Synthesis and characterization of Al2O3-Ce0.5Zr0.5O2 powders prepared by chemical coprecipitation method

Al2O3-Ce0.5Zr0.5O2 catalytic powders were synthesized by the coprecipitation (ACZ-C) and mechanical mixing (ACZ-M) methods, respectively. As-synthesized powders were characterized by XRD, Raman spectroscopy, surface area and thermogravimetric analyses. It was found that the mixing extent of Al3+ ions affected the phase development, texture and oxygen storage capacity (OSC) of the Ce0.5Zr0.5O2 powder. Single phase of ACZ-C could be maintained without phase separation and inhibit α-Al2O3 formation up to 1200 °C. The specific surface area value of ACZ-C (81.5 m2/g) was larger than that of ACZ-M (62.1 m2/g) and Ce0.5Zr0.5O2 (17.1 m2/g) powders, which were calcined at 1000 °C. In comparison with ACZ-C and Al2O3, which were calcined at high temperature (900–1200 °C), it was found that the degradation rate of specific surface area of ACZ-C was lower than that of Al2O3. ACZ-C sample showed a higher thermal stability to resist phase separation and crystallite growth, which enhanced the oxygen storage capacity property for Ce0.5Zr0.5O2 powders.