Catalysts for lean burn

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The present invention relates to catalysts for lean burn and provides a catalyst for lean burn that is capable of purifying NO x sufficiently and that has a high ability to purify CO and HC over a wide temperature range from low to high temperatures. The present invention provides a catalyst for a lean-burn engine to purify exhaust gas, the catalyst including : an integrally structured support; and a catalyst layer containing a precious metal element, provided on the integrally structured support and having at least two layers that include an upper layer and a lower layer; wherein the upper layer of the catalyst layer contains at least a proton-substituted ²-type zeolite and a ceria-based oxide supporting rhodium, and the lower layer of the catalyst layer contains at least a NO x storage component and platinum supported on an inorganic oxide.