Synthesis of monodisperse nanocrystalline 8 mol-% yttria doped ceria powder by oleate complex route

Abstract

Preparation of monodisperse nanocrystalline yttria doped ceria powder by the oleate complex route has been reported. Y(III) and Ce(III) oleate complexes have been prepared by the reaction between YCl₃, Ce(NO₃)₃ and sodium oleate at the interface of hexane rich and water rich conjugate layers of water-ethanol-hexane ternary liquid system. Cubic yttria doped ceria crystallises when the waxy solid containing Y(III) oleate and Ce(III) oleate complexes was heat treated at 400°C. The powder after planetary ball milling contains monodisperse near spherical particles of 0·2 μm. These particles contain monodisperse nanocrystallites of size <10 nm. The yttria doped ceria powder pellets were sintered to >98% theoretical density at 1450°C. The sintered ceramic showed an ionic conductivity of 0·0623 S cm⁻¹ at 800°C and activation energy of 1·0 eV.