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Abstract: Hexagonal boron nitride (h-BN) particles including hollow spheres (with a proportion of ~30–40%) and nanotubes (10%) have been synthesized by using sodium fluoroborate and sodium azide at 450°C for 20h. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) studies show that the as-obtained BN hollow particles are crystalline. The total specific surface area of the product calculated from Brunauer–Emmentt–Teller (BET) absorption measurement is 89.79m2/g, indicating that it may be utilized as a promising candidate for hydrogen storage container or catalyst. Thermal gravimetric analysis (TGA) result reveals its excellent thermal stability below 800°C. Its possible growth mechanism and the effects of reaction parameters were also briefly discussed. [Copyright &y& Elsevier]

Abstract: Fe3O4 microoctahedrons have been synthesized through a hydrothermal reduction approach using K3[Fe(CN)6] complex as a single precursor. The X-ray diffraction (XRD) pattern indicates that the as-synthesized Fe3O4 microoctahedrons are well crystallized. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images show that the final product consists of larger numbers of microoctahedrons with the size ranging from 1.2 to 4μm. Selected-area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM) images prove that the Fe3O4 microoctahedrons are single crystals. The effect of reductant, NaOH concentration, temperature, reaction time on the morphologies of the final product has been investigated, and a possible solid–solution–solid growth mechanism is suggested to explain the formation of Fe3O4 microoctahedrons. The magnetic properties of the structure show relatively high saturation magnetization (112.7emu/g) and coercivity (102.8Oe) detected by a vibrating sample magnetometer. [Copyright &y& Elsevier]

Abstract: Copper (Cu) plate-like and shrub-like micro-scale crystallites were synthesized by a facile hydrothermal method using formaldehyde (HCHO) as the reducing agent in NaOH aqueous solution at 180°C. The X-ray diffraction patterns indicate that the as-synthesized Cu crystallites were well crystallized and with pure phase. FESEM and TEM images reveal that the final plate-like products consist of lager numbers of triangular and hexagonal plates with the edge length ranging from 0.5 to 4μm and with the thickness ranging from 250 to 350nm, and the shrub-like products are composed of some dendrites. SAED and HRTEM images prove that the Cu plates are singe crystals and covered by {111} facets. The effect of capping agent, NaOH concentration, reaction time and temperature on the morphologies of the final products has been investigated, and their possible formation mechanisms were also discussed. [Copyright &y& Elsevier]

CaV6O16·3H2O nanoribbons have been prepared by the hydrothermal method in the presence of sodium dodecyl sulfate (SDS) at 160°C for 10 h. X-ray diffraction pattern indicates that the sample is monoclinic phase of CaV6O16·3H2O with the lattice contents a=12.18 A˚, b=3.598 A˚, c=18.39 A˚, β=118.03°. Field emission scanning electron microscopy shows that the nanoribbons have widths in the range of 150–500 nm, thicknesses of 30–60 nm and lengths of ∼500 mm X-ray photoelectron spectrum measurements further confirm the formation of the CaV6O16·3H2O phase. The formation of CaV6O16·3H2O nanoribbons is a self-assembling process, in which surfactant SDS plays the role of soft template. [Copyright &y& Elsevier]

Coral-shaped nanocrystallites of Cu3BiS3 and AgBiS2 have been synthesized at 195°C from single-source precursors by a rapid polyol process. X-ray powder diffraction, X-ray photoelectron spectra and transmission electron microscope were used to characterize the products, which reveal that the products are phase-pure coral-shaped nanostructures. The formation mechanism is also discussed. [Copyright &y& Elsevier]

ZnSe spheres with diameters of about 1 μm have been prepared via a rapid polyol process by refluxing the raw materials in ethylene glycol at 195°C for only 1 h; the X-ray diffraction pattern indicated that the as-prepared sample is cubic ZnSe phase. The products were also characterized by X-ray photoelectron spectroscopy, FT-IR, Raman and field-emission scanning electron microscope procedures. And studies found that the reaction time had great influence on the morphology of the products. [Copyright &y& Elsevier]

A convenient hydrothermal decomposition process has been developed to prepare cupric oxide shuttle-like nanocrystals using CuCl2·H2O and NaOH as the starting materials. The product was characterized by X-ray diffraction, scanning electron microscopy, Raman spectra and X-ray photoelectron spectroscopy. The results showed that the as-prepared CuO shuttle-like crystals have regular shape, uniform size distribution and with high yield. [Copyright &y& Elsevier]

BaWO4 crystals with different morphology, such as olive-like, flake-like, and whisker-like structure have been successfully prepared through a hydrothermal process in the presence of different surfactants—C17H33COOK, C19H39COOK, and C25H51COOK, respectively. X-ray powder diffraction (XRD) shows that the crystals have been well crystallized. The observation results of scanning electron microscopy (SEM) on the obtained samples have revealed that the selection of surfactants and the concentration of the starting materials can highly affect the morphology and size of BaWO4 crystals. [Copyright &y& Elsevier]

The direct polyol method is used to prepare silver bismuth sulfide AgBiS2 nanorods. X-ray powder diffraction patterns indicate that AgBiS2 is cubic with a cell constant a=5.651 A˚. Transmission electron microscopy images reveal that the product consists of uniform rod-like crystals with diameters of about 40 nm and lengths up to 10 μm. A possible formation mechanism of silver bismuth sulfide is proposed. [Copyright &y& Elsevier]