Patent ID: 7723259

Claim:
A particulate matter oxidizing catalyst comprising: gallium; at least one metal selected from the group consisting of: manganese, iron, cobalt, nickel, copper, yttrium, zirconium, niobium, molybdenum, silver, lanthanum, praseodymium, neodymium and gold; and cerium, wherein a first oxide includes: cerium, and a first metal which is at least one element selected from the group consisting of: gallium, manganese, iron, cobalt and nickel, wherein a second oxide includes: cerium, and a second metal consisting of praseodymium, and wherein the second oxide and the first oxide have a content ratio of second oxide/(first oxide+second oxide)=0.1 by mass to 0.8 by mass and wherein cerium and praseodymium which are included in the second oxide have a mole ratio of cerium:praseodymium=4:1 to 1:4.