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Provided are catalyst composites whose catalytic material is effective to substantially simultaneously oxidize carbon monoxide and hydrocarbons and reduce nitrogen oxides. The catalyst composites have a two-metal layer on a carrier, the two-metal layer comprising a rhodium component supported by a f

Provided are catalyst composites whose catalytic material is effective to substantially simultaneously oxidize carbon monoxide and hydrocarbons and reduce nitrogen oxides. The catalyst composites have a two-metal layer on a carrier, the two-metal layer comprising a rhodium component supported by a first support comprising a refractory metal oxide component or a first ceria-zirconia composite; a palladium component supported by a second support comprising a second ceria-zirconia composite; one or more of a promoter, stabilizer, or binder; wherein the amount of the total of the first and second ceria-zirconia composites in the two-metal layer is equal to or greater than the amount of the refractory metal oxide component. Methods of making and using the same are also provided.

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1. An automotive catalyst composite comprising: a catalytic material on a carrier, the catalytic material comprising a two-metal layer that comprises:a rhodium component supported by a first support comprising a refractory metal oxide component and optionally further a first ceria-zirconia composite

1. An automotive catalyst composite comprising: a catalytic material on a carrier, the catalytic material comprising a two-metal layer that comprises:a rhodium component supported by a first support comprising a refractory metal oxide component and optionally further a first ceria-zirconia composite;a palladium component supported by a second support comprising a second ceria-zirconia composite;one or more of a promoter, stabilizer, or binder;wherein the catalytic material is effective for three-way conversion (TWC) to substantially simultaneously oxidize carbon monoxide and hydrocarbons and reduce nitrogen oxides, andwherein the amount of the total of the first ceria-zirconia composite, if present, and the second ceria-zirconia composite in the two-metal layer is equal to or greater than the amount of the refractory metal oxide component. 2. The composite of claim 1, wherein the palladium component, the rhodium component, or both are thermally-fixed. 3. The composite of claim 1, wherein the first support for the rhodium component comprises an alumina-based support or a zirconium-based support. 4. The composite of claim 3, wherein the first support for the rhodium component comprises an activated alumina compound selected from the group consisting of alumina, alumina-zirconia, alumina-ceria-zirconia, lanthana-alumina, lanthana-zirconia-alumina, baria-alumina, baria lanthana-alumina, baria lanthana-neodymia alumina, and alumina-ceria. 5. The composite of claim 1, wherein the first support for the rhodium component further comprises a ceria-zirconia composite comprising 20% or less by weight of ceria. 6. The composite of claim 1, wherein the second support for the palladium component comprises a ceria-zirconia composite comprising at least 25% by weight of ceria. 7. The composite of claim 1, wherein a weight ratio of the amount of the total of the first and second ceria-zirconia composites to the amount of the refractory metal oxide component in the two-metal layer is greater than 1:1. 8. The composite of claim 7, wherein the weight ratio is 2.5:1 or greater. 9. The composite of claim 8, wherein the weight ratio is 4:1 or greater. 10. The composite of claim 1 further comprising a palladium component on a refractory metal oxide component. 11. The composite of claim 1, wherein the two-metal layer comprises, by weight percent of the two-metal layer: the second ceria-zirconia composite in an amount in the range of 40-50%;the refractory metal oxide component in an amount in the range of 40-50%; andone or more of lanthana, baria, zirconia, and strontium in an amount of up to 10%;wherein the second ceria-zirconia composite comprises ceria in an amount in the range of 25-45% by weight of the second ceria-zirconia composite. 12. The composite of claim 1, wherein the two-metal layer comprises, by weight percent of the two-metal layer: the second ceria-zirconia composite in an amount in the range of 70-80%;the refractory metal oxide component in an amount in the range of 10-20%; andone or more of lanthana, baria, zirconia, and strontium in an amount of up to 10%;wherein the second ceria-zirconia composite comprises ceria in an amount in the range of 25-45% by weight of the second ceria-zirconia composite. 13. The composite of claim 12, wherein the refractory metal oxide component comprises an alumina-ceria compound. 14. The composite of claim 12 further comprising a second layer over the two-metal layer, the second layer comprising: a rhodium component on an activated alumina component selected from the group consisting of alumina, alumina-zirconia, alumina-ceria-zirconia, lanthana-alumina, lanthana-zirconia-alumina, baria-alumina, baria lanthana-alumina, baria lanthana-neodymia alumina, and alumina-ceria; anda palladium component on a third ceria-zirconia composite comprising ceria in an amount in the range of 5-20% by weight of the third ceria-zirconia composite. 15. The composite of claim 1, wherein the catalytic material further comprises a second layer over the two-metal layer, the second layer comprising a rhodium component on a third support, a platinum component on a fourth support, a palladium component on a fifth support, or combinations thereof. 16. The composite of claim 15, wherein the second layer comprises the rhodium component on the third support that comprises an activated alumina compound selected from the group consisting of alumina, alumina-zirconia, alumina-ceria-zirconia, lanthana-alumina, lanthana-zirconia-alumina, baria-alumina, baria lanthana-alumina, baria lanthana-neodymia alumina, and alumina-ceria. 17. The composite of claim 16, wherein the second layer comprises the palladium component on the fifth support that comprises a third ceria-zirconia composite. 18. The composite of claim 1, wherein the catalytic material comprises a single layer. 19. The composite of claim 1, wherein the catalytic material comprises two layers. 20. An exhaust gas treatment system comprising the catalyst composite of claim 1 located downstream of a gasoline engine. 21. The exhaust gas treatment system of claim 20, further comprising a close-coupled three-way conversion (TWC) catalyst composite downstream of the gasoline engine, wherein the catalyst composite is located downstream of the close-coupled TWC catalyst composite and upstream of a NOx abatement catalyst. 22. A method for treating an exhaust gas comprising hydrocarbons, carbon monoxide, and nitrogen oxides comprising: contacting the exhaust gas with the catalyst composite of claim 1. 23. An automotive catalyst composite comprising: a catalytic material on a carrier, the catalytic material comprising a two-metal layer that comprises:a rhodium component supported by an activated alumina compound selected from the group consisting of alumina, alumina-zirconia, alumina-ceria-zirconia, lanthana-alumina, lanthana-zirconia-alumina, baria-alumina, baria lanthana-alumina, baria lanthana-neodymia alumina, and alumina-ceria;a palladium component thermally-fixed to a ceria-zirconia composite that comprises ceria in an amount in the range of 25-45% by weight of the ceria-zirconia composite;one or more of lanthana, baria, and zirconia;wherein the catalytic material is effective for three-way conversion (TWC) to substantially simultaneously oxidize carbon monoxide and hydrocarbons and reduce nitrogen oxides, andwherein a weight ratio of the amount of the ceria-zirconia composite to the amount of the activated alumina compound in the two-metal layer is 4:1 or greater. 24. The composite of claim 23, wherein the activated alumina compound comprises an alumina-ceria compound. 25. The composite of claim 23 further comprising a second layer over the two-metal layer, the second layer comprising: a rhodium component supported by an activated alumina compound; and a ceria zirconia composite. 26. The composite of claim 25, wherein a palladium component is provided on a ceria-zirconia composite that comprises ceria in an amount in the range of 5-20% by weight of the ceria-zirconia composite;wherein the amount of the rhodium component in the second layer is approximately the same as the amount of the rhodium component in the two-metal layer. 27. A method of making a catalyst composite comprising: forming a three-way conversion (TWC) catalytic material by: dispersing a rhodium component onto a first support comprising a refractory metal oxide component or a first ceria-zirconia composite to form a first impregnated support;optionally, fixing the rhodium component to the first impregnated support;dispersing a palladium component onto a second support comprising a second ceria-zirconia composite to form a second impregnated support;optionally, fixing the palladium component to the second impregnated support;thereafter forming an aqueous washcoat dispersion by mixing water, the first and second impregnated supports, and one or more of a promoter, stabilizer, or binder;coating the aqueous washcoat dispersion onto a carrier to form a two-metal single layer on the carrier;calcining the two-metal layer to form the catalyst composite;wherein the catalytic material is effective for three-way conversion (TWC) to substantially simultaneously oxidize carbon monoxide and hydrocarbons and reduce nitrogen oxides, andwherein the amount of the total of the first and second ceria-zirconia composites is equal to or greater than the amount of the refractory metal oxide component in the two-metal layer. 28. The method of claim 27, wherein the palladium component, the rhodium component, or both are thermally-fixed. 29. The method of claim 27 further comprising well-dispersing the rhodium component onto the first support and well-dispersing the palladium component onto the second support. 30. The method of claim 27 further comprising coating a second layer onto the two-metal layer, the second layer comprising a rhodium component on a third support comprising an activated alumina compound selected from the group consisting of alumina, alumina-zirconia, alumina-ceria-zirconia, lanthana-alumina, lanthana-zirconia-alumina, baria-alumina, baria lanthana-alumina, baria lanthana-neodymia alumina, and alumina-ceria and optionally a platinum component on a fourth support, a palladium component on a fifth support, or both.