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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: 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: 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]

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]

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]

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]

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 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: 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]