Pd and Pt ions as highly active sites for the water-gas shift reaction over combustion synthesized zirconia and zirconia-modified ceria

被引：54

作者：

Deshpande, Parag A. ^{[1
]}

Hegde, M. S. ^{[2
]}

Madras, Giridhar ^{[1
,2
]}

机构：

[1] Indian Inst Sci, Dept Chem Engn, Bangalore 560012, Karnataka, India

[2] Indian Inst Sci, Solid State & Struct Chem Unit, Bangalore 560012, Karnataka, India

来源：

APPLIED CATALYSIS B-ENVIRONMENTAL | 2010年 / 96卷 / 1-2期

关键词：

Heterogeneous catalysis; Solid solutions; Oxide ion vacancy; Redox mechanism; Surface processes; Acid-base pairs; FUEL-CELL APPLICATIONS; CATALYTIC-ACTIVITY; REDOX BEHAVIOR; CO OXIDATION; NO REDUCTION; CEO2; SUPPORT; OXYGEN; TEMPERATURE; GOLD;

D O I：

10.1016/j.apcatb.2010.02.004

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Noble metal substituted ionic catalysts were synthesized by solution combustion technique. The compounds were characterized by X-ray diffraction, FT-Raman spectroscopy, and X-ray photoelectron spectroscopy. Zirconia supported compounds crystallized in tetragonal phase. The solid solutions of ceria with zirconia crystallized in fluorite structure. The noble metals were substituted in ionic form. The water-gas shift reaction was carried out over the catalysts. Negligible conversions were observed with unsubstituted compounds. The substitution of a noble metal ion was found to enhance the reaction rate. Equilibrium conversion was obtained below 250 degrees C in the presence of Pt ion substituted compounds. The formation of Bronsted acid-Bronsted base pairs was proposed to explain the activity of zirconia catalysts. The effect of oxide ion vacancies on the reactions over substituted ceria-zirconia solid solutions was established. (c) 2010 Elsevier B.V. All rights reserved.

引用

页码：83 / 93

页数：11

共 64 条

[1] Characterization of CeO2-ZrO2 mixed oxides.: Comparison of the citrate and sol-gel preparation methods [J].

Alifanti, M ;

Baps, B ;

Blangenois, N ;

Naud, J ;

Grange, P ;

Delmon, B .

CHEMISTRY OF MATERIALS, 2003, 15 (02) :395-403

[2] Redox properties of CeO2-MO2 (M=Ti, Zr, Hf, or Th) solid solutions from first principles calculations [J].

Andersson, D. A. ;

Simak, S. I. ;

Skorodumova, N. V. ;

Abrikosov, I. A. ;

Johansson, B. .

APPLIED PHYSICS LETTERS, 2007, 90 (03)

[3]

[Anonymous], CHEM NANOCRYSTALLINE

[4] Combustion synthesis and nanomaterials [J].

Aruna, Singanahally T. ;

Mukasyan, Alexander S. .

CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE, 2008, 12 (3-4) :44-50

[5] Bifunctional catalysts for single-stage water-gas shift reaction in fuel cell applications. Part 1. Effect of the support on the reaction sequence [J].

Azzam, K. G. ;

Babich, I. V. ;

Seshan, K. ;

Lefferts, L. .

JOURNAL OF CATALYSIS, 2007, 251 (01) :153-162

[6] A bifunctional catalyst for the single-stage water-gas shift reaction in fuel cell applications. Part 2. Roles of the support and promoter on catalyst activity and stability [J].

Azzam, K. G. ;

Babich, I. V. ;

Seshan, K. ;

Lefferts, L. .

JOURNAL OF CATALYSIS, 2007, 251 (01) :163-171

[7] Higher catalytic activity of nano-Ce1-x-yTixPdyO2-δ compared to nano-Ce1-x PdxO2-δ for CO oxidation and N2O and NO reduction by CO:: Role of oxide ion vacancy [J].

Baidya, Tinku ;

Marimuthu, A. ;

Hegde, M. S. ;

Ravishankar, N. ;

Madras, Giridhar .

JOURNAL OF PHYSICAL CHEMISTRY C, 2007, 111 (02) :830-839

[8] High Oxygen Storage Capacity and High Rates of CO Oxidation and NO Reduction Catalytic Properties of Ce1-xSnxO2 and Ce0.78Sn0.2Pd0.02O2-δ [J].

Baidya, Tinku ;

Gupta, Asha ;

Deshpandey, Paraag A. ;

Madras, Giridhar ;

Hegde, M. S. .

JOURNAL OF PHYSICAL CHEMISTRY C, 2009, 113 (10) :4059-4068

[9] Noble metal ionic catalysts: correlation of increase in CO oxidation activity with increasing effective charge on Pd ion in Pd ion substituted Ce1-xMxO2-δ (M = Ti, Zr and Hf) [J].

Baidya, Tinku ;

Dutta, Gargi ;

Hegde, M. S. ;

Waghmare, Umesh V. .

DALTON TRANSACTIONS, 2009, (03) :455-464

[10] The Water-Gas-Shift Reaction on Pd/Ceria-Praseodymia: The Effect of Redox Thermodynamics [J].

Bakhmutsky, Kevin ;

Zhou, Gong ;

Timothy, Steven ;

Gorte, Raymond J. .

CATALYSIS LETTERS, 2009, 129 (1-2) :61-65

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