One simple synthesis route to nanocrystalline tantalum carbide via the reaction of tantalum pentachloride and sodium carbonate with metallic magnesium

Nanocrystalline tantalum carbide (TaC) was synthesized via a simple route by the reaction of metallic magnesium with sodium carbonate and tantalum pentachloride in an autoclave at 600 degrees C. X-ray powder diffraction pattern indicated that the product was cubic TaC, and the cell constant was a = 4.451 angstrom. Field emission scanning electron microscopy image showed that it consisted of particles with an average size of 40 nm. The product was also studied by TGA in the flowing air. It had good thermal stability and oxidation resistance below 450 degrees C in air. The mechanism of the formation of TaC was also discussed in this paper. (C) 2006 Elsevier B.V. All rights reserved.