| abstract |
(57) [Problem] To improve the durability of OSC by using a composite oxide carrier and to suppress the peeling of a coat layer and the decrease in specific surface area during a durability test. The composite oxide comprises a mixture of a composite oxide prepared by a coprecipitation method from a plurality of types of salt solutions containing Al, Ce and Zr, and a heat-resistant inorganic oxide. In a weight ratio of composite oxide: heat-resistant inorganic oxide = 5: 3 To 2: 3. By mixing the heat-resistant inorganic oxide, the adhesion to the honeycomb substrate is improved, and peeling of the coat layer during the durability test can be suppressed. |