Ceria nanoparticles with 20 and 40at.% RE (RE = Y, Sm, Gd or Yb) dopants were

synthesized through a micro-emulsion method. Independently of the dopant nature

and concentration, nearly monodispersed nanoparticles (3 to 5nm) were observed

via high-resolution transmission electron microscopic analysis. The ceria lattice either expands or contracts depending on the dopant cation ionic radii, as indicated

by X-ray diffraction studies. X-ray photoelectron and Raman spectroscopic studies

were used to quantify the cerium oxidation state and oxygen vacancy

concentration. The results showed the tunability of the oxygen vacancy and Ce3+

concentrations based on the dopant properties. First principles simulations using

the free energy density functional theory method support the observed

experimental trends. The reported results establish a relationship between the

oxygen vacancies and oxidation states in doped ceria required for tailoring

properties in catalytic and biomedical applications.

Dopant-Mediated Oxygen Vacancy Tuning in Ceria Nanoparticles. S.Babu,

R.Thanneeru, T.Inerbaev, R.Day, A.E.Masunov, A.Schulte, S.Seal:

Nanotechnology, 2009, 20[8], 085713