Carbothermal synthesis of ultra-fine zirconium carbide powders using inorganic precursors via sol-gel method

Ultra-fine zirconium carbide (ZrC) powders have been synthesized by carbothermal reduction reactions using inorganic precursors zirconium oxychloride (ZrOCl2 center dot 8H(2)O) as sources of zirconium and phenolic resin as the carbon source. The reactions were substantially completed at relatively lower temperatures (similar to 1400 degrees C/1 h) and the synthesized powders had a small average crystallite size (<200 nm) and a large specific area (54 m(2)/g). The oxygen content of the powder synthesized at 1400 degrees C/1 h was less than 1.0 wt%. The thermodynamic change process in the ZrO2-C system and the synthesis mechanism were studied.