Powder Technology, Vol.253, 304-310, 2014
Effect of rare earth dopants on structural characteristics of nanoceria synthesized by combustion method
Rare earth (RE)-doped ceria powders with a chemical composition of Ce1-xRExO2-x/2 (X: 0.1 and RE: Gd, Sm, Er, Pr, Nd and Y) were prepared by nitrate-fuel combustion method. The TG and DT analyses of the as-synthesized powders showed a complete combustion with a small range endothermic process within a broad exothermic reaction. GDC, SDC, EDC, PDC, NDC and YDC precursors were calcined at 700 degrees C for 2 h and characterized using XRD, SEM and TEM. Powder characteristics such as morphology, crystallite size, primary particle size, lattice parameter and lattice strain of calcined powders have been studied. All X-ray diffraction patterns of as-synthesized and calcined samples were indexed as fluorite structure. The crystallite size of nanoceria obtained by Scherrer's formula was between 17 and 19.5 nm and via Williamson-Hall (W-H) plots in the range of 25-38 nm that shows the effect of lattice strain on the average crystallite size. Primary particle size calculated from BET data was in the range of 24-37 nm. TEM images showed fine spherical particles and SAED patterns confirmed fluorite structure of all powders. (C) 2013 Elsevier B.V. All rights reserved.