Abstract: A catalyst is comprised of a catalyst carrier and a coat layer containing cerium particles, active alumina particles and a catalyst component of a noble metal; and barium barium oxide is immobilized on the cerium oxide particles. The catalyst can suppress the growth of crystals of cerium oxide due to the immobilization of the barium oxide thereon, thereby improving heat resistance of the catalyst.

Abstract: A catalyst for the purification of exhaust gases contains a catalyst carrier with a first coat layer formed on a surface of the catalyst carrier and with a second coat layer formed on a surface of the first coat layer. The first coat layer contains an active alumina and a catalyst component comprised of a noble metal such as platinum and rhodium and at least one of zirconium oxide, lanthanum oxide and barium oxide is immobilized on particles of the active alumina, and the second coat layer contains an active alumina, cerium oxide and a catalyst component comprised of another noble metal such as palladium. The oxides of zirconium, lanthanum and/or barium can prevent the alumina particles from aggregating together due to heat, thereby improving heat resistance of the catalyst.

Abstract: A catalyst for purifying exhaust gas, comprising a catalyst carrier, a first coating layer formed on a surface of the catalyst carrier and mainly consisting of active alumina oxide containing platinum and rhodium and a second coating layer formed on a surface of the first coating layer and mainly consisting of palladium and composite powder including zirconium oxide and lanthanum oxide fixed on a surface of cerium oxide, and a method of manufacturing the catalyst.