The effect of starch addition on solution combustion synthesis of Al2O3-ZrO2 nanocomposite powder using urea as fuel

The present article reports the results of studies related to the synthesis of Al2O3-ZrO2 nanocomposite powder by solution combustion process using modified fuels containing urea and starch. A thermodynamic modeling was used to theoretically predict the effect of fuel composition on the exothermicity of the combustion synthesis process. To characterize the products, X-ray diffractometry, TEM, SEM, surface area analysis, BET, and differential thermal analysis (DTA) were used. It is shown that employment of a starting solution with fuel based on urea modified with 5% starch as an excess fuel, decrease exothermicity of the combustion reaction and results in synthesizing nanostructured Al2O3-ZrO2 powder mixture with small crystallite size (<20 nm) and fine agglomerates in a way that specific surface area up to 13.16 m(2) g(-1) could be obtained. (C) 2007 Elsevier B.V. All rights reserved.