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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]

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]