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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]

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 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 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]