Improvement of the Oxygen-Storage Capacity of an Intelligent Catalyst

Ba(Ce,Zr,Pt)O₃-perovskite is a new intelligent catalyst that shows self-regeneration of the precious metal. We previously reported that a Pd-perovskite catalyst, La(Fe,Pd)O₃, regenerates itself through solid solution and segregation of Pd into and out of the perovskite crystal. We investigated the improvement of the oxygen-storage capacity (OSC) of an intelligent catalyst by means of suppressing the grain growth of the precious metal. The new intelligent catalyst is a composite comprising Ba(Ce,Zr,Pt)O₃ perovskite formed on a CeZr oxide. We examined the self-regenerative function of the new material and tested its OSC and catalytic activity after engine aging at high temperature. The new intelligent catalyst was shown to have excellent durability of OSC and excellent catalytic activity.