The size and strain effects on the Raman spectra of Ce1-xNdxO2-δ (0≤x≤0.25) nanopowders

Ultrafine Ce1-xNdxO2-delta (x = 0-0.25) powders were synthesized by self-propagating room temperature synthesis. Raman spectra were measured at room temperature in the 300-700 cm(-1) spectral range. The shift and asymmetric broadening of the Raman F-2g mode at about 454 cm(-1) in pure and doped ceria samples could be explained with combined size and inhomogenous strain effects. Increased concentration of O2- vacancies with doping is followed by an appearance of new Raman feature at about 545 cm(-1). (c) 2005 Elsevier Ltd. All rights reserved.