کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1645549 | 1517294 | 2013 | 4 صفحه PDF | دانلود رایگان |
The modifications of CeO2 on the reduction behavior, oxygen storage capacity (OSC), and redox stability of Fe2O3 were investigated. Combination of Fe2O3 with CeO2 strongly improved the low-temperature reducibility of both Fe2O3 and CeO2, evidencing an obvious interaction between cerium and iron oxides during the H2-TPR process. Most of the Fe3+ in single Fe2O3 cannot be restored by the re-oxidation step (OSC step) after the TPR testing, which resulted in a serious decrease in the OSC. On the other hand, the presence of CeO2 significantly enhanced the redox property of Fe2O3: more iron (III) ions were observed in the recycled CeO2/Fe2O3 mixture (Ce/Fe=1/4, labeled Ce20Fe80 sample), and the OSC was obviously improved by the redox treatment. After the first TPR/OSC cycle, the reduction behavior of the recycled Ce20Fe80 sample is highly reversible, indicating good redox stability. This is attributed to the formation of perovskite-type CeFeO3 with excess CeO2, Fe2O3 and Fe in the recycled Ce20Fe80 sample.
► Fe2O3 as a support can strongly improve the surface reducibility of CeO2.
► CeO2 as an additive can enhance the low-temperature reducibility of Fe2O3,
► Oxygen storage capacity of Ce20Fe80 oxide was improved after the redox treatment.
Journal: Materials Letters - Volume 93, 15 February 2013, Pages 129–132