Preparation and thermal stability of Eu2O3-doped Al2O3 nanometer-sized powder using the modified bimetallic alkoxides

The Eu-doped nanostructured alumina powder could be synthesized by the sol-gel, process using the mixtures of bimetallic alkoxide Eu[Al(OPr')(4)](3) and Al(OPr')(3) as precursors. The derived gels remained amorphous below 900degreesC. At the composition of 1 mol % Eu2O3-doped alumina, the spherically shaped amorphous alumina and alpha-Al2O3 powders with a mean size of 8, and 30nm. were also obtained. It was shown that the Eu3+ dopant not only can be totally dispersed in the alumina matrix, but also leads to the high thermal stability of the Eu-doped alumina nanosized powder With a suitable amount of Eu2O3 due to the incoherent boundary formation. The specific surface area and the apparent density were decreased with an increase of the high crystallinity 617 the crystalline phases. It was also found that the addition of 1 mol % Eu2O3 was most effective not only to sustain high thermal stability at high temperatures, but also for the gamma-Al2O3 single phase to exist stably when the calcining temperature was kept in the range of 900-1100degreesC. (C) 2003 Elsevier B.V. All rights reserved.