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The redox properties of dense pellets of Ce0.50Zr0.50O2 have been investigated by temperature programmed reduction (TPR) (1023-1373K) and mild temperature oxidation (873K) cycles, X-ray powder diffraction technique (XRD), RAMAN spectroscopy and electrochemical impedance spectroscopy (EIS) have been used to characterize structural and conductivity modifications. The redox treatments promote both the reducibility at lower temperature and the electrical conductivity of this material. A gradual transition from a tetragonal to a pyrochlore cubic phase with the progress of reduction has been observed, while the nature of the phase after reoxidation depends on the temperature of reduction. The promotion of conductivity is correlated with the partial reordering of cationic lattice, but not specifically with the formation of the k-phase.

Ce0.8Zr0.2O2and Ce0.8La0.5Nd0.2Zr0.13O2-x, were prepared with a surfactant assisted approach and impregnated with different amounts of nickel. The catalysts were studied in the dry reforming reaction with the aim of using them in a biogas fuelled IT-SOFC anode. The oxidative dry reforming reaction was also investigated, finding that small amounts of oxygen in the biogas mixture reduce the effect of dry reforming side reactions. Catalysts containing Lanthanum and Neodymium showed an improved activity at 600 °C and 650 °C in terms of H2selectivity and carbon resistance.

The redox properties of dense pellets of Ce0.50Zr0.50O2have been investigated by temperature programmed reduction (TPR) (1023-1373K) and mild temperature oxidation (873K) cycles, X-ray powder diffraction technique (XRD), RAMAN spectroscopy and electrochemical impedance spectroscopy (EIS) have been used to characterize structural and conductivity modifications. The redox treatments promote both the reducibility at lower temperature and the electrical conductivity of this material. A gradual transition from a tetragonal to a pyrochlore cubic phase with the progress of reduction has been observed, while the nature of the phase after reoxidation depends on the temperature of reduction. The promotion of conductivity is correlated with the partial reordering of cationic lattice, but not specifically with the formation of the κ-phase.