制备方法对Ce_(0.9)Pr_(0.1)O_(2-δ)复合氧化物结构和性能的影响

Effect of Preparation Methods on Structure and Properties of Ce_(0.9)Pr_(0.1)O_(2-δ) Multiple Oxides

采用柠檬酸溶胶—凝胶、硝酸盐分解和共沉淀法制备了Ce0.9Pr0.1O2-δ复合氧化物,考察了复合氧化物的CO氧化活性,并进行了XRD、Raman及TPR表征。结果表明:制备方法对复合氧化物的结构、还原性能及CO氧化活性有较大影响;复合氧化物的CO氧化活性与氧空缺的存在有关,复合氧化晶体中氧空缺越多,越有利于CO氧化;CO的氧化活性与还原峰面积的关系不大,而与还原峰温度有关,还原峰温度越低,其氧化活性越高。

The Ce0.9Pr0.1O2-δ multiple oxides were prepared by the methods of citrate sol-gel, decomposition of nitrate and coprecipitation. Then CO oxidation activity of Ce0.9Pr0.1O2-δ was studied and characterized by XRD, Raman and TPR. The results show that the preparation methods produce a great influence on the structure of multiple oxides, reducing function and CO oxidation activity. CO oxidation activity of Ce0.9Pr0.1O2-δ was related to the existence of oxygen vacancies, and they had a direct bearing. Oxidation activity of CO is not related to the area of the redox peak, but to the temperature of the redox peak. The lower the temperature, the higher the oxidation activity of CO.