AVS 47th International Symposium
    Surface Science Monday Sessions
       Session SS1-MoA

Paper SS1-MoA8
Reducibility of Model Catalytic Converter Oxygen Storage Materials: Thin Ce@sub x@Zr@sub 2-x@O@sub 2@(111) Films Grown on Y-Stabilized Zirconia Single Crystals

Monday, October 2, 2000, 4:20 pm, Room 208

Session: Model Catalysts at High Pressures
Presenter: C.H.F. Peden, Pacific Northwest National Laboratory
Authors: C.H.F. Peden, Pacific Northwest National Laboratory
T. He, Pacific Northwest National Laboratory
G.S. Herman, Pacific Northwest National Laboratory
Y.-J. Kim, Taejon National University of Technology
Y. Gao, Pacific Northwest National Laboratory
S. Thevuthasan, Pacific Northwest National Laboratory
Correspondent: Click to Email
Dramatic improvements have been made in automobile exhaust converter catalysts by the incorporation of oxygen storage (OS) materials, usually consisting of ceria (CeO@sub 2@) or modified ceria, that can effectively damp deviation in the exhaust air/fuel (A/F) ratio bringing the gas phase closer to the stoichiometric point. We have been growing and characterizing thin films of CeO@sub 2@ and ceria-zirconia (Ce@sub x@Zr@sub 2-x@O@sub 2@) for use as model materials for fundamental studies of their oxygen uptake, storage, and release properties. In this presentation, the growth and characterization (by x-ray diffraction, atomic force microscopy, reflection high-energy electron diffraction, low-energy electron diffraction, x-ray photoelectron spectroscopy (XPS) and diffraction, and low-energy ion scattering spectroscopy) of model CeO@sub 2@ and Ce@sub x@Zr@sub 2-x@O@sub 2@ thin films will be presented. A wide range of growth parameters using oxygen plasma-assisted molecular beam epitaxy have been used, and successful production of pure-phase, single-crystalline epitaxial oxide films has been achieved. We will also report results of XPS and temperature-programmed desorption experiments that have probed the rates of oxygen incorporation and removal from these materials. In particular, we have found that doping of the CeO@sub 2@ by Zr markedly enhances the kinetics of these processes.@footnote 1@ @FootnoteText@ @footnote 1@Pacific Northwest National Laboratory is a multiprogram national laboratory operated for the U.S. Department of Energy by Battelle Memorial Institute under contract number DE-AC06-76RLO 1830.