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Abstract Hollow spheres, hollow capsules and solid spheres of carbon were selectively synthesized by Mg-reduction of hexachlorobutadiene at appropriate reaction conditions. X-ray powder diffraction and Raman spectra reveal that the as-prepared materials have a well-ordered structure. A possible formation mechanism has been proposed.

A silicon hierarchical structure composed of 20 nm Si nanoparticles (Si-20) is synthesized using a solvothermal method. After coating with a carbon layer by pyrolysis of acetylene gas, the fabricated Si-20@C composites exhibit a superior cycling performance with 915.8 mA h g−1 at 3.6 A g−1 over 500 cycles and a high rate performance with 746.2 mA h g−1 at 10.8 A g−1. [ABSTRACT FROM AUTHOR]

Hollow structures of transition-metal oxides, particularly mixed-metal oxides, could be promising for various applications such as lithium-ion batteries (LIBs). Compared to the synthesis of metal oxide hollow spheres by the template method, non-spherical metal oxide hollow hexagonal polyhedra have not been developed to date. Herein, we report the controlled hydrothermal synthesis of a new phase of Co3V2O8⋅ n H2O hollow hexagonal prismatic pencils (HHPPs), which is composed of uniform structural units. By varying the amount of NaOH in the presence of NH4+ and without any template or organic surfactant, the hexagonal prismatic pencils gradually transform from solid into hollow structures, with sizes varying from 5 to 20 μm. The structure of pencils can be preserved only in a limited range of the molar ratio of OH−/NH4+. As a new anode material for LIBs, such hollow pencils exhibit impressive lithium storage properties with high capacity, good cycling stability, and superior rate capability. [ABSTRACT FROM AUTHOR]

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]

Abstract In this study, silicon (Si) nanoparticles have been prepared by a chemical reaction of calcium silicide (CaSi 2), sulfur and metallic sodium in an autoclave at 250 °C. X-ray powder diffraction pattern indicates that the obtained sample is cubic phase Si with the calculated lattice constant a = 5.436 Å. Electron microscopy images show the obtained Si sample is composed of nanoparticles with an average size of 50 nm. As an anode for lithium ion batteries, the as-prepared Si nanoparticles exhibit a reversible capacity of 1409 mA h g−1 at a current density of 2 A g−1 over 300 cycles. Highlights • Si nanoparticles are synthesized at a low temperature. • The obtained Si nanoparticles exhibit high capacity and excellent rate capacity. • Si nanoparticles exhibit a reversible capacity of 1409 mAh g−1 over 300 cycles. [ABSTRACT FROM AUTHOR]

Abstract: In order to explore how to improve the electrochemical performance of the lead-acid battery positive active material, PbO2 particles with multiple morphologies and phases including urchin-like and ball-like β-PbO2 particles with size of 0.5–1 μm, flower-like α-PbO2 particles with size of 1–2 μm are chemically synthesized. These samples are composed of different smaller nanoparticles. The electrode made with urchin-like β-PbO2 and flower-like α-PbO2 in the ratio of 1:1 can deliver a discharge capacity of 183 mA h g−1 at 0.1 C after 100 cycles, and subsequent rate performance test shows that a discharge capacity of 97.2 mA h g−1 can be obtained even at 1 C. Moreover, this kind of electrode pretreated in 1 M H2SO4 solution displays improved stability of cycle, a capacity of 146.7 mA h g−1 can be obtained after 100 cycles, and its corresponding active material utilization ratio can reach 65%. [Copyright &y& Elsevier]

Nitrogen-doped carbon (NC) materials were prepared by pyrolyzing pyrrole in the presence of basic magnesium carbonate at 400–700°C. Three kinds of C–N bonding patterns, namely pyridinic-, pyrrolic-, and graphitic-type N, are present in NC products. The pyrolysis temperature has an intensive influence on the contents of three nitrogen species. It is found that NC-700, containing the highest content (3.87at%) of graphitic-type N, exhibits the best discrimination ability for ascorbic acid (AA), dopamine (DA), and uric acid (UA). Differential pulse voltammetry study reveal that the detection limit (S/N=3) can reach 0.090µM for DA even in the presence of 1000µM AA and 200µM UA. [ABSTRACT FROM AUTHOR]

Abstract: Uniform nanospherical Li2MnSiO4/C/graphene composites have been obtained by polyethylene glycol-600 (PEG-600) assisted solid-state reaction using spherical SiO2 as precursor, and heat treatment with the mixed carbon sources (glucose, cellulose acetate and graphene oxide). The transmission electron microscope (TEM) images show that Li2MnSiO4 nanospheres with size of 50 nm are embedded in the three-dimensional (3D) nest-like carbon network. Electrochemical measurements reveal that the composites exhibit first discharge capacity of 215.3 mAh g−1 under 0.05 C, together with a stable discharge capacity of 175 mAh g−1 after 40 cycles. The 3D carbon network and the carbon layer (amorphous carbon and graphene) are favorable for improving the electrochemical performance. [Copyright &y& Elsevier]

Abstract: Starting from waste polytetrafluoroethylene (PTFE), metal oxides (TiO2, V2O5, Nb2O5, and MoO3) and metal sodium, several nanocrystalline transition metal carbides (TiC, VC, NbC, and Mo2C) have been prepared through a thermal reduction route in an autoclave at 600 °C. It is found that the obtained NbC nanocrystallines have a superconducting transition temperature at 11.6 K. [Copyright &y& Elsevier]

Abstract: MnCO3 microstructures, including 2.3μm microplates with the thickness of 200nm and 3.1μm microspheres stacked with 50nm-thick sheets, were hydrothermally prepared in the assistance of sodium dodecyl benzene sulphonate (SDBS) and dodecyl sulfonic acid sodium (SDS), respectively. With the as-synthesized MnCO3 as precursors followed by annealing at 400°C for 4h, mesoporous γ-MnO2 microplates and microspheres with the pore size of 4–50nm, which basically preserved the initial shapes, were obtained. The Brunauer–Emmett–Teller surface areas of the as-prepared γ-MnO2 microplates and microspheres were 52.1m2 g−1 and 50.2m2 g−1, respectively. The electrochemical property tests over Li+ batteries showed that the initial discharge capacity of γ-MnO2 microplates and microspheres were 1997mAhg−1 and 1533mAhg−1. Noticeably, even after 100cycles, the discharge capacity of γ-MnO2 microplates was still as high as 626mAhg−1, indicating the decent cycle behavior. In addition, mesoporous γ-MnO2 was also applied as adsorbents in water treatment, and γ-MnO2 microplates and microspheres could remove about 55% and 80% of Congo red. [Copyright &y& Elsevier]

Abstract: The phase transition of CdSe nanocrystallines from zinc blende to wurtzite phase can be controlled by varying the volume ratio of ethanolamine (EA) and water (WA) in their mixed solution and the morphologies of the CdSe nanocrystals are controlled simultaneously. The phase transition has been demonstrated by XRD patterns and HRTEM images. The samples are investigated by Raman spectrum. The Raman shifts of the samples show a gradual blue shift with the gradual transformation from zinc blende to wurtzite CdSe phase. This method is convenient and controllable which can provide a strategy way to control the phase and morphology of the nanomaterials and study their phase transitions in nanoscale field. [Copyright &y& Elsevier]

Abstract: ZnO nanowires (∼60%) and nanobelts (∼40%) have been fabricated on a large scale via a low temperature one-pot hydrothermal technique. Na2CO3 was introduced not only as alkaline source but also as a controllable reagent for the crystal growth of ZnO. The comparison experiment results indicate that the adding amount of Na2CO3 greatly affect the length/diameter aspect ratios of 1D ZnO nanocrystals. In addition, the introduction of surfactant SDSN was indispensable in controlling the growth of belt-like ZnO. Room temperature photoluminescence spectrum showed a weak UV band emission at 379nm and a strong broad yellow emission around 564nm. A possible mechanism on the formation of the ZnO nanowires was proposed. [Copyright &y& Elsevier]

Abstract: Novel flower-like pattern of radially aligned ZnSe nanoflakes were synthesized via a facile solvothermal method in a mixed solvent of ethylenediamine and hydrazine hydrate. XRD, FESEM and TEM characterizations showed that as-prepared ZnSe sample is metastable wurtzite phase and the nanoflakes have uniform thickness of about 60nm. The PL spectrum of the as-prepared sample was investigated. The formation conditions of the flower-like pattern of radially aligned ZnSe nanoflakes were discussed and it was found that the ratios of the solvent components are of great importance for the final formation of the flower-like structures. [Copyright &y& Elsevier]

Abstract: Triazine-based nitrogen-rich graphitic carbon nitrides have been synthesized via two routes based on polycondensation reaction between melamine and cyanuric chloride in presence of nickel powder. The first route is a solvothermal method using benzene as solvent. The second one is a solvent-free solid reaction route. X-ray diffraction (XRD) patterns indicated that the synthesized products are graphite-like carbon nitride. Transmission electron microscopy (TEM) images reveal that the products mainly consist of 10–40nm hollow spheres. The high atomic N/C ratio (1.60) determined by bulk element analysis shows the products are nitrogen-rich carbon nitrides. The chemical bonding structure and optical properties of the carbon nitride materials have been investigated by Fourier transform infrared spectroscopy (FTIR), Ultraviolet visible spectroscopy (UV–vis), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). The experimental results show that the products reserve the s-triazine structure. Both the products display the broad violet peak emission at about 408nm. [Copyright &y& Elsevier]

Abstract: ZnS hollow nanospheres have been hydrothermally synthesized at 200°C for 4h. In same condition ZnS microspheres were obtained when using acrylamide as the surfactant. XRD pattern indicates as-prepared sample is cubic ZnS with cell constant a =5.391Å and the average size of ZnS particles was 6.5nm estimating from the Debye–Scherrer formula. TEM observed the hollow nanospheres have the diameters ranging from 200 to 300nm with a shell thickness of about 40nm. UV–vis and PL spectra recorded the optical properties of the sample, a blue-shift (∼19nm) was observed. It appears that the hollow spheres might be formed by soft-template of gas bubbles of SO2 produced during the reaction. [Copyright &y& Elsevier]

Abstract: The cubic β-In2S3 hollow nanospheres was fabricated via two-step solvothermal approaches using InCl3·4H2O, CS2, and thioacetamide (C2H5NS) as the starting materials. The as-prepared cubic β-In2S3 possessed hollow nanosphere structures, whose outward diameters and shells are −75 and 20nm, respectively. The samples were characterized by XRD, FESEM, TEM, SAED, and HRTEM. The optical properties of the cubic β-In2S3 hollow nanospheres were also investigated. UV–vis (280nm) and PL (367nm) spectra indicate that there exists obvious blue shift compared with the In2S3 bulk materials. [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: Zn-doped Ni nanotubes with wall thickness in the range of 10–20 and 100–200nm in inner diameter have been synthesized in ethanol via a room-temperature solution synthetic route. Powder X-ray diffraction (XRD) pattern shows that the as-synthesized particles have a chemically disordered fcc structure. The coercivity of the products was investigated to be 515.6Oe at room temperature. The catalytic property of Zn-doped Ni nanotubes was also conducted. [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: One-dimensional (1D) nanostructured materials, chromium nitride (CrN) nanorods have been prepared initially via a direct thermal solid-state reaction of anhydrous chromium(III) tetrachloride (CrCl3) and sodium azide (NaN3) at a temperature of 600°C for 12h. The X-ray diffraction pattern of the product is indexed as cubic CrN. Transmission electron microscope images indicate that the sample consists of CrN nanorods with the diameters of 40–60nm and lengths in the range of 500nm to 1μm. X-ray photoelectron spectroscopy (XPS) results show the mole ratio of Cr:N as 1.15:1. The possible reaction mechanism is also discussed. [Copyright &y& Elsevier]

Abstract: Nanocrystalline Mo2C powders were successfully synthesized at 500°C by reacting molybdenum chloride (MoCl5) with C (graphite or carbon nanotube) in metallic sodium medium. X-ray powder diffractometer (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscope (XPS) and surface area analyzer (BET method) were used to characterize the samples. Experiments reveal that the carbon source used for the carbide synthesis has a great effect on the particle size and the surface area of the samples. When micro-sized graphite was used as C source the obtained nanocrystalline Mo2C powder consists of particles of 30∼100nm, with a surface area of 2.311m2/g. When carbon nanotubes were used as C source, the as-synthesized Mo2C sample is composed of particles of 20∼50nm, with a surface area of 23.458m2/g, which is an order of magnitude larger than that of the carbide prepared from the graphite. [Copyright &y& Elsevier]

Abstract: Antimony dendritic nanocrystals have been prepared in a large scale by the reduction of Sb3+ with metallic zinc powder at room temperature in aqueous or alcoholic solution. It is found that homogeneous Sb3+ solution and rapid reduction reaction play important role in the formation of Sb dendrites. The possible formation mechanism of Sb dendrites is also investigated. [Copyright &y& Elsevier]

Abstract: A complex reaction route was developed for the preparation of flower-like cobalt nanocrystals by using 2-hydroxy-4-(1-methylheptyl) benzophenone oxime (N530), a normally effective chelate extracting agent. X-ray powder diffraction pattern shows that the cobalt nanocrystals coexist of both hexagonal close-packed (hcp) and cubic close-packed (ccp) forms, with flower-like architecture characterized by a field emission scanning electronic microscopy. The magnetic coercivity Hc of the as-prepared cobalt crystals came up to 360Oe at room temperature. The existence of the precursor N530–CoCl2 complex was determined by a Fourier transform infrared (FT-IR) spectrometer. Experiments suggested that the existence and the framework structure of the precursor complex have a considerable effect on the final architectures of cobalt nanocrystals. [Copyright &y& Elsevier]

Abstract: Potassium nickel fluoride (KNiF3) hollow spheres with diameters of 200–400nm have been solvothermally synthesized at 110°C using KF and NiCl2 as reactants in ethanol, without additional template materials or surfactants. The results of XRD and XPS indicate that the products are perovskite-type KNiF3. TEM microphotos show that the hollow spheres are composed of KNiF3 nanoparticles with an average size of 10nm, and the wall thickness is 20–40nm. UV–vis and PL spectra have recorded the optical properties of KNiF3 hollow spheres. A possible mechanism for the formation of KNiF3 hollow spheres is also discussed. [Copyright &y& Elsevier]

Titanium silicides were synthesized by co-reducing silicon tetrachloride and titanium tetrachloride with different metal reductants (Na, Mg, Zn and Al) in an autoclave at 650 °C. The X-ray diffraction patterns indicated that the obtained titanium silicides could adopt different structures. The orthorhombic titanium disilicide was obtained when the reductant was metallic sodium. However, the hexagonal titanium silicide (Ti5Si3) was obtained when using Mg, Zn and Al. Transmission electron microscope images showed that the average particle sizes of the samples were about 60, 40, 30 and 25 nm in diameters, respectively. It is suggested that the different reaction activities of the reductants resulted in the different titanium silicides. [Copyright &y& Elsevier]

High-quality binary sulfides WS2, MoS2, and V5S8 have been prepared via a direct sulfidization route from the respective oxides, using NH3·H2O and CS2 as starting materials to produce H2S acting as sulfur source. Characterizations by X-ray powder diffraction and X-ray photoelectron spectra suggest that all three sulfides have the pure phases and stoichiometric compositions as expected. Flaky WS2 and V5S8 with irregular shapes are determined by transmission electron microscopy. In particular, MoS2 submicrometer spheres with the yield of ca. 100% are observed by field-emission scanning electron microscopy. It is found that the reaction temperature plays an important role in the reaction system. A possible mechanism is 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]

Elegant 3D SnS urchin-like architectures have been successfully prepared using SnCl2·2H2O and KSCN as starting materials in ethylene glycol under a mild solvothermal condition. The morphological transformation from 3D frameworks into 1D nanostructures has been observed, which were strongly dependent on the prolonged reaction time. The prepared products were characterized by various techniques, such as XRD, XPS, FESEM, TEM and ED. The possible formation mechanism was also discussed. [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]

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]

Nanocrystalline boron nitride (BN) with needle-like and hollow spherical morphology has been synthesized by nitriding of MgB2 with NH4Cl and NH4Cl–NaN3, respectively. The amount of NaN3 has an obvious effect on the size of the hollow spheres. The samples were characterized by X-ray powder diffraction, Fourier transformation infrared spectroscopy, X-ray photoelectron spectra, and transmission electron microscopy. The possible mechanism of morphology control is also discussed. [Copyright &y& Elsevier]

The growth of crystalline Sb2Se3 whiskers has been conducted via a hydrothermal process. It was found that the organic additives added to the hydrothermal system had important influence on the growth behavior of Sb2Se3 whiskers. The structure features of Sb2Se3 whiskers were characterized by scanning electron microanalyzer and X-ray diffraction (XRD) techniques. The growth mechanism was discussed and the relationship between crystal morphologies and the crystal structure of Sb2Se3 were discussed. [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]

Nanocrystalline lead chalcogenides PbE (E=S, Se, Te) were synthesized conveniently by the reaction of Pb(CH3COO)2·3H2O and elemental chalcogens in ethylenediamine (en) under ultrasonic irradiation. XRD and TEM techniques were employed to characterize the products. The solubility of chalcogen in en was found to be the key factor of the reaction. A three-step mechanism was proposed to account for the formation of the 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: ZnCO3 nanoparticle aggregations with porous morphology are prepared via a facile solid-state metathesis reaction in ambient environments. For the first time, ZnCO3 is characterized as a novel anode material for lithium-ion batteries. The porous ZnCO3 delivers an initial reversible capacity of 735mAhg−1 and good rate ability. The good electrochemical performance can be attributed to its unique hierarchy architecture, which facilitates the ion transport and buffers the large volume change during the alloying/de-alloying reactions. [Copyright &y& Elsevier]

Abstract: Nanocrystalline ZrC has been prepared via a convenient route by the reaction of metallic magnesium powder with zirconium oxide and lithium carbonate in an autoclave at 600°C. X-ray powder diffraction pattern indicated that the product was cubic zirconium carbide, and the cell constant was a =4.693Å. Scanning electron microscopy (SEM) image showed particles with an average size of about 30nm. The product was also studied by thermogravimetric analysis (TGA). It had good oxidation resistance below 250°C in air. [Copyright &y& Elsevier]

Abstract: Flower-like microstructures of ferromagnetic Ni nanotips have been synthesized in aqueous solution at 140 °C for 12 h. XRD pattern indicated the sample is cubic Ni with lattice constant a =3.514 Å. FE-SEM shown the formation process of Ni sample. Room temperature magnetic characterization of as-prepared Ni sample demonstrates much enhanced ferromagnetic property. The hydrazine hydrate was used as reduced agent and ligand in present synthesis, the possible formation mechanism was also discussed. [Copyright &y& Elsevier]

Abstract: Nanocrystalline chromium nitride (CrN) has been synthesized by reacting metallic chromium (Cr) powder with sodium azide (NaN3) at the temperature range of 450–550°C. The samples were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectra (XPS) and transmission electron microscopy (TEM). This work shows that it is very simple to synthesize CrN nanocrystalline and opens a wide route towards synthesis of other metallic nitrides. [Copyright &y& Elsevier]

Graphite sheets have been synthesized by using hexachlorobutadiene (C4Cl6) and Na as reactants at 500 °C in an autoclave. Transmission electron microscopy images show that the average dimension of graphite sheets is about 8 × 15 μm and the thickness ranges 20–50 nm. The possible reaction mechanism is discussed. [Copyright &y& Elsevier]

Amorphous phosphorus nitride (P3N5) hollow spheres were synthesized via reacting PCl3 with NaNH2 at room temperature. Transmission electron microscopy (TEM) images showed the hollow spheres with a diameter of 80–150 nm. X-ray photoelectron spectra (XPS) were used to determine the molar ratio of 1:1.60 for P:N. The optical properties of the as-prepared P3N5 were investigated. [Copyright &y& Elsevier]

Nanocrystalline titanium diboride (TiB2) powders were successfully synthesized at 650 °C by using TiCl4, Mg and MgB2 as the reactants. Transmission electron microscopy images show that typical TiB2 crystallites are composed of uniform particles with the average grain size of about 40 nm. [Copyright &y& Elsevier]