An integrated multi-functional catalyst system includes a diesel particulate filter having an inlet side for receiving flow and an opposite outlet side, a substrate in the diesel particulate filter having an interior wall surface and an exterior wall surface, a first washcoat layer applied to the interior wall surface and adjacent the inlet side, and a second washcoat layer applied to the exterior wall surface and adjacent the outlet side, wherein flow distribution through the substrate is dispersed for minimizing back pressure. The diesel particulate filter may be one of a plurality of honeycomb cells.