Effect of Interaction between Ce_0.7Zr_0.3O₂and Al₂O₃on Structural Characteristics, Thermal Stability, and Oxygen Storage Capacity

Abstract

Differences in surface and structural properties, thermal stability and oxygen storage capability (OSC) were investigated from different interactions between Ce0.7Zr0.3O2 and Al2O3 in mixed ceria−zirconia−alumina oxides. Physical techniques such as X-ray diffraction (XRD), BET and pore volume measurement, electron spin resonance (EPR), and mass spectrometry with CO−O2 transient pulses/CO pulses were used for sample characterization. With incorporation of Al3+ into the lattices of Ce0.7Zr0.3O2 at different degrees, which indicates the essential interaction between Ce0.7Zr0.3O2 and Al2O3, we found that mixed oxides have various structural properties. The sample of which most Al3+ incorporated into Ce0.7Zr0.3O2 lattices has intimate interaction, the smallest crystallites, and the highest surface area confirmed through BET and XRD measurements. Meanwhile, EPR detected increasing Ce3+ and OSC is obviously enhanced by the intimate interaction between ceria−zircona and alumina. The results show that the intimate interaction between ceria−zirconia and alumina could modify the structural properties, improve thermal stability, and enhance OSC.