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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]

Titanium diboride (TiB2) has been synthesized via a benzene-thermal reaction of metallic sodium with amorphous boron powder and titanium tetrachloride at 400 °C in an autoclave; the temperature was much lower than that of traditional methods. The X-ray diffraction (XRD) pattern can be indexed with the hexagonal cell of TiB2 and the lattice constants a=3.027 and c=3.228 A˚. X-ray photoelectron spectroscopy (XPS) results show the mole ratio of Ti:B as 1:1.766. Transmission electron microscope (TEM) images indicate that the average particle size is in the range of 15–40 nm in diameter. [Copyright &y& Elsevier]

X-ray powder diffraction and high-resolution transmission electron microscopy (HRTEM) have found coexistence of three structures of GaN: wurtzite, zinc blende, and rocksalt in the samples prepared through benzene thermal process at 280–300 °C under pressure about 5 MPa. Previously, GaN with rocksalt structure only appeared at high pressure more than 37 GPa. HRTEM showed that there was a transitional region between the two cubic phases of GaN with zinc blende and rocksalt. X-ray photoelectron spectra analysis of the sample gave the average composition of Ga0.95N. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A method for detecting large-size diamonds with low content in a complex mixture was described. Phase identification via conventional X-ray diffraction method is unsuitable because of the large-size and low-content characteristics of the diamonds. Thus, we proposed a convenient approach (i.e., rocking scan) for assessing the presence of low-content diamonds in a complex mixture. A thorough rocking scan of the (111), (220), and (311) planes revealed the presence of low-content diamonds prepared by reducing dense carbon dioxide with alkali metals. This procedure can be successfully applied to several standard mixture samples prepared by mixing α-SiO 2 , α-Al 2 O 3 , graphite, and pure diamond powders, which are commercially available. We estimated that the detection limit was at or below the 0.1 wt% level by using the proposed method under the current condition. This method is straightforward, routinized, and may be specifically developed to satisfy the requirements of public and private institutions for a rapid identification of other mixture phases, of which the large-size and low-content characteristics do not allow an instant phase identification by conventional X-ray diffraction methods. [ABSTRACT FROM AUTHOR]

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]

Presents information on a study which examined the phase decomposition in a high quality bismuth compound single crystal annealed in air, using x-ray diffraction and scanning electron microscopy. Methods; Results; Discussion.

In this work, we have developed a simple and facile method to synchronously synthesize hollow FeSe2/C nanospheres using the Kirkendall effect. When evaluated as an anode for SIBs, the hollow FeSe2/C nanospheres exhibit a high discharge capacity retention of 474.1 mA h g−1 at 0.05 A g−1 (based on the calculation of FeSe2), which is very close to the theoretical capacity of FeSe2 (∼500 mA h g−1). Meanwhile, hollow FeSe2/C also has a superior rate capability of 364.5 and 316.5 mA h g−1 even at 2.0 and 5.0 A g−1, respectively. The high performance of the hollow FeSe2/C nanospheres can be ascribed to the unique carbon coated hollow nanostructure. [ABSTRACT FROM AUTHOR]

N-doped Si nanoparticles were prepared synchronously by nitridation of Mg2Si. The existence of nitrogen doping can be demonstrated by the XPS spectrum and EELS energy-filtered images. When the N-doped Si nanoparticles were used as an anode for Li-ion batteries, a high reversible capacity of 2595 mA h g−1 at 0.36 A g−1 after 40 cycles, and 805 mA h g−1 at 3.6 A g−1 after 800 cycles could be obtained. [ABSTRACT FROM AUTHOR]

Urchin-like Sn-ZnO-C composite have been successfully prepared by thermal annealing of ZnSn(OH) precursor in acetylene/argon gas (1/9; v/v). The phase of the urchin-like Sn-ZnO-C has been characterized by X-ray diffraction (XRD) and Raman spectrum. The images of scanning electron microscopy (SEM) and transmission electron microscope (TEM) demonstrate that the Sn-ZnO-C composite with an average of 3 μm in diameter is composed of many core-shell nanowires and carbon nanotubes emanated from the center. The thermal annealing temperature and time have crucial effects on the formation of urchin-like structure and carbon content of the Sn-ZnO-C composites. As an anode for lithium-ion batteries, the urchin-like Sn-ZnO-C composite delivers a discharge capacity of 1,034.5 mAh/g in initial cycle and 571.9 mAh/g reversible discharge capacity after 25 cycles at a current density of 50 mA/g. The superior energy storage properties highlight the urchin-like Sn-ZnO-C composite as a potential alternative anode material in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: The micro-/nanoscale Cu/Li4Ti5O12 composites were prepared by a solvothermal method. The X-ray diffraction (XRD) and the transmission electron microscopy (TEM) images reveal that the addition of Cu has no effect on the crystal structure of spinel Li4Ti5O12 and the Cu nanoparticles dispersed in the matrix of Li4Ti5O12. As an anode material for rechargeable lithium-ion batteries, the Cu/Li4Ti5O12 composite with Cu content of 15wt.% exhibited the better rate and cyclic performance than those samples of Cu/Li4Ti5O12 with Cu content of 0wt.%, 3.75wt.%, 7.5wt.%, 22.5wt.%. The initial discharge capacity of Cu/Li4Ti5O12 composites with Cu content of 15wt. % at 20C rate is 122.9 mAh/g and remains as high as 107 mAh/g after 1000 cycles (87% retention). Meanwhile, we did some comparable experiments, the results show that the Cu/Li4Ti5O12 (15wt.%) composite also exhibits a good electrochemical performance even without the acetylene black. The enhanced performance for the composites (Cu 15wt. %) is ascribed to the improved electronic conduction and the reduced polarization resulting from the appropriate Cu modification together with micro- and nanosized structure when used as an anode electrode material. [Copyright &y& Elsevier]

Abstract: MFe2O4 (M = Zn, Co, Ni) nanorods are synthesized by a template-engaged reaction, with β-FeOOH nanorods as precursors which are prepared by a hydrothermal method. The final products are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). The electrochemical properties of the MFe2O4 (M = Zn, Co, Ni) nanorods are tested as the anode materials for lithium ion batteries. The reversible capacities of 800, 625 and 520 mAh g−1 are obtained for CoFe2O4, ZnFe2O4 and NiFe2O4, respectively, at the high current density of 1000 mA g−1 even after 300 cycles. The superior lithium-storage performances of MFe2O4 (M = Zn, Co, Ni) nanorods can be attributed to the one-dimensional (1D) nanostructure, which can shorten the diffusion paths of lithium ions and relax the strain generated during electrochemical cycling. These results indicate that this method is an effective, simple and general way to prepare good electrochemical properties of 1D spinel Fe-based binary transition metal oxides. In addition, the impact of different reaction temperatures on the electrochemical properties of MFe2O4 nanorods is also investigated. [Copyright &y& Elsevier]

Abstract: α-Fe2O3 nanotubes and nanorods are obtained via a hydrothermal method without further annealing. Both of them are characterized by X-ray powder diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. The lithium-storage performances of the nanostructures are measured and compared in terms of reversible capacity, cycling stability, and rate capability. The electrode based on the nanotubes delivers the reversible capacities of 1200 mAh g−1 at 100 mA g−1, 1000 mAh g−1 at 500 mA g−1, and 810 mAh g−1 at 1000 mA g−1 after 60 cycles, much higher than those based on the nanorods. The better performances of the nanotubes could be assigned to their tubular morphology that tolerates the huge volume change during the discharge/charge processes and possesses the large surface area to increase the contact between the electrode and the electrolyte. These insights will be of benefits in the design of other anode materials for lithium ion batteries. [Copyright &y& Elsevier]

Abstract: General and simple methods for the syntheses of borides, carbides and nitrides are highly desirable, since those materials have unique physical properties and promising applications. Here, a series of boride (TiB2, ZrB2, NbB2, CeB6, PrB6, SmB6, EuB6, LaB6), carbide (SiC, TiC, NbC, WC) and nitride (TiN, BN, AlN, MgSiN2, VN) micro/nanocrystals were prepared from related oxides and amorphous boron/active carbon/NaN3 with the assistance of metallic Na and elemental S. In-situ temperature monitoring showed that the reaction temperature could increase quickly to ∼850°C, once the autoclave was heated to 100°C. Such a rapid temperature increase was attributed to the intense exothermic reaction between Na and S, which assisted the formation of borides, carbides and nitrides. The as-obtained products were characterized by XRD, SEM, TEM, and HRTEM techniques. Results in this report will greatly benefit the future extension of this approach to other compounds. [Copyright &y& Elsevier]

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]

Sphere-like Mo2C nanoparticles have been synthesized through the reaction of sodium molybdate, anhydrous ethanol and sodium azide at 450 °C for 10 h in a sealed stainless steel autoclave. X-ray powder diffraction results indicated that the final product was Mo2C. Transmission electron microscopy (TEM) and scanning elctron microscopy (SEM) were employed to characterize the as-prepared sample. The sample was mostly composed of sphere-like particles, which has a superconducting transition temperature of 9.5 K, and its calculated surface area is 30.859 m2/g. The experimental parameters such as reaction temperature and reactants were studied to investigate the reaction mechanism. It was found that sodium azide and reaction temperature played key roles in the formation of sphere-like Mo2C nanoparticles. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

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]

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: Cubic phase silicon carbide (3C-SiC) nanowires (labeled as “Sample 1”) with diameters ranging from 10nm to 80nm and lengths up to several micrometers were obtained by using CHI3, Si powder, and metallic Na as reactants at 230°C. In addition, SiC polyhedra (labeled as “Sample 2”) with smooth surfaces and diameters of 2–5μm were obtained by using the different amounts of the same reactants at 500°C. The room-temperature photoluminescence (PL) spectra of Sample 1 and Sample 2 show strong ultraviolet emission peaks centered at 360nm and 354nm, respectively. Thermal gravimetric analysis (TGA) curves reveal that the thermal stability (against air oxidation) of Sample 2 is better than Sample 1. The possible formation mechanisms of the products with distinct dimensions were briefly discussed. [Copyright &y& Elsevier]

Abstract: Rare-earth hexaborides (RB6, R=Ce, Pr, Nd) nanocrystals were prepared by a facile solid state reaction in an autoclave. Single-crystalline RB6 nanocubes were fabricated at 500°C starting from B2O3, RCl3·6H2O and Mg powder. RB6 nanoflakes and nanoparticles could be obtained around 400°C using NaBH4 as boron resource. XRD patterns show that all of the hexaborides are cubic phase with high crystallinity and high purity and have lattice parameters that are consistent with nearly stoichiometric products. Raman spectra elucidate the active vibrational modes of the hexaborides. The TEM and FESEM images clearly show that the nanocubes have an average size of 200nm and nanoparticles of 30nm. Our experiment developed an efficient, simple and low-cost route to prepare RB6, which could be extended further to the preparation of other rare-earth metal hexaborides. [Copyright &y& Elsevier]

Abstract: Silicon carbide (3C-SiC) nanocrystals were prepared starting from SiO2, C2H5OH, and metallic Mg in an autoclave at 200°C. X-ray diffraction patterns of the sample can be indexed as the cubic phase of SiC with the lattice constant a =4.357Å, in good agreement with the reported value (JCPDS card no. 29-1129; a =4.359Å). Transmission electron microscopy images show that the product mainly composed of nanowires with diameters in the range of 10–30nm and lengths up to tens of micrometers; High-resolution transmission electron microscopy images reveal that these 3C-SiC nanowires grow along [111] direction; As polyvinylpyrrolidine was added into the above reactant system, the final products obtained at 180°C were mixed 3C and 2H-SiC flakes. Thermal gravimetric analysis curves reveal that these two samples have thermal stability below 800°C, and room-temperature photoluminescence spectrum of the 3C-SiC sample show a strong emission peak centered at 403nm. [Copyright &y& Elsevier]

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: 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]

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]

Abstract: The spherical ZnS and flower-like CdS microcrystallites are prepared by a convenient hydrothermal process through the reactions of Zn(CH3COO)2·2H2O or Cd(CH3COO)2·2H2O with S and NaH2PO2·H2O in aqueous solution at 180 °C for 12 h. Powder X-ray diffraction (XRD) is used to confirm the cubic phases of the ZnS and CdS microcrystallites. Their chemical compositions are characterized by X-ray photoelectron spectroscopy (XPS). Scanning electron microscope (SEM) images show the morphologies of the as-synthesized ZnS and CdS. The photoluminescence spectra (PL) exhibit their optical properties. [Copyright &y& Elsevier]

Abstract: V2O3 and VN nanocrystals have been synthesized by the decomposition of the precursor NH4VO3 and following nitridation in an autoclave with metallic Na flux at 450–600°C. X-ray powder diffraction (XRD) recorded the evolution process of the reaction from precursor NH4VO3 to hexagonal V2O3 and then to NaCl-type VN. In addition, the products were characterized by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). [Copyright &y& Elsevier]

Abstract: Stable (α) MnS was synthesized by solvothermal method in different solutions at relatively low temperature (120°C for 12h). The effect of the solvents, surfactant, the ratio of reactant to the surfactant and reaction temperature, time on the morphology and phase of products has been investigated. The morphology of the products was mainly affected by the solvent and the concentration of the surfactant. The as-prepared α-MnS crystals have been characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV–vis absorption and the PL spectrum and X-ray photoelectron spectroscopy (XPS). The proposed formation mechanism of α-MnS is also discussed. [Copyright &y& Elsevier]

Abstract: Single-crystalline nanorods of β-MnO2, α-Mn2O3 and Mn3O4 were successfully synthesized via the heat-treatment of γ-MnOOH nanorods, which were prepared through a hydrothermal method in advance. The calcination process of γ-MnOOH nanorods was studied with the help of Thermogravimetric analysis and X-ray powder diffraction. When the calcinations were conducted in air from 250 to 1050°C, the precursor γ-MnOOH was first changed to β-MnO2, then to α-Mn2O3 and finally to Mn3O4. When calcined in N2 atmosphere, γ-MnOOH was directly converted into Mn3O4 at as low as 500°C. Transmission electron microscopy (TEM) and high-resolution TEM were also used to characterize the products. The obtained manganese oxides maintain the one-dimensional morphology similar to the precursor γ-MnOOH nanorods. Further experiments show that the as-prepared manganese oxide nanorods have catalytic effect on the oxidation and decomposition of the methylene blue (MB) dye with H2O2. [Copyright &y& Elsevier]

Abstract: Nanocrystalline vanadium nitride (VN) was prepared by a direct thermal liquid–solid reaction between vanadium chloride (VCl4) and sodium azide (NaN3) at 600 °C. Characterized by XRD, TEM, XPS and PL, the composition and morphology of the product were confirmed. The possible reaction mechanism was also discussed. [Copyright &y& Elsevier]

Abstract: Crystalline silver nanowires, with diameters of 100–500 nm and lengths up to tens of micrometer, were synthesized via a reaction of Cu2O and AgNO3 in aqueous solution mixed with ethanol at room temperature. Cu2O was used as reducing agent. The samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanism for the formation of silver nanowires is discussed. [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]

Vanadium nitride was synthesized by the reaction of VCl4 and NaNH2 at room temperature. X-ray powder diffraction could be indexed as cubic VN with the lattice constant of a=4.134Å. Transmission electron microscopy image showed particle and hollow sphere morphology. The optical properties of the as-prepared VN were investigated. [Copyright &y& Elsevier]

Nanocrystalline silicon carbide has been prepared via reacting magnesium silicide (Mg2Si) with carbon tetrachloride (CCl4) in an autoclave at 450–600°C. X-ray diffraction patterns of the products can be indexed as the cubic cell of SiC with the lattice constant, a=4.352 Å, in good agreement with a=4.349 Å (JCPDS card No. 75-0254). The transmission electron microscopy images show that the sample mainly consists of nanoparticles with an average size from 30 to 80 nm co-existing with a small fraction of nanorods and nanowires. Typically the nanorods range from 20 to 40 nm in diameter and the nanowires have diameters of 20 nm and lengths up to 10 μm. The Raman spectrum shows a characteristic sharp peak at 790 cm-1. X-ray photoelectron spectra (XPS) gives an atomic ratio of Si to C as 1.08:1.00 from the quantification of the peak intensities. Photoluminescence spectrum reveals that the SiC sample emits ultraviolet light of 328 nm. A possible mechanism and the influence of temperature on the formation of crystalline SiC are proposed. [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]

Chromium silicide (Cr3Si) nanorods were successfully synthesized using anhydrous chromium trichloride and silicon tetrachloride as starting materials via a co-reduction route at 600 °C in an autoclave. X-ray powder diffraction pattern indicated that the product was cubic Cr3Si (a=4.555 Å). Transmission electron microscope images indicated that the sample consisted of single-crystalline nanorods with a diameter of 40–80 nm, an average length of about 600 nm and a maximum length of about 1.0 μm. The oxidation of Cr3Si began to proceed at the temperature of 650 °C in air, but the product had a high thermal oxidation stability below 1000 °C due to the formed protective layer. [Copyright &y& Elsevier]

Ultrafine magnesium diboride (MgB2) powders were successfully synthesized at 600 °C through a solid-state reaction. The synthesis was carried out in an autoclave by using MgCl2 and NaBH4 as the reactants. The X-ray powder diffraction pattern indicates the formation of hexagonal MgB2. Transmission electron microscopy image shows that typical MgB2 crystallites are composed of ultrafine particles with an average size of 300 nm. The superconducting transition of the MgB2 sample occurs at 39 K. [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]

Boron nitride hollow spheres were synthesized by the reaction of BBr3 and NaNH2 at room temperature; X-ray powder diffraction pattern could be indexed as hexagonal BN with the lattice constants of a=2.482 and c=6.701 A˚; high-resolution transmission electron microscopy image showed the hollow spheres consisted of BN nanoparticles, with diameter between 80 and 300 nm; a possible formation mechanism of BN hollow spheres was discussed. [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]

Nanocrystalline hafnium diboride (HfB2) has been prepared by the reaction of HfCl4 with NaBH4 at 600 °C in an autoclave. The X-ray powder diffraction (XRD) pattern can be indexed as hexagonal HfB2 with the lattice constants of a=3.146 and c=3.456 A˚. The transmission electron microscopy (TEM) image shows a particle morphology with an average size of 25 nm. The selected area electron diffraction (SAED) pattern confirms the presence of hexagonal HfB2. The oxidation behavior of HfB2 is studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). [Copyright &y& Elsevier]

VOx·nH2O (2.0⩽x⩽2.5) nanoribbons have been synthesized by direct hydrothermal processing of the aqueous solution of NH4VO3 and polyethylene glycol 400 (PEG-400) at pH 3.5–5.5. Techniques of XRD, SEM, TEM, HRTEM, ED, and XPS have been used to characterize the structure, morphology, and composition of the nanoribbons. The VOx·nH2O nanoribbons are up to ∼200 μm in length, 100–150 nm in width, 20–30 nm in thickness, and grow along the [010] direction. The ratios of V4+ to V5+ in the products can be readily controlled by carefully adjusting the periods of reaction time. PEG carries the roles of both transport and reducing agent. A coordination self-assembly mechanism was proposed to elucidate the formation of the VOx·nH2O nanoribbons. [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]

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]

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]

Metal sulfides MS (M=Cd, Zn, Co, Pb, Cu), M2S3 (M=Bi, Sb), M2S (M=Ag) were successfully synthesized through a one-step reaction between metal salts and thiourea in ethylene glycol (EG) under the microwave irradiation. The products were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS), transmission electron microscope (TEM) and electron diffraction (ED). [Copyright &y& Elsevier]

Carbon nanotubes were synthesized via a single-source precursor route at 500 °C, using iron carbonyl both as carbon source and catalyst. The X-ray power diffraction pattern indicates that the products are hexagonal graphite. Transmission electron microscope (TEM) images of the sample reveal carbon nanotubes with an average inner (outer) diameter of 30 nm (60 nm). High-resolution TEM indicates that fabrication of the carbon nanotube walls was composed of ca. 40 graphene layers. The Raman spectrum shows two strong peaks at 1587 and 1346 cm−1, corresponding to the typical Raman peaks of graphitized carbon nanotubes. This method avoids the separation of raw material from solvent and simplifies the operation process. At the same time, the research provides a new route to large-scale synthesis of carbon nanotubes. [Copyright &y& Elsevier]

SnS2 films have been deposited on glass and alumina plate substrates by the reactions between an organotin precursor [tetrabuyltin, (CH2CH2CH2CH3)4Sn] and carbon disulfide in n-hexane at the temperature range 180–200 °C for 10–40 h. The reaction system was oxygen free and applied at a moderate temperature. The films so prepared were characterized by techniques of X-ray diffraction, Scanning electron microscopy, Raman and Mo¨ssbauer spectroscopies. The films deposited on glass as well as on alumina plate have an average thickness of 30 μm, but have different rose-like morphologies, which are influenced by both the anisotropic growths of crystals and the different substrate structures. Photoluminescence measurements show that the films have an emission peak at approximately 590 nm. [Copyright &y& Elsevier]

The synthesis and characterization of hollow nanospheres, nanowires and coaxial nanowires of cubic phase silicon carbide (β-SiC) were reported. The reaction between SiCl4 (or Si powders), C6Cl6 and sodium was used to prepare SiC nanostructures at different temperature. The samples were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), high-resolution transmission electron microscopy (HRTEM), Raman, photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS) procedures. Studies found that temperature and reagents were key factors for the samples’ morphologies. [Copyright &y& Elsevier]