Temperature-programmed reduction of lightly yttrium-doped Au/CeO2 catalysts Correlation between oxygen mobility and WGS activity

摘要

The reducibility of Au catalysts on CeO2 supports doped with 1 and 2.5 mass% Y2O3 by two types of preparation methods (impregnation and co-precipitation) has been studied by temperature-programmed reduction and compared with that of pure Au/CeO2. The kinetic parameters of reduction were determined simulating each reduction process. The capacities of these catalysts to retain oxygen have been evaluated by temperature-programmed desorption. The catalytic activities in water gas shift reaction were determined measuring CO conversion between 413 and 623 K. The catalytic performances of all these catalysts were explained in terms of mobility of the oxygen ions of the CeO2 lattice.