The present disclosure provides catalyst compositions for NO.sub.x conversion and wall-flow filter substrates comprising such catalyst compositions. Certain catalyst compositions include a zeolite with sufficient Cu exchanged into cation sites thereof to give a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component (e.g., alumina) including a plurality of particles having a D.sub.90 particle size of about 0.5 to 20 microns in a concentration of about 1 to 20 wt. %. The zeolite and copper trapping component can be in the same washcoat layer or can be in different washcoat layers (such that the copper trapping component serves as a “pre-coating” on the wall-flow filter substrate).

The present disclosure provides catalyst compositions for NO.sub.x conversion and wall-flow filter substrates comprising such catalyst compositions. Certain catalyst compositions include a zeolite with sufficient Cu exchanged into cation sites thereof to give a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component (e.g., alumina) including a plurality of particles having a D.sub.90 particle size of about 0.5 to 20 microns in a concentration of about 1 to 20 wt. %. The zeolite and copper trapping component can be in the same washcoat layer or can be in different washcoat layers (such that the copper trapping component serves as a pre-coating on the wall-flow filter substrate).