing the concentration of Mn(NO3)2 solution. The superparamagnetism of - MnO2 nanowires and paramagnetism of - MnO2 nanoflowers indicate their potential applications in magnetic materials. [Copyright &y& Elsevier]

Abstract: Uniform bismuth selenide hollow nanospheres were synthesized on a large scale in a mixed solvent of ethylene glycol (EG) and oleic acid (OA). The diameter of the Bi2Se3 hollow nanospheres is about 600 nm and the thickness of the shell is about 40 nm. The shape evolution of Bi2Se3 nanostructures with different volume ratios of EG and OA was also observed: nanoflakes in EG solution, hollow nanospheres as of 2/3, and finally flower-like nanostructures in OA solution. [Copyright &y& Elsevier]

Abstract: Uniform ZnO urchin-like architectures were synthesized by hydrothermal decomposing Zn(OH)4 2− precursor with the assistance of dodecylamine (DDA) at 180°C for 12h. FESEM images display that the ZnO 3D urchin-like architectures are constructed of well-aligned ZnO nanorods with diameters of 50–80nm and lengths up to 2μm. Room temperature photoluminescence spectra of ZnO 3D architectures show an intensive ultraviolet emission at ∼385nm and weak green emission, which indicated their high structural and optical quality. [Copyright &y& Elsevier]

Abstract: Single crystalline nanobelts or nanoribbons and spherical or flower like hierarchical structures of α-MoO3 were obtained through homogeneous precipitation and subsequent hydrothermal treatment. It has been found that temperature, concentration of cationic surfactant cetyltrimethylammonium bromide (CTAB), and the addition order of reactants are the three critical factors for the assembly of nanobelts in the current process. [Copyright &y& Elsevier]

A new MnOOH precursor route has been developed to synthesize single-crystalline nanorods of tetragonal β-MnO2. Uniform γ-MnOOH nanorods were first prepared by reducing KMnO4 with KI under hydrothermal conditions at 120 °C. After calcination of the γ-MnOOH nanorods at 250 °C for 2 h in air, β-MnO2 nanorods retaining the morphologies of γ-MnOOH nanorods were obtained. The temperature, time and heating speed of calcination were found to be important for the morphologies of the β-MnO2 nanorods. [Copyright &y& Elsevier]

Nanocrystalline TiN, VN and CrN have been synthesized by a thermal nitridation reaction between the corresponding metal powder and NH4Cl at 600 °C in an autoclave. X-ray powders diffraction (XRD) indicated that these nanocystallites had a NaCl-type structure with lattice parameters: a=4.236 Å for TiN, 4.133 Å for VN, 4.145 Å for CrN. Transmission electron microscopy (TEM) showed these products consisted of cubic nanocrystals. X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) techniques revealed that all the products were almost pure nitrides. [Copyright &y& Elsevier]

Monodisperse Cu2O nanocubes are synthesized by reducing freshly prepared Cu(OH)2 with N2H4·H2O in water at room temperature. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations show that most of these nanocubes are uniform in size, with the average edge length of ∼500 nm. Selected area electron diffraction (SAED) investigation reveals that these nanocubes are single crystalline. Further, Cu2O nanoboxes are obtained by etching Cu2O nanocubes with acetic acid solution at room temperature. The nanoboxes retain the size and external morphology of the nanocubes. [Copyright &y& Elsevier]

Ag dendritic nanostructures were synthesized via a mild hydrothermal reaction using nickel nanotubes as reducing agent. The crystal morphologies changing from dendrite to compact crystals were investigated during the evolution of reaction system from non-equilibrium to quasi-equilibrium conditions. It was found that the strong shape anisotropy of Ni nanotube might influence the formation of dendritic patterns. The transition from silver dendrites to Ag compact crystals was investigated and the effect of surfactants is also discussed. [Copyright &y& Elsevier]

In this paper, we report the low-temperature synthesis of metal tungstate, MWO4 (M=Ca, Sr, Ba, Cd, Zn, Pb) nanocrystallites. By reaction between metal chloride and sodium tungstate in ethylene glycol at 180 °C for 10 h, well-crystallized tungstate particles were successfully obtained. Characterization by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) shows that the product powders consist of nanosize particles. Photoluminescence measurement reveals that the as-obtained CaWO4, CdWO4, and PbWO4 show excitonic peaks at about 430, 500 and 500 nm, respectively. The solvent and reaction conditions are important in the formation of the products. [Copyright &y& Elsevier]