Nanostructured Oxide-Based Powders:Investigation of the Growth Mode of the CeO_2 Clusters on the YSZ Surface

摘要

CeO_2/YSZ nanocomposite powders,characterized by increasing Ce/Zr atomic ratio,were obtained by depositing,by wet impregnation,different amounts of CeO_2 on the yttria-stabilized zirconia(YSZ)surface.These powders were characterized by means of X-ray photoelectron spectroscopy,transmission electron microscopy,energy dispersive spectroscopy,and X-ray diffraction.Experimental results allow us to obtain interesting information concerning the growth mode,the morphology,and the dimensions of the CeO_2 clusters on the YSZ supporting surface.A 3-D growing mechanism was observed for the CeO_2 nanoparticles.With increasing Ce/Zr atomic ratio the CeO_2 clusters become more and more spherical.Moreover,XPS data also show the presence of Ce(III)and Ce(IV)ions at the interface supported/supporting oxides.