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采用水热合成法制备了船形、扁球形及纳米片CeO2-MnOx复合氧化物.并运用低温N2吸脱附、XRD、SEM、TEM、H2-TPR、拉曼光谱、XPS等表征技术对不同形貌CeO2-MnOx复合氧化物的结构与其低浓度CH4催化燃烧反应性能之间的关系进行了关联.结果表明,CeO2-MnOx复合氧化物的形貌与其催化性能密切相关.其中,扁球形CeO2-MnOx复合氧化物的氧空位、Ce3+含量及表面吸附活性氧物种最多,其CH4催化燃烧反应活性最高,540 ℃时,可将CH4完全转化;其次是船形CeO2-MnOx复合氧化物催化剂,540℃时其CH4转化率为94.05%;与前两者相比,纳米片CeO2-MnOx复合氧化物催化剂的氧空位及表面吸附活性氧物种较少,活性较差,相同反应温度下,其CH4转化率仅为89.68%.“,”Ship-like,oblate spheroid and nano sheet CeO2-MnOxmixed oxides were prepared by hydrothermal method and characterized by N2sorption, XRD, SEM, TEM, H2-TPR, Raman spectra and XPS. The relationship between the structure of CeO2-MnOxand their catalytic performance in lean methane combustion were then investigated. The results reveal that the catalytic performance of the mixed CeO2-MnOxoxide was greatly depended on its morphology. Among all of the samples, the mixed oblate spheroid CeO2-MnOxoxides with most oxygen vacancies, Ce3+content and surface active oxygen exhibited the highest activity in lean methane combustion,with a complete CH4conversion at 540℃. Following it,the mixed ship-like CeO2-MnOx oxides catalyst had 94.05% of the CH4conversion at 540℃. On the contrast,the mixed nano sheet CeO2-MnOx oxides catalyst presented the lowest catalytic activity with only 89.68% CH4conversion at the same reaction temprature owing to its lower oxygen vacancies and surface active oxygen.