three-way conversion catalyst composition, catalyst article, exhaust gas treatment system, method of manufacturing the three-way conversion catalyst composition and method for treating an exhaust gas

摘要

the present invention relates to catalyst compositions effective to perform three-way conversion including platinum group metal nanoparticles (e.g., pt, pd, au, ru, rh, alloy nanoparticles and mixtures thereof), the nanoparticles of which an average particle size of about 15 to about 50 nm, and where the nanoparticles are dispersed in a refractory metal oxide component. in some of these catalyst compositions, a significant portion, for example, at least 90% of the nanoparticles, has a particle size within this range. methods of preparing and using such catalyst compositions are also provided, as well as catalyst articles and emission treatment systems comprising such catalyst compositions.