Modification of Cu/ZSM-5 catalyst with CeO2 for selective catalytic reduction of NOx with ammonia

The interactions of ceria with the metal and support lead copper species mainly in the form of surface CuO clusters. It facilitates the fast NH3-SCR at low temperatures via enhanced NO2 production from NO oxidation, but makes against the high-temperature reaction due to the reduced supply of the reductant via catalyzing NH3 oxidation. The inhibition is also attributed to the decreases in the amounts of isolated Cu2+ and acid sites