EXHAUST GAS PURIFICATION CATALYST, EXHAUST GAS PURIFICATION MONOLITH CATALYST, AND METHOD FOR PRODUCING EXHAUST GAS PURIFICATION CATALYST

摘要

An exhaust gas purification catalyst contains a first catalyst in which an oxide of general formula (1): La,M 1-x M'O 3-´ (where La is lanthanum, M is at least one selected from a group consisting of barium (Ba), strontium (Sr) and calcium (Ca), M' is at least one selected from a group consisting of iron (Fe), cobalt (Co), nickel (Ni) and manganese (Mn), ´ is the amount of oxygen defect, and x and ´ satisfy 0 < x ‰¤ 1 and 0 ‰¤ ´ ‰¤ 1) is supported by an oxide capable of occluding and releasing oxygen, and a second catalyst containing a noble metal. The particle size of the oxide capable of occluding and releasing oxygen is within the range from 1 to 50 nm. The particle size of the oxide of the general formula (1) is within the range from 1 to 30 nm.