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Abstract: Hollow carbon octahedra with an average size of 300nm and a shell thickness of 2.5nm were prepared by a reaction starting from ferrocene and Mg(CH3COO)2·4H2O at 700°C for 10h. They became compressed and turned into deflated balloon-like octahedra when the reaction time was increased to 16h. It was proposed that the gas pressure generated during the reaction process induced the transformation from broken carbon hollow octahedra into deflated balloon-like compressed octahedra. X-ray powder diffraction and Raman spectroscopy indicate that the as-obtained carbon products possess a graphitic structure and high-resolution transmission electron microscopy images indicate that they have low crystallinity. Their application as an electrode shows reversible capacity of 353mAhg−1 after 100 cycles in the charge/discharge experiments of secondary lithium ion batteries. [Copyright &y& Elsevier]

Abstract: Honeycomb-like graphitic macroporous carbon (HGMC) was synthesized by means of pyrolysis of NH4HCO3 using Mg powder as reductant in an autoclave at 550°C. The characterization of structure and morphology was carried out by X-ray diffraction (XRD), Raman spectrum, field-emission scanning electron microscopy (FESEM), and (High-resolution) transmission electron microscope [(HR)TEM]. The results of nitrogen adsorption–desorption indicate that the products are macropore materials with the pore size of 1–3μm, and the Brunauer–Emett–Teller (BET) surface area was 14m2/g. As a typical morphology, the possible growth process of HGMC was also investigated and discussed. The experimental results show that the in situ formed MgO microparticles play a template role during the HGMC formation. [Copyright &y& Elsevier]

Abstract: Sb2O3 nanorods were successfully prepared via a mild hydrothermal route based on the reactions between SbCl3 and NH3·H2O in aqueous solution at 120–180°C for 12h. The as-prepared Sb2O3 nanorods were characterized by X-ray diffraction (XRD), transmission electronic microscopy (TEM), and X-ray photoelctron spectroscopy (XPS). Results showed that NH3·H2O played a significant role in the formation of Sb2O3 nanorods. The presence of NH3·H2O could greatly favor the reaction progress toward the right-hand side and led to the orientation growth of Sb2O3 nanorods. A possible mechanism for the formation of Sb2O3 nanocrystallites was discussed. [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]

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]

The novel polygonal flake like Ag8SnS6 crystal, Cu2FeSnS4 flaky, and well-dispersed Cu2CoSnS4 nanoparticles were successfully prepared via a convenient hydrothermal reaction route at relatively low temperature, which was avoiding the use of high temperature treatments or toxic organic solvents. The products were characterized by means of X-ray powder diffraction (XRD), transmission electronic microscopy (TEM), X-ray photoelectronic spectra (XPS) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). It was found that the reaction temperature played a key role for the formation of the target products. [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]

Abstract: Nanocrystalline gallium nitride was synthesized by a solid-state reaction of metallic magnesium powder, gallium sesquioxide and sodium amide in a stainless steel autoclave at a relatively low temperature (400–550°C). The structures and morphologies of the obtained products were derived from X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). XRD patterns indicated that the products were hexagonal GaN (JCPDS card no. 76-0703). The influence of reaction temperature on size of the products was studied by XRD and TEM. Furthermore, the thermal stability and oxidation resistance of the nanocrystalline GaN were also investigated. It had good thermal stability and oxidation resistance below 800°C in air. [Copyright &y& Elsevier]