DICP OpenIR
Subject Area物理化学
PREFERENTIAL CO OXIDATION IN H2(PROX) ON IrFe CATALYSTS: 57Fe MOSSBAUER SPECTROSCOPIC STUDY
Liu K(刘阔); Zhang WS(张万生); Wang JH(王军虎); Huang YQ(黄延强); Wang AQ(王爱琴); Zhang T(张涛); Shen JY(沈俭一); Tao Zhang; Jianyi Shen
Conference NameInternational Conference on the Applications of the Mossbauer Effect
Conference Date2009-7-19
2009-07-19
Conference PlaceAustria
Alternative TitleIrFe催化剂上的CO选择氧化(PROX)反应的57Fe穆斯堡尔谱研究
Pages157/1
Department十五室
Funding OrganizationVienna University of Technology
AbstractPreferential CO oxidation in H2 (PROX) has been deemed as a promising way to minimize the CO amount in H2 for the PEMFC. Recently, our group reported that Ir-Fe catalysts were highly active and selective for PROX reaction [1, 2]. It is accepted that Fe plays an important role in activating O2 during PROX reaction, so we made an in situ Mössbauer study on the IrFe catalysts to elucidate the iron state during PROX reaction. Ir/Fe/Al2O3 and Fe/Ir/Al2O3 were obtained through different impregnation sequences, while an Ir-Fe/Al2O3 was prepared by co-impregnation method. Fig. 1 compares the catalytic performances of the three catalysts in the PROX reaction. With the difference in the impregnation sequence, the activity and selectivity varied, following the order of Ir-Fe/Al2O3>Fe/Ir/Al2O3>Ir/Fe/Al2O3. Fig. 2 and Table 1 show the in situ 57Fe Mössbauer spectra of the three catalysts after reduction and PROX reaction. The results show marked differences in the reduction behaviour, pointing out that the impregnating sequence influences the reducibility of these catalysts. The reduction of Ir-Fe/Al2O3 even leads to the formation of FeIr alloy whereas no zero-valent iron is observed for Ir/Fe/Al2O3. The Mössbauer parameters (Fe2+(a), QS = 2.38mm s-1; Fe2+(b), QS = 1.55 mm s-1) are characteristic of two different kinds of Fe2+. However, exposure of the reduced catalysts to PROX gas mixture at 80oC converts Fe2+(b) and FeIr alloy completely to Fe3+. Fe2+(a) and Fe0 decreased as well. After PROX reaction, the overall amount of the reducible iron components in the catalysts, including Fe0 and Fe2+(a), follows the order of Ir-Fe/Al2O3>Fe/Ir/Al2O3>Ir/Fe/Al2O3. This trend is consistent with that of the activity. In conclusion, we suggest that it is FeOx (1≥x) that plays the part of activating O2 during PROX reaction.
Language中文
Document Type会议论文
Identifierhttp://cas-ir.dicp.ac.cn/handle/321008/113514
Collection中国科学院大连化学物理研究所
Corresponding AuthorTao Zhang; Jianyi Shen
Recommended Citation
GB/T 7714
Liu K,Zhang WS,Wang JH,et al. PREFERENTIAL CO OXIDATION IN H2(PROX) ON IrFe CATALYSTS: 57Fe MOSSBAUER SPECTROSCOPIC STUDY[C],2009:157/1.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[刘阔]'s Articles
[张万生]'s Articles
[王军虎]'s Articles
Baidu academic
Similar articles in Baidu academic
[刘阔]'s Articles
[张万生]'s Articles
[王军虎]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[刘阔]'s Articles
[张万生]'s Articles
[王军虎]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.