Abstract: A series of CeO₂-ZrO₂-Al₂O₃ (CZA) mixed oxides with Nd₂O₃ contents 0–13wt% were prepared by co-precipitation method and characterized by X-ray diffraction (XRD), N₂ adsorption-desorption at low temperature, oxygen pulsing technique (OSC), H₂-temperature programmed reduction (H₂-TPR) and scanning electrical microscope (SEM). The results show that the solubility limit of Nd₂O₃ in the CZA solid solution is about 10wt%. With excessive Nd dopant, the single phase will separate resulting in the formation of Nd_0.5Ce_0.5O_1.75 phase. Furthermore, the proper addition of Nd to CZA solid solution effectively restrains the sintering of oxide particles and greatly improves the thermal stability and redox property of the materials. When the doping amount of Nd₂O₃ in CZA solid solution is 10wt%, the sample has the best textural stability i.e. after calcination at 1000℃ for 5 h, the specific surface area and pore volume achieve 97.14 m²/g and 0.44 mL/g, respectively. For the CZA sample prepared with 7wt% Nd₂O₃ in CZA solid solution, the OSC is the highest in all samples, reaching 938.01 μmol/g and 821.72 μmol/g after calcination at 600℃ and 1000℃, respectively. Meanwhile, the mobility of bulk oxygen is the strongest and the sample has optimal reducibility at low temperature. After aging, the reduction peak temperature can be increased from 465℃ to 483℃. SEM image shows that all the prepared CZA samples have spherical particles and Nd₂O₃ can effectively prevent the agglomeration of particles in the process of high-temperature calcination.

Key words: CeO₂-ZrO₂-Al₂O₃, Nd2O3, textural property, redox property