Activity Descriptor for Catalytic Reactions on Doped Cerium Oxide

It is well-known that ceria enhances chemical activity and catalyst durability in several important catalytic reactions, including CO oxidation and NO_<i>x</i> reduction. Of great practical value is then having a theoretical model to predict the effect of doping on the ceria activity before the actual synthesis of its compounds. Such a model is developed in the present work on the basis of experimentally observed data, where we verify our hypothesis that the energy for oxygen vacancy formation is a simple yet powerful activity descriptor for this class of materials. We further benchmark and use our DFT + <i>U</i> computations to estimate this descriptor and to suggest a few transition metals that would increase the activity of ceria toward redox reactions. This new activity descriptor might be an important factor in similar systems because it does not require any knowledge about the exact chemistry or mechanism of catalysis