Exhaust gas purifying catalyst and method for producing same
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsIwao Nitta, Naotaka Sawada
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Abstract
Provided is a non-noble metal-based exhaust gas purifying catalyst which is capable of removing an unreacted material such as carbon monoxide in an exhaust gas at low temperatures. An exhaust gas purifying catalyst of the present invention contains a ceria-based carrier and a complex oxide of cobalt and an additional metal element, said complex oxide being supported by the ceria carrier. The additional metal element contains a metal element that is selected from the group consisting of copper, silver, magnesium, nickel, zinc and combinations of these elements.
Claims16
An exhaust gas purifying catalyst, comprising
- a ceria-based support, and
- a composite oxide of cobalt Co and an additive metal element M, supported on said ceria-based support,
- wherein said additive metal element comprises copper,
- wherein said composite oxide has a spinel structure, and
- wherein, when said composite oxide is analyzed by Rietveld analysis, compared with cobalt oxide not containing said additive metal element, the MTET-O bond distance in the spinel structure of said composite oxide is extended by 0.03 Å or more, and/or the MOCT-O bond distance in the spinel structure of said composite oxide is contracted by 0.03 Å or more.
Dependencies are inferred from the claim text.