論文

査読有り 責任著者
2020年2月

Dynamics of the Lattice Oxygen in a Ruddlesden-Popper-type Sr3Fe2O7-d Catalyst during NO Oxidation

ACS CATALYSIS
  • Kazuki Tamai
  • ,
  • Saburo Hosokawa
  • ,
  • Kenya Onishi
  • ,
  • Chikara Watanabe
  • ,
  • Kazuo Kato
  • ,
  • Hiroyuki Asakura
  • ,
  • Kentaro Teramura
  • ,
  • Tsunehiro Tanaka

10
4
開始ページ
2528
終了ページ
2537
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1021/acscatal.9b03857
出版者・発行元
AMER CHEMICAL SOC

In situ observation is a powerful and interesting technique for the characterization of functional materials in their working states. In this study, we used in situ dispersive X-ray absorption fine structure (DXAFS) measurements to observe the lattice oxygen dynamics in SrFeO3-delta and Sr3Fe2O7-delta during NO oxidation. The white-line intensities of Sr K-edge XAFS reflect the concentration of oxygen vacancies, and the lattice oxygen dynamics during NO oxidation are observed. Using a kinetics model, the rate-determining step (RDS) for NO oxidation was found to be an oxygen migration step. The activation energy obtained from the Arrhenius plots for Sr3Fe2O7-delta is much smaller than that obtained for SrFeO3-delta. Sr3Fe2O7-delta with a Ruddlesden-Popper-type layered perovskite can release oxygen with relatively small structural rearrangements. In contrast SrFeO3-delta requires a significant rearrangement of oxygen vacancies to form the brownmillerite phase and the transformation restricts the oxygen release rate. The oxygen storage profiles with O-2 also show that the RDS is the oxygen migration step, although the dissociative adsorption of O-2 suppresses oxygen storage at low temperatures. The lattice oxygen dynamics obtained from the DXAFS measurements, which cannot be obtained from steady-state kinetics experiments, reveal the importance of the perovskite structure for NO oxidation.

リンク情報
DOI
https://doi.org/10.1021/acscatal.9b03857
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000516887400014&DestApp=WOS_CPL
ID情報
  • DOI : 10.1021/acscatal.9b03857
  • ISSN : 2155-5435
  • Web of Science ID : WOS:000516887400014

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