Three-way catalyst having an upstream multi-layer catalyst

摘要

Disclosed herein is a layered, three-way conversion catalyst having the capability of simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides being separated in a front and rear portion is disclosed. Provided is a catalytic material of at least two front and two rear layers in conjunction with a substrate, where each of the layers includes a support, all layers comprise a platinum group metal component, and the rear bottom layer is substantially free of a ceria-containing oxygen storage component (OSC).