Oxygen mobility of Pt-promoted doped CeO2–ZrO2 solid solutions: Characterization and effect on catalytic performance in syngas generation by fuels oxidation/reforming

For nanocrystalline ceria–zirconia samples doped with rare-earth (Gd, Pr, La) cations prepared via modified Pechini route and promoted by Pt supported by wet impregnation, parameters characterizing their oxygen mobility and reactivity were estimated from results of oxygen isotope exchange experiments in both isothermal and temperature-programmed modes using different procedures. Observed trends in variation of oxygen exchange parameters with the type and content of a dopant were explained with a due regard for the real structure and surface properties of samples earlier characterized in detail. For the reaction of partial oxidation and dry reforming of methane in diluted feeds, catalytic activity correlates both with Pt dispersion and oxygen mobility. For the reactions of acetone autothermal reforming and CH4 dry reforming in realistic feeds, catalytic activity is mainly determined by the surface/bulk oxygen mobility responsible for coking suppression.