采用两种不同的沉淀方法制备出CeO2和一系列的CexZr1-xO2(x=0.8、0.5、0.1)固溶体,并应用XRD和H2-TPR对500℃焙烧和1000℃老化的样品进行研究.结果表明制备方法对CexZr1-x O2固溶体的晶相结构和还原性能有重要影响.两种方法制备的Ce0.8Zr0.2O2均为立方晶相,氨水沉淀法制备的Ce0.5Zr0.5O2为立方晶相和四方晶相共存的结构,而NaOH溶液沉淀法制备的Ce0.5Zr0.5O2为单纯的四方晶相,而且此方法制备的Ce0.1Zr0.9O2在高温条件下晶相结构不稳定,出现单斜晶相.与氨水沉淀法相比,NaOH溶液沉淀法制备500℃焙烧样品的还原性能明显较强,而在1000℃高温老化后,两者还原性能均有所降低.
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