Synthesis and structural, optical and thermal properties of ceria and rare earth doped ceria nanocrystals

Single crystalline ceria and rare earth doped ceria nanoparticles have been successfully synthesized by sonochemical method using water solvent from aqueous solution containing Ce(NO3)(3)center dot 6H(2)O, Gd(NO3)(3)center dot 6H(2)O, Sm(NO3)(3)center dot 6H(2)O, NaOH and hexamethylenetetramine (HMTA) as a surfactant. Prepared CeO2, Gd:CeO2 and Sm:CeO2 nanoparticles were dried in air oven at 100 degrees C for 24 h. The synthesized samples have been subjected to various characterization studies such as X-ray powder diffraction (XRD) for structural confirmation of fluorite cubic. The morphology of the prepared materials was studied by field emission scanning electron microscopy (FE-SEM). Thermo-gravimetric analysis (TG/DTA) reveals that ceria and doped ceria are thermal stable upto 400 degrees C. UV-vis absorption of Gd:CeO2 shows red shift, due to the electron- phonon interaction. Fluorescence studies show the emission peaks for ceria at 425 nm and gadolinium and samarium doped ceria at 466 nm.