Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

PP-IV-725 mm diameter and 2 mm thickness [2]. The Ag paste was applied as cathode metal onto aside of the disc then a mixture of Au paste and catalyst powders were applied as anodecatalystwith onto the other side of the YSZ disc. The reactor was placed in an electric furnaceto control the temperature. Catalytic properties were tested in direct oxidation of propane inmembrane reactor between 200 and 600 °C.Results and DiscussionThe XRD patterns of all the calcined samples correspond to the fluorite phase of theoxidic systems. Small-angle X-ray diffraction patterns and nitrogen adsorption-desorptionisotherms indicate a mesoporous structure of the calcinated powders. The surfacestoichiometries reveal a good agreement with the nominal ones from the sample’s bulk. Allthe results show that the improvement of morphology, microstructure and composition of thematerials for the SOFC components play an important role for achieving a high cellperformance. The value of determined resistivity decreases with increasing content of TiO 2and CeO 2 . The analysis of EI spectra suggests that the higher electrochemical activity may bedue to an extension of the reaction zone into the porous zone of mixed conduction caused bythe introduction of TiO 2 and CeO 2 , leading to the decrease in the specific resistivity. Thehighest C 3 H 8 conversion was obtained, at 600 °C, over Ni/CeO 2 -ZrO 2 –Y 2 O 3 catalyst followedby Ni/TiO 2 -ZrO 2 –Y 2 O 3 . Decreasing in Ni loading in the catalysts resulted in a substantialdecrease in the activity.ConclusionsAll the results show that the improvement of morphology, microstructure andcomposition of the materials for the SOFC components play an important role for achieving acell performance.AcknowledgementsThe financial support by the Romanian Ministry of Education and Research - CEEX-AMCSIT 267 is highly appreciated.References1. C. Lu, S. An, W.L. Worrell, J.M. Vohs and R.J. Gorte, Solid State Ionics, 175 (2004) 47.2. K. Takehira, J. Shimomura, S. Hamakawa, T. Shishido, T. Kawabata, K. Takaki, Appl. Catal. B:Environmental, 55 (2005) 93.3. Y. Ye, L. Rihko-Struckmann, B. Munder, K. Sundmacher, Appl. Catal. A: General 285 (2005) 86.409