Synthesis and characterization of zirconia doped alumina nanopowder by citrate-nitrate process

Al2O3-ZrO2 nanopowders containing 5-20 wt.% ZrO2 was synthesized by a simple aqueous sol-gel method using a citrate polymeric precursor derived from aluminium nitrate, zirconium oxychloride and citric acid mixed solution. The thermal decomposition of the precursor and subsequent formation of alpha-Al2O3 was investigated by differential thermal analysis. X-ray diffraction analysis shows that the phases present at 1200 degrees C are alpha-Al2O3 and t-ZrO2 irrespective of zirconia content. The t-ZrO2 is found to increase with increase in zirconia content. FTIR also confirms the formation of alpha-Al2O3 incorroboration with X-ray studies. TEM micrograph of calcined powder revealed nanosize spherical particle of similar to 75 mn. EDAX confirmed the presence of alumina and zirconia particle in the nanopowder calcined at 1200 degrees C. (C) 2007 Elsevier B.V. All rights reserved.