US Patent 8007750 Multilayered catalyst compositions

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 is disclosed. Methods of making and using the same are also provided. In one or more embodiments, the catalyst comprises three layers of catalytic material in conjunction with a carrier. A first layer comprises a platinum component on a first support; a second layer comprises a rhodium component on a second support; and a third layer comprises a palladium component and a third support. The palladium, rhodium, and/or platinum can independently be deposited on a support of high surface area refractory metal oxide, or of an oxygen storage component, or both.