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Abstract: Graphene-like structure of V2O3 had been synthesized by a top-down precursor-pyrolyzation strategy. The first-order transformation of V2O3 disappeared with the increasing of temperature. It represents a positive temperature coefficient semiconductor behavior. It is a noteworthy and promising candidate for ultrathin energy-storage devices. The discharge capacity of V2O3 nanosheets is maintained at 300mAh/g after 75 cycles at the current density of 200mA/g, which exhibits excellent discharge capacity and superior cycling stability. Flower-like precursors composed of nanosheets were also successfully synthesized by adjusting temperature and time. V2O3 has perfectly inherited the morphology of its precursors. The new method demonstrated here provides a new way in the preparation of other ultrathin nanosheets materials. [Copyright &y& Elsevier]

Abstract: A series of carbides (TiC, V2C, Mo2C) were synthesized by the corresponding metal oxides (TiO2, V2O5, MoO3), CaC2 and magnesium as starting materials in a stainless steel autoclave at 600°C. Through similar processes, transition metal nitrides (TiN, VN and CrN) could also be produced by employing the corresponding metal oxides (TiO2, V2O5, Cr2O3), NaNH2, and magnesium as starting materials at 550°C. The FE-SEM image showed that the TiC sample was mainly consisted of flower-like microstructures. TEM image showed the other carbides (V2C, Mo2C) and the obtained nitride (TiN, VN, CrN) were consisted of nanoparticles. The possible synthesis mechanism of TiC had been described. [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: CdSe micro/nanocrystals with multiform morphologies, including multi-foots rods, flower-like structures and hollow spheres, have been successfully synthesized by a facile solvothermal method in ethylene glycol (EG). These morphologies could be achieved simply by varying the cadmium source. In addition, different crystal phases of the as-obtained CdSe micro/nanocrystals have also been successfully controlled. Furthermore, the possible growth mechanism for different morphologies and crystal phases of CdSe micro/nanocrystals were also discussed. [Copyright &y& Elsevier]

Abstract: Porous soft magnetic material is a member of soft magnetic material family having large surface area. This kind of material has vast potential in the surface-related applications. In this paper, a kind of maghemite (γ-Fe2O3) with large surface area, 82.7m2/g, specifically, was obtained by the solvothermal method and subsequent calcining process. As shown in the test results, the maghemite microsphere has no magnetic memory in the magnetic field since the residual magnetization is 0.7emu/g. In the waste water treatment process, Rhodamine B, a model organic pollutant in the water, was removed through the adsorption and desorption cycles by the maghemite microspheres. The maghemite microspheres in the water can be recycled easily by a magnetic separation procedure and regenerated in ethanol at room temperature. [Copyright &y& Elsevier]

Abstract: Ca9Co12O28 nanoparticles with size of about 25nm were prepared by Pechini process at 850°C for 4h. The as-obtained nanoparticles demonstrated initial charge/discharge capacities of 908 and 816mAh/g and a stable discharge capacity of 210mAh/g after 50 cycles. Different morphologies of Ca9Co12O28 as multilayer structure and micro-plates were also obtained by solid-state reaction and coprecipitation-precursor technique at 850°C for 20h. When they were studied in the charge/discharge experiments of lithium ion batteries, the initial discharge capacities reached values of 762 and 790mAh/g, together with stable discharge capacities of 141 and 151mAh/g after 50 cycles, respectively, which were both lower than those of nanoparticles. [Copyright &y& Elsevier]

Abstract: Rhombohedra microcrystallites of magnesium carbonate (MgCO3) have been hydrothermally synthesized by urea and magnesium sources (Mg, MgCl2, Mg(OH)2, MgSO4, and MgO) at 160°C. The experimental parameters such as reaction temperature, time, and reactants were researched to investigate the reaction mechanism. The product synthesized by Mg powder was about 10μm, and the diameters of the products synthesized by Mg(OH)2 and MgSO4 were about 1–2μm. The product could transfer from the mixture of MgCO3, Mg(OH)2, Mg5(CO3)4(OH)2·4H2O to pure MgCO3 by increasing reaction time or raising reaction temperature, which indicates that Mg5(CO3)4(OH)2·4H2O was just the intermediate product, and MgCO3 was the final product. [Copyright &y& Elsevier]

Abstract: Single-crystalline 3C–SiC nanowires have been synthesized in large scale through a one-step autoclave route by the reaction of SiCl4, (C5H5)2Fe and metallic Na at 500 °C. Electron microscopy investigations show that the nanowires have typical diameters of 15–50 nm, lengths up to several tens of micrometers and grow along the [111] direction. The possible growth mechanism of the nanowires is discussed. [Copyright &y& Elsevier]

Nanocrystalline ZrB2 has been prepared by the reaction of ZrCl4 with NaBH4 in the temperature range of 500–700 °C. The microstructure of the powders consists of uniform particles about 20 nm in size. The UV–vis absorption spectra and thermal oxidation behavior of the products are studied. [Copyright &y& Elsevier]