Preparation of Ce_xZr_1-xO₂ with Combined Composition for Improved Pd-only Three-way Catalyst

Two special CeO 2 -ZrO 2 composites with combined compositions were prepared by a simple sequential precipitation method. The effect of the combination styles on properties of the supported Pd-only three-way catalysts was investigated by means of X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), nitrogen adsorption/desorption, H 2 -temperature programmed reduction (H 2 -TPR), and oxygen storage capacity measurement (OSC). The results reveal that the structural and textural properties are modified for the two catalysts with compositional heterogeneity. Combined configuration facilitates the formation of Ce 3+ and lattice defects, resulting in improved oxygen mobility, due to strong interaction between the noble metal and the support as well as the synergistic function inside the support. Consequently, the corresponding catalysts show amplified operation windows for the conversions of CO, C 3 H 8 and NO before and after aging, indicating promising application in purification of automobile exhaust gases.