US Patent 7754171 Multilayered catalyst compositions

A multilayered, three-way conversion catalyst having the capability of simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides is disclosed. Provided is a catalytic material of at least four layers in conjunction with a carrier, where each of the layers includes a support, at least three layers comprise a precious metal component, and at least one layer comprises an oxygen storage component (OSC). The catalytic material can further comprise a fifth layer, where at least four layers comprise a precious metal component, at least one layer comprises an oxygen storage component, and at least one layer is substantially free of an oxygen storage component.