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Abstract: In this paper, hollow spherical Cu3P nanopowders were synthesized by using copper sulfate pentahydrate (CuSO4⋅5H2O) and yellow phosphorus in a mixed solvent of glycol, ethanol and water at 140–180 ∘C for 12 h. X-ray powder diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), electron diffraction pattern (ED) and transmission electronic microscopy (TEM) studies show that the as-synthesized nanocrystal is pure hexagonal phase Cu3P with a hollow spherical morphology. Based on the TEM observations, a possible aggregation growth mechanism was proposed for the formation of Cu3P hollow structures. Meanwhile, the effects of some key factors such as solvents, reaction temperature and reaction time on the final formation of the Cu3P hollow structure were also discussed. [Copyright &y& Elsevier]

Abstract: Nanocrystalline niobium nitride was synthesized via benzene-thermal reaction of NbCl5 and NaN3 in an autoclave at 380°C. X-ray powder diffraction pattern indicated that the product was cubic NbN, and the cell constant was a = 4.419Å. Transmission electron microscopy image showed that the sample consisted of particles with the diameters of 10–20nm. Benzene solvent played an important role in the formation of nanocrystalline NbN. [Copyright &y& Elsevier]

In this work, various novel NiO hierarchical nanostructures, including mesoporous nanotubes by nanoparticles self-assembly, nanowire bundles, dandelions, hollow spheres by rods self–assembly, have been fabricated by a simple hydrothermal process and subsequent thermal decomposition at atmosphere. A detailed study of the effect of experimental parameters on the morphology is also presented. Results and analyses demonstrated that oxalic-acid/NaOH molar ratio has an immense function in the subtle morphology control of NiO products. Electrochemical characterization demonstrated that the mesoporous NiO nanotubes were capable of delivering a specific capacitance (SC) of 405 F g−1at the current density of 0.5 A g−1and offered good capacitance retention of ca.91% after 1500 continuous charge-discharge cycles. This soundly indicates that as electrode material, the as-prepared NiO mesoporous nanostructures could meet key requirements in terms of large power density, outstanding rate capability and excellent electrochemical stability. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline InP hollow nanospheres with an average size of 520nm and shell thickness of about 110nm were obtained by acid treatment of In/InP core–shell nanospheres which were solvothermally synthesized in ethanolamine–water binary solution at 180°C. The sizes of InP hollow nanospheres increased with the increasing reactants quantities. Meanwhile the shell thicknesses of InP hollow nanospheres could be controlled by varying the quantity of yellow phosphorus. The process of In/InP core–shell nanospheres transforming into InP hollow nanospheres was also investigated. The InP products prepared in our experiments can emit blue light, which is different from previous reports and increases the potential application of InP nanomaterial. [Copyright &y& Elsevier]

Nanocrystalline chromium disilicide was synthesized by co-reducing anhydrous chromium trichloride and sodium fluorosilicate with metallic potassium at 650 °C in an autoclave. X-ray powder diffraction pattern indicated that the product was hexagonal CrSi2. Transmission electron microscope images showed that the sample consisted of particles with the diameters of 20–50 nm and an average diameter of about 35 nm. TGA and DTA indicated that the oxidation of CrSi2 began to proceed at 700 °C in air, and only about 8.6 wt.% of the sample was oxidized in the surfaces of the particles below 1000 °C. It had high thermal oxidation stability due to the formed protective layer. [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]

Nano-crystalline vanadium disilicide was successfully synthesized using vanadium tetrachloride and silicon as starting materials via reduction–silication route at 650 °C in the molten salt solution of magnesium chloride and sodium chloride in an autoclave. X-ray powder diffraction patterns indicated that the product was hexagonal VSi2 (a=4.572 A˚, c=6.372 A˚). Transmission electron microscopy images showed that the particle size of the product was in the range of 40–60 nm in diameter. There was a strong absorption peak at 271 nm in the UV-Vis absorption spectra. The oxidation of nano-crystalline VSi2 began to proceed at the temperature of 400 °C in air. But the product had high thermal oxidation stability below 1000 °C. It can be used as an antioxidation coating material. [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]

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]

A simple and convenient polyol-mediated route has been developed to produce nanocrystalline Ag3SbS3 and Cu3SbS3 from AgNO3 and Cu(NO3)2 and SbCl3 with thiourea at 197 °C. The products were characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. Analysis shows that glycol agitated state and injection rate have a great effect on the purity of the final products. [Copyright &y& Elsevier]