An XPS study of the oxidation of reduced ceria-lanthana nanocrystals
Fleming, Peter G.
Holmes, Justin D.
Morris, Michael A.
Detailed X-ray photoelectron spectroscopy (XPS) studies on the oxidation of an extensively cleaned, reduced ceria–lanthana solid solution (12.5 mol% La to Ce) was performed. Uptake of oxygen during oxidation followed a logarithmic dependence on exposure. Differential charging during oxidation suggests that the oxidation process is diffusion limited. No evidence for surface 3+ cerium states in the fully oxidised samples, which are anion defect free within the limits of experimental accuracy, was found. The data suggest that there is no evidence for the inherent stability of anion vacancies (associated with Ce3+ sites) at the surface of these nanocrystals.
Oxidation , Cerium , Cerium compounds , Lanthanum oxides , Nanocrystals , Photoelectron spectroscopy , X ray photoelectron spectroscopy , Anion vacancy , Defect-free , Differential charging , Diffusion limited , Logarithmic dependence , Oxidation process , X-ray photoelectron spectroscopy studies , XPS
Fleming, P., Ramirez, S., Holmes, J. D. and Morris, M. A. (2011) 'An XPS study of the oxidation of reduced ceria–lanthana nanocrystals', Chemical Physics Letters, 509(1), pp. 51-57. doi: 10.1016/j.cplett.2011.04.090