A catalyst for purifying exhaust gas

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PROBLEM TO BE SOLVED : To suppress the sulfur poisoning of an NOx occluding material and to improve NOx purifying efficiency by forming a coated layer consisting of a porous oxide carrier carrying the NOx occluding material and a noble metal on the surface of a honeycomb shaped carrier base material and also forming another coated layer consisting of Rh/ZrO2. SOLUTION : The coated layer 2 consisting of the porous oxide carrier carrying respectively the NOx occluding material consisting of at least one kind selected among an alkali metal, an alkaline earth metal and a rare earth element and the noble metal is formed on the whole surface of a monolithic base material 1 formed in a form of the honeycomb. Then, another coated layer 3 consisting of Rh/ZrO2 carrying the rhodium on the zirconia is formed on the surface of the coated layer 2 within a prescribed range (for example 3.2% of total length) from an influent gas side end surface 10 of the monolithic base material 1. At this time, the coated layer 2 is formed mainly, for example, with Al2O3 powder and TiO2 powder and carries CeO2-ZrO2 composite oxide powder, Pt, Ba, K and Li.