We implement DFT calculations by a Hubbard-like correction for localized strongly correlated electrons, coupled with a generalized gradient approximation to the exchange-correlation functional to elucidate the role of the ceria based catalytically active supports for the chemical reactions involving reduction-oxidation processes. These catalytic processes are relevant for many industrial applications, such as catalytic converters in automotive applications, solid oxide fuel cells, and hydrogen production from biomass. The Hubbard-like correction U is computed from first principles as physical property of the system. We find that the high performance of ceria-based oxides as an active support for noble metals in catalysis relies on an efficient supply of lattice oxygen at reaction sites governed by oxygen vacancy formation.