Nanocrystalline Ce1–xRExO2–y powders with a controlled size of 3 to 5nm were synthesized by using micro-emulsion techniques. The nanoceria retained its cubic fluorite structure over the complete doping range. X-ray diffraction and Raman spectroscopic studies showed that the lattice distortion increased with the amount of doping, and was higher for La-doped samples as compared with Nd-doped ones. A spatial correlation model, used for Raman analysis, suggested that there was an increased defect concentration in the doped samples, as compared to nanoceria.

Role of Trivalent La and Nd Dopants in Lattice Distortion and Oxygen Vacancy Generation in Cerium Oxide Nanoparticles. S.Patil, S.Seal, Y.Guo, A.Schulte, J.Norwood: Applied Physics Letters, 2006, 88[24], 243110 (3pp)