In Situ and Simultaneous Observation of Palladium Redox and Oxygen Storage/Release in Pd/Sr-Fe-O Perovskite Catalysts Using Dispersive XAFS

被引：14

作者：

Kimura, Masao ^{[1
,2
]}

Niwa, Yasuhiro ^{[2
]}

Uemura, Kenichi ^{[1
]}

Nagai, Toru ^{[1
]}

Inada, Yasuhiro ^{[2
]}

Nomura, Masaharu ^{[2
]}

机构：

[1] Nippon Steel Corp Ltd, Adv Technol Res Labs, Futtsu 2938511, Japan

[2] High Energy Accelerator Res Org KEK, Inst Mat Struct Sci, Photon Factory, Tsukuba, Ibaraki 3050801, Japan

来源：

MATERIALS TRANSACTIONS | 2013年 / 54卷 / 02期

关键词：

perovskite; palladium; X-ray absorption fine structure (XAFS); kinetics; time-resolved; redox; X-RAY-ABSORPTION; SPECTROSCOPY; OXIDES;

D O I：

10.2320/matertrans.M2012297

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We have succeeded in in situ and simultaneously observing the redox reaction of palladium and the oxygen storage/release process in a newly developed palladium-promoted Sr-Fe-O (Pd/Sr-Fe-O) catalyst during redox-gas cycles using dispersive X-ray absorption fine structure (XAFS) analysis at 673 K with a time resolution of less than 20 ms. The Pd/Sr-Fe-O catalyst, which exhibits high performance for automotive emission control, has a unique "multi-phase-domain" structure, where a single grain is composed of nano-sized domains of three phases: SrFeO3-delta, Sr4Fe6O13-delta and SrFe12O19-delta. In situ observation has shown a strong correlation between the redox of the palladium and the oxygen storage/release in the Pd/Sr-Fe-O catalyst, and the correlation factors differ between the reduction and oxidation reactions. The oxide phases exhibit a type of "oxygen buffer" effect in the oxidation cycle and delay the formation of Pd-O, resulting in the high performance of the catalyst.

引用

页码：246 / 254

页数：9

共 26 条

[1] Characterization of Catalysts in Reactive Atmospheres by X-ray Absorption Spectroscopy
Bare, Simon R.
Ressler, Thorsten
[J]. ADVANCES IN CATALYSIS, VOL 52, 2009, 52 : 339 - 465
[2] X-RAY-ABSORPTION STUDY OF THE INTERACTION OF HYDROGEN WITH CLUSTERS OF SUPPORTED PALLADIUM
DAVIS, RJ
LANDRY, SM
HORSLEY, JA
BOUDART, M
[J]. PHYSICAL REVIEW B, 1989, 39 (15): : 10580 - 10583
[3] Phase equilibria in the pseudo-binary system SrO-Fe2O3
Fossdal, A
Einarsrud, MA
Grande, T
[J]. JOURNAL OF SOLID STATE CHEMISTRY, 2004, 177 (08) : 2933 - 2942
[4] Correlation between thermodynamic and thermomechanical quantities of selected perovskite-type oxides
Girdauskaite, E.
Vashook, V. V.
Ullmann, H.
Vasylechko, L.
Guth, U.
[J]. JOURNAL OF ALLOYS AND COMPOUNDS, 2009, 477 (1-2) : 468 - 472
[5] X-ray absorption spectroscopy under reaction conditions: suitability of different reaction cells for combined catalyst characterization and time-resolved studies
Grunwaldt, JD
Caravati, M
Hannemann, S
Baiker, A
[J]. PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 2004, 6 (11) : 3037 - 3047
[6] The beamline ID24 at ESRF for energy dispersive X-ray absorption spectroscopy
Hagelstein, M
San Miguel, A
Fontaine, A
Goulon, J
[J]. JOURNAL DE PHYSIQUE IV, 1997, 7 (C2): : 303 - 308
[7] Heck R., 2002, Catalytic air pollution control, V2nd
[8] Heck R. M., 1995, STUD SURF SCI CATAL
[9] CONTRAST TRANSFER OF CRYSTAL IMAGES IN TEM
ISHIZUKA, K
[J]. ULTRAMICROSCOPY, 1980, 5 (01) : 55 - 65
[10] In situ characterization of supported metal catalysts and model surfaces by time-resolved and three-dimensional XAFS techniques
Iwasawa, Y
[J]. JOURNAL OF CATALYSIS, 2003, 216 (1-2) : 165 - 177

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