Exhaust gas purification device for internal combustion engine

1. An exhaust gas purification device for an internal combustion engine, provided in an exhaust passage of the internal combustion engine, comprising:

a filter-shape carrier adapted to trap particulate matter in exhaust gas; and

an oxidation catalyst supported on the filter-shape carrier and comprising:

a particulate oxygen storage material; and

an oxygen ion conductive material supported around the oxygen storage material in surface contact therewith,

wherein the oxygen ion conductive material has a film form covering a periphery of the oxygen storage material, and

wherein a crack reaching the oxygen storage material in the oxygen ion conductive material is formed on the oxygen ion conductive material.

2. The exhaust gas purification device according to claim 1 , wherein

an outer diameter of the oxygen storage material is 5 μm or less, and

a thickness or an outer diameter of the oxygen ion conductive material is 30% or less of the outer diameter of the oxygen storage material.

3. The exhaust gas purification device according to claim 1 , wherein an outer diameter of the oxygen storage material is a value represented by the following calculation expression:

Outer Diameter of Oxygen Storage Material=Particle Volume V (cm 3 /g)÷Particle Surface Area S (cm 2 /g)×6.

4. The exhaust gas purification device according to claim 1 , wherein a volume of the oxygen ion conductive material is 3 times or less a volume of the oxygen storage material.

5. The exhaust gas purification device according to claim 1 , wherein the oxygen ion conductive material is a perovskite type oxide.