Synthesis of nanocrystalline CeO₂–Y₂O₃ powders by a nitrate–glycine gel-combustion process

In this work, the synthesis of CeO₂–10 mol% Y₂O₃ powders by a nitrate–glycine gel-combustion route was investigated. Special attention was given to the influence of the glycine/metal ratio and calcination temperature on powder morphology. In contrast to the usual reported behavior, the best powder properties (crystallite size, 4.5–7 nm; specific surface area; 25–40 m²/g) were obtained for slow combustion processes with glycine/metal ratios of 1.5–2, whereas energetic reactions resulted in large crystallite and particle sizes. Furthermore, it was found that the crystallite size increases considerably even at moderate calcination temperatures (350–550 °C), showing the high reactivity of these nanopowders.