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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]

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]

Abstract: Niobium diboride (NbB2) nanorods have been successfully synthesized by the reaction of NbCl5 with NaBH4 in the temperature range of 550–650 °C in an autoclave. X-ray diffraction (XRD) and electron diffraction show that the as-prepared products are NbB2. Transmission electron micrographs shows that the average diameter of samples are in the range of 50–60 nm and the length is up to 600 nm. The mechanism for the formation of crystalline NbB2 is proposed. [Copyright &y& Elsevier]