Abstract:
Ceria-samaria and ceria-zirconia mixed oxides have been prepared by a modified coprecipitation method (CP-H2O2) adding H2O2 to the water solution of the corresponding nitrates in order to obtain a material with improved catalytic properties versus the oxidation of light hydrocarbons. In fact, adding H2O2 during the coprecipitation of the oxides is an effective way to improve the reducibility at low temperature, the oxygen storage capacity (OSC) and the thermal resistance of these mixed oxide compositions. Several parameters of the synthesis such as the amount of H2O2 , pH, temperature and aging of the precipitate has been investigated and correlated with the structural and morphological characteristics of the oxides obtained. The materials have been also characterized in terms of its sintering capability and conductivity. Moreover the characteristics of the ceria-samaria oxides so prepared have been compared with those ones synthesized by other approaches and with one purchased. Ceria- samaria prepared by CP-H2O2 shown a higher surface area (SA) and OSC while the conductivity could be improved by an appropriate processing of powders. The aim of the work was to realize a material with enhanced catalytic properties, to be used as catalytic promoter in the intermediate temperature solid oxide fuel cell (ITSOFC) anode and cathode.
