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Abstract: One-dimensional (1D) nanostructured materials, chromium nitride (CrN) nanorods have been prepared initially via a direct thermal solid-state reaction of anhydrous chromium(III) tetrachloride (CrCl3) and sodium azide (NaN3) at a temperature of 600°C for 12h. The X-ray diffraction pattern of the product is indexed as cubic CrN. Transmission electron microscope images indicate that the sample consists of CrN nanorods with the diameters of 40–60nm and lengths in the range of 500nm to 1μm. X-ray photoelectron spectroscopy (XPS) results show the mole ratio of Cr:N as 1.15:1. The possible reaction mechanism is 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]

Chromium boride (CrB) nanorods were synthesized via a reduction–boronation route at 650 °C in molten salt in an autoclave. The X-ray diffraction pattern of the product was indexed as the orthorhombic CrB. Transmission electron microscope images indicated that the sample consisted of single-crystalline nanorods with the diameter of 10–30 nm and a maximum length of 1.5 μm. The PL spectra showed the ultraviolet light emission at 340 nm. The thermogravimetric analysis showed that the product also had very good anti-oxidation properties below 630 °C. A possible growth mechanism was proposed. [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]