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Abstract: A new method for synthesis of nanocrystalline titanium nitride was developed through the reaction of titanium oxide and sodium amide at 500–600 °C for 12 h in an autoclave. X-ray diffraction (XRD) and electron diffraction (SAED) results indicated the product had a cubic phase with lattice parameter a =4.242 Å. Transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) revealed that the particle sizes were 10 to 40 nm. Quantitative analysis using X-ray photoelectron spectrum (XPS) showed the atomic ratio Ti:N was 1.03:1. [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]

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]

Abstract: Nanocrystalline neodymium disilicide was synthesized by co-reducing anhydrous neodymium trichloride and sodium fluorosilicate with metallic sodium in an autoclave at 650°C. The as-prepared product was characterized and studied by X-ray powder diffraction, transmission electron microscopy and thermogravimetric analysis. [Copyright &y& Elsevier]

Nanocrystalline vanadium diboride (VB2) were successfully synthesized at 650 °C through a solid state reaction. The synthesis was carried out by reacting VCl4 with NaBH4 and Mg in an autoclave. The X-ray powder diffraction pattern indicates the formation of hexagonal VB2. An atomic ratio of B to V of 2.11:1.0 is determined from X-ray photoelectron spectra. Transmission electron microscopy image shows that typical VB2 crystallites are composed of uniform particles with the grain size in the range of 50–100 nm. [Copyright &y& Elsevier]