中国科学院大连化学物理研究所机构知识库
Advanced  
DICP OpenIR  > 中国科学院大连化学物理研究所  > 会议论文
学科主题: 物理化学
题名: Effect of α-Fe2O3 morphology on NO reduction by CO
作者: Mou XL(牟效玲) ;  Li Y(李勇) ;  Huang XM(黄秀敏) ;  Shen WJ(申文杰)
会议名称: 6th International Conference on Environmental Catalysis
会议日期: 2010-9-12
出版日期: 2010-09-12
会议地点: 中国
通讯作者: 申文杰
部门归属: 五室
主办者: 中国科学院生态环境研究中心
摘要: Effect of α-Fe2O3 morphology on NO reduction by CO Xiaoling Mu, Yong Li, Xiumin Huang, Wenjie Shen* State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China *Corresponding author: +86-411-84379085, shen98@dicp.ac.cn Introduction The catalytic reduction of NO by CO is an essential process in the three-way catalytic converter used in abating automobile exhaust, where Pd, Pt and Rh-based noble metals act as the major catalytic components. [1]. Because of the high cost and limited available sources of precious metals, considerable efforts have been made to utilize transition metals and their oxides. Among them, iron oxides seem to be the most promising candidate. Density functional theory analyses have revealed that Fe2O3 clusters are excellent catalysts for CO oxidation and NO reduction [2], but experimental studies on Fe2O3 for NO+CO reaction are reported scarcely. Here, we examined α-Fe2O3 materials with different morphologies (fibrous-like and small nanosheets) for NO reduction by CO, and the fibrous-like α-Fe2O3 shown exceptionally high activity, similar to the precious metal-based catalysts. Experimental The GR1 and GR2 precursors were prepared by precipitation of iron salts with NaOH or Na2CO3 at room temperature. After filtration and washing, the precipitates were calcined at 500 oC for 5 h. The NO+CO reaction was conducted in a continuous-flow fixed-bed quartz reactor with a typical feed gas composition of 0.5% CO/0.5% NO/He (36,000 ml.g-1.h-1). Results and discussion Fig. 1 TEM images of the precursors and oxides: a) GR1; b) α-Fe2O3-GR1; c) GR2; d) α-Fe2O3-GR2 Fig. 2 NO+CO performance on α-Fe2O3 The GR1 and GR2 precursors exhibited characteristic diffraction peaks with different interlayer distances in their XRD patterns but similar fibrous-like morphology judged by TEM observations (Fig.1). After calcination, the GR1 precursor yielded fibrous α-Fe2O3, but the GR2 precursor produced α-Fe2O3 nanosheets. The crystal size of the fibrous α-Fe2O3 and the α-Fe2O3 nanosheets are 12.9 nm and 15.7 nm, corresponding to the surface areas of 87 and 54 m2/g, respectively. When used for NO+CO reaction, the fibrous α-Fe2O3 showed a much higher reactivity than the α-Fe2O3 nanosheets. NO conversion over the former was readily 80% even at 400 oC, but it was only 5% over the later. Considering the crystal sizes and surface areas, it is speculated that the morphology, instead of the surface area, dominated the catalytic performance. Additionally, the fibrous α-Fe2O3 was rather stable for NO reduction for 100 h time-on-stream with a NO conversion of 80-90%, which is almost equivalent to the performance of precious metal-based catalysts under similar conditions. Conclusions Fibrous-like α-Fe2O3 was highly active and stable for NO reduction by CO, giving a similar reaction performance to precious metal-based catalysts. The superior reactivity might be resulted from preferential exposure of active sites for NO reduction in the fibrous-like structure. References [1] S. Roy, M.S. Hedge, G. Madras, Appl. Energy 86 (2009) 2283-2297. [2] B.V. Reddy, S. N. Khanna, Phys. Rev. Lett.93 (2004) 068301-4.
语种: 中文
内容类型: 会议论文
URI标识: http://cas-ir.dicp.ac.cn/handle/321008/114212
Appears in Collections:中国科学院大连化学物理研究所_会议论文

Files in This Item:

There are no files associated with this item.


Recommended Citation:
Mou XL,Li Y,Huang XM,et al. Effect of α-Fe2O3 morphology on NO reduction by CO[C]. 见:6th International Conference on Environmental Catalysis. 中国. 2010-9-12.
Service
 Recommend this item
 Sava as my favorate item
 Show this item's statistics
 Export Endnote File
Google Scholar
 Similar articles in Google Scholar
 [牟效玲]'s Articles
 [李勇]'s Articles
 [黄秀敏]'s Articles
CSDL cross search
 Similar articles in CSDL Cross Search
 [牟效玲]‘s Articles
 [李勇]‘s Articles
 [黄秀敏]‘s Articles
Related Copyright Policies
Null
Social Bookmarking
  Add to CiteULike  Add to Connotea  Add to Del.icio.us  Add to Digg  Add to Reddit 
所有评论 (0)
暂无评论
 
评注功能仅针对注册用户开放,请您登录
您对该条目有什么异议,请填写以下表单,管理员会尽快联系您。
内 容:
Email:  *
单位:
验证码:   刷新
您在IR的使用过程中有什么好的想法或者建议可以反馈给我们。
标 题:
 *
内 容:
Email:  *
验证码:   刷新

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

 

 

Valid XHTML 1.0!
Powered by CSpace