Medium-Coupled Catalysts Meeting Euro III Emission Standards for Gasoline Vehicles

The Ce0.5Zr0.4Y0.1O2 oxygen storage material and La-stabilized alumina (La-Al2O3) were prepared. After aging at 1000$^{o}$C for 5 h, Ce0.5Zr0.4Y0.1O2 has superior textual and oxygen storage properties, and La-Al2O3 has superior textual properties. Medium-coupled Pt-Rh monolithic catalysts were prepared by impregnating Ce0.5Zr0.4Y0.1O2 and La-Al2O3 with H2PtCl6 and RhCl3 solutions and then were washcoated on the cordierite honeycomb. The medium-coupled catalysts show a high low-temperature activity and a high thermal stability. The results from the emission test of JETTA-MT vehicle show fulfillment of Euro III requirements.