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分别利用氨水共沉淀法和柠檬酸溶胶-凝胶法制备稀土储氧材料(Ce0.6Zr0.4O2)0.5(Al2O3)0.5,并用XRD、BET、H2-TPR、SEM和EDX等手段研究制备方法对(Ce0.6Zr0.4O2)0.5(Al2O3)0.5的晶相结构、比表面积、平均孔径、孔容、储氧性能、还原性能、样品各组分含量以及颗粒形貌的影响。结果表明两种方法制备样品均为立方晶相的CeO2-ZrO2-Al2O3固溶体,无Al2O3的晶相。但与氨水共沉淀法比较,柠檬酸溶胶-凝胶法制备样品的比表面积、孔容较大,储氧性、还原性和热稳定性能较高。SEM和EDX测试结果表明,氨水共沉淀法制备样品有明显的聚集现象,而柠檬酸溶胶-凝胶法制备样品的颗粒粒径小,分布均匀,且原子组成更接近理论值。
The rare earth oxygen storage material (Ce0.6Zr0.4O2) 0.5 (Al2O3) 0.5 was prepared by aqueous coprecipitation method and citric acid sol-gel method. The preparation method was studied by XRD, BET, H2-TPR, SEM and EDX (Ce0.6Zr0.4O2) 0.5 (Al2O3) 0.5, the specific surface area, the average pore diameter, the pore volume, the oxygen storage performance, the reduction performance, the content of each component of the sample and the morphology of the particles. The results show that the CeO2-ZrO2-Al2O3 solid solution with cubic phase is prepared by both methods without any Al2O3. However, compared with the co-precipitation method of ammonia, the sample prepared by citric acid sol-gel method has larger specific surface area, larger pore volume and higher oxygen storage, reduction and thermal stability. The results of SEM and EDX show that the samples prepared by ammonia co-precipitation have obvious aggregation phenomenon, while the samples prepared by the citric acid sol-gel method have small particle size and uniform distribution, and the atomic composition is closer to the theoretical value.