Metal Oxides Chemistry and Applications

Front cover......Page 1
Preface......Page 12
Editor......Page 14
Contributors......Page 16
Contents......Page 20
1 Molecular Structures of Surface Metal Oxide Species: Nature of Catalytic Active Sites in Mixed Metal Oxides......Page 24
1.2 Supported Metal Oxides......Page 25
1.2.1 Hydrated Surface Metal Oxide Species......Page 26
1.2.2 Dehydrated Surface Metal Oxide Species......Page 30
1.2.3 Surface Metal Oxide Species in Reactive Environments......Page 46
1.4 Bulk Mixed Metal Oxides......Page 47
1.5 Conclusions......Page 48
REFERENCES......Page 49
2.1 INTRODUCTION......Page 54
2.2.2 Ion exchange......Page 56
2.2.6 Other Methods......Page 57
2.3 CATALYST MOLECULAR STRUCTURE......Page 58
2.4 CASE STUDY: TUNGSTATED ZIRCONIUM OXIDE......Page 59
2.4.1 Surface Coverage......Page 61
2.4.2 Molecular Structure of WOx Species......Page 63
2.4.3 Relationship Between WOx Surface Structure and Catalytic Properties......Page 64
2.5.1 Surfactant Templating......Page 67
2.5.2 NP Surfactant Templating......Page 69
2.5.3 Modified Sol–Gel Chemistry......Page 70
2.6 CONCLUSIONS......Page 71
REFERENCES......Page 72
3.1 INTRODUCTION......Page 78
3.2.1 Point Defects......Page 79
3.2.2 Electronic Defects......Page 82
3.2.3 Nonstoichiometry......Page 88
3.3 DIFFUSION AND ELECTRICAL CONDUCTIVITY IN METAL OXIDES......Page 90
3.4 MIXED IONIC AND ELECTRONIC CONDUCTING MATERIALS......Page 95
3.4.1 Transport in MIEC Membranes......Page 96
3.4.2 Fabrication and Characterization of MIEC Membranes......Page 99
REFERENCES......Page 105
4.1 INTRODUCTION......Page 110
4.2 PRINCIPLE OF EELS MEASUREMENTS......Page 112
4.3 IN SITU OBSERVATION OF VALENCE STATE TRANSITION......Page 114
4.4 QUANTIFICATION OF OXYGEN VACANCIES IN CMR OXIDES......Page 117
4.5 REFINING THE CRYSTAL STRUCTURES OF NONSTOICHIOMETRIC OXIDES......Page 118
4.6 IDENTIFYING THE STRUCTURE OF NANOPARTICLES......Page 121
4.7 EXPERIMENTAL APPROACH FOR MAPPING THE VALENCE STATES OF CO AND MN......Page 122
4.8 MAPPING THE VALENCE STATES OF CO USING THE WHITE-LINED RATIO......Page 125
4.9 IN SITU OBSERVATION OF VALENCE STATE TRANSISTION OF MN......Page 129
4.10 PHASE SEPARATION USING THE NEAR-EDGE FINE STRUCTURE......Page 130
4.11 SUMMARY......Page 131
REFERENCES......Page 132
5.1 INTRODUCTION......Page 134
5.2.1 Surface Hydroxyl Site Densities......Page 136
5.2.2 Dehydroxylation of Metal Oxide Surfaces......Page 139
5.3 CARBONATION......Page 141
5.4.1 Solid Solutions......Page 144
5.4.2 Inhomogeneous Distribution of Metal Oxides in Porous Media......Page 147
5.4.3 Aggregation Phenomena in Supported Oxides......Page 150
REFERENCES......Page 151
6 The Electronic Structure of Metal Oxides......Page 156
6.1 INTRODUCTION......Page 157
6.2.1 The Ionic Model......Page 158
6.2.2 Orbital Energies and Covalent Interactions......Page 160
6.3 CALCULATIONS......Page 164
6.4.1 Electronic Structures of Metal Centered Tetrahedra......Page 165
6.4.2 Electronic Structures of Metal Centered Octahedra......Page 169
6.4.3 Octahedra and Tetrahedra Containing dn (n = 0) Transition Metal Cations......Page 171
6.4.4 Electronically Driven Geometric Distortions: 1st and 2nd Order Jahn–Teller Distortions......Page 173
6.5 BASIC CONCEPTS OF ELECTRONIC BAND THEORY......Page 174
6.5.1 The Electronic Band Structure of a One-Dimensional MO Chain......Page 175
6.5.2 Density of States Plots......Page 180
6.5.3 Conductivity, Carrier Mobility, and Their Relationship to the Band Structure......Page 181
6.5.4 The Electronic Band Structure of a Two-Dimensional CuO2− Layer......Page 183
6.5.5 The Electronic Band Structure of a Three-Dimensional WO3 Cubic Lattice......Page 186
6.6 ELECTRONIC BAND STRUCTURES OF PEROVSKITES......Page 190
6.6.1 Cubic Perovskites with Transition Metal Ions: Semiconductors and Metals......Page 191
6.6.2 Cubic Perovskites with MainGr oup Ions......Page 194
6.6.3 Distorted Perovskites: NaTaO3, CaSnO3, and CdSnO3......Page 196
6.7 ELECTRONIC BAND STRUCTURES OF BINARY OXIDES USED AS TRANSPARENT CONDUCTORS......Page 200
6.7.1 The Electronic Structure of SnO2......Page 201
6.7.2 The Electronic Structure of ZnO......Page 205
6.7.3 The Electronic Structure of CdO......Page 207
6.7.4 The Link between Conduction Band Width and OxygenCoor dination......Page 209
6.7.5 Generality of the Anion Coordination — Bandwidth Connection......Page 212
REFERENCES......Page 213
7.1 INTRODUCTION......Page 218
7.2.1 Electronic Structure of Metal Oxides......Page 220
7.2.2 Magnetic Interactions in Metal Oxides......Page 223
7.2.3 Magnetic Properties in Cuprates and Manganites......Page 225
7.3.1 Optical Conductivity......Page 228
7.3.2 Raman Scattering......Page 230
7.3.3 Resonant X-Ray Scattering......Page 232
REFERENCES......Page 234
8.1 INTRODUCTION......Page 238
8.2 REDOX CATALYSTS......Page 239
8.3 ACID–BASE AND REDOX PROPERTIES......Page 242
8.4 NATURE OF OXYGEN SPECIES......Page 243
8.5 STUDIES OF REDOX CHARACTERISTICS......Page 245
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8.6.1 Vanadium Oxide-Based Catalysts......Page 248
8.6.2 Cerium Oxide-Based Catalysts......Page 254
8.6.3 Redox Behavior of Mixed Oxides......Page 257
8.7 CONCLUSIONS......Page 258
REFERENCES......Page 259
9 The Surface Acidity and Basicity of Solid Oxides and Zeolites......Page 270
9.1 INTRODUCTION......Page 271
 9.2.1 Definitions of Acidity and Basicity......Page 272
9.2.2 Ionicity/Covalency and the Structures of Solid Oxides......Page 273
9.2.3 Acidity and Basicity on the Ideal Surface of a Solid Oxide......Page 275
9.2.4 Amount, Strength, and Distribution of Surface Acid and Basic Sites on the Ideal Surface of a Solid Oxide......Page 276
9.3.1 Molecular Probes for Surface Acidity and Basicity Characterization......Page 277
9.3.2 Quantitative Adsorption of Probe Molecules from Gas and Liquid Phases......Page 279
9.3.3 Calorimetric Methods......Page 280
9.3.4 Temperature Programmed Desorption Methods......Page 281
9.3.5 IR Spectroscopic Methods......Page 282
9.3.6 Nuclear Magnetic Resonance (NMR) Spectroscopic Methods......Page 286
9.3.8 Catalytic Probe Reactions......Page 288
 9.4.1 Lewis Acid Strength......Page 289
9.4.2 Density of Lewis Sites......Page 291
9.4.4 Brønsted Acidity......Page 292
9.5.1 The Aluminas......Page 295
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9.5.3 Cationic Zeolites and Other Metal-Containing Zeolite-Like Structures......Page 316
9.5.4 Sulfated and Tungstated Zirconia: True Superacids?......Page 319
9.5.5 Solid Basic Catalysts: Oxides Containing Alkali, Alkali-Earth, and Rare Earth Cations......Page 321
REFERENCES......Page 323
10 Optical Basicity: A Scale of Acidity/Basicity of Solids and Its Application to Oxidation Catalysis......Page 342
10.1 INTRODUCTION......Page 343
10.2.1 After Duffy......Page 345
10.2.2 Mixed Oxides......Page 348
10.2.3 Surface Evaluation of Optical Basicity......Page 350
10.3 IONIZATION POTENTIAL AND SELECTIVITY......Page 352
10.4.1 Correlations between A And Experimental Values of Selectivity......Page 354
10.4.2 Linear [AI. A] Correlations: Alkanes and Alkyl-Aromatics......Page 355
10.4.4 Combustion of Paraffins and of Olefins......Page 360
10.5 THEORETICAL ASPECTS......Page 364
10.5.1 Attempts to Give a Thermodynamic Definition of Optical Basicity......Page 365
10.5.2 Attempts to Account for Linear Relationships Between Ionization Potential of Molecules and Optical Basicity of Catalysts......Page 366
10.6 CONCLUSION......Page 368
REFERENCES......Page 369
11 Investigation of the Nature and Number of Surface Active Sites of Supported and Bulk Metal Oxide Catalysts through Methanol Chemisorption......Page 376
11.1 INTRODUCTION......Page 377
11.2.1 Redox Sites Selective Molecular Probes......Page 378
11.2.2 Acid–Base Sites Selective Molecular Probes......Page 381
11.2.3 Super-Acid Sites of Heteropoly-Oxo Compounds......Page 382
11.3 DESIGNING A TAILORED MOLECULAR PROBE FOR A SPECIFIC APPLICATION......Page 383
11.3.1 Surface Reaction Mechanism of Methanol Adsorption-Reaction on Oxide Surfaces......Page 384
11.3.2 Saturation of the Oxide Surface with Reactive Surface Intermediate Species......Page 388
11.3.3 Measurementof the Amountof Surface Reactive Intermediate Species for the Determination of the Density of Surface Active Sites......Page 390
11.4.1 Stoichiometry of Methanol Adsorption and “Ligand Effect” of Monolayer Supported Metal Oxide-Based Catalysts......Page 392
11.4.2 Surface Morphology of Bulk Metal Oxide Catalysts......Page 394
11.4.3 Surface Composition of Bulk Metal Molybdate and Vanadate Catalysts......Page 396
11.4.4 Monolayer Supported versus Bulk Oxide Catalysts: Which is More Active?......Page 398
11.5 ISOPROPANOL AS A PROBE MOLECULE: REDOX VERSUS ACID PROPERTIES OF OXIDE CATALYSTS......Page 401
11.5.1 Isopropanol Adsorption over One-Component Bulk Metal Oxides......Page 402
11.5.2 Super-Acid Properties of Complex Heteropoly-Oxo Metallates......Page 404
11.6 FINAL REMARKS: THE FUTURE ON SURFACE SCIENCE THROUGH MOLECULAR PROBES......Page 408
REFERENCES......Page 409
12.1 INTRODUCTION......Page 414
12.2 STRATEGIES IN HIGH-THROUGHPUT EXPERIMENTATION......Page 416
12.2.1 Substrate-Based Approaches......Page 417
12.2.2 Substrate-Free Approaches......Page 418
12.3 SPECIFIC TECHNIQUES 12.3.1 Sputter or Evaporation Procedures......Page 419
12.3.2 Hydrothermal Reactions......Page 420
12.3.3 Sol–Gel Synthesis......Page 422
12.3.4 Precipitation Procedures......Page 423
12.3.5 Activated Carbon Route......Page 424
12.3.6 Split-and-Pool Synthesis......Page 425
REFERENCES......Page 431
13 Propane Selective Oxidation to Propene and Oxygenates on Metal Oxides......Page 436
13.1 INTRODUCTION......Page 437
13.2 ACRYLIC ACID — INDUSTRIAL APPLICATION AND PRODUCTION......Page 438
13.3 CHARACTERISTICS OF PROPANE OXIDATION REACTION......Page 440
13.4 CATALYSTS FOR SELECTIVE OXIDATION OF PROPANE......Page 444
13.4.1 Vanadium Phosphorous Oxides Catalysts......Page 445
13.4.2 Heteropolyoxometallic Compounds......Page 447
13.4.3 Multicomponent Mixed Metal Oxides......Page 451
13.4.4 Zeolites and Molecular Sieves......Page 457
13.5.1 Experimental......Page 461
13.5.2 Results......Page 463
CONCLUSIONS......Page 475
REFERENCES......Page 478
14.1 INTRODUCTION......Page 486
14.2 CH4 ACTIVATION OF METAL OXIDES......Page 488
14.3 METHANE COMBUSTION 14.3.1 Single Metal Oxides......Page 489
14.3.2 Double Oxides......Page 490
14.3.3 Doped Metal Oxides......Page 492
14.3.4 Hexaaluminate Materials......Page 493
14.4 OXIDATIVE COUPLING OF METHANE......Page 494
14.4.1 Catalytic Systems......Page 495
14.4.3 Prospects and Opportunities......Page 496
14.5.1 Silica......Page 497
14.5.2 RedoxOx ides......Page 499
OUTLOOK......Page 504
REFERENCES......Page 505
15.1 INTRODUCTION......Page 514
15.2 MECHANISMS OF THE ODH REACTIONS......Page 516
15.3.1 ODH of Ethane......Page 521
15.3.2 ODH of Propane......Page 525
15.3.3 ODH of n-Butane......Page 527
15.3.4 ODH of Isobutane......Page 529
15.3.5 Summary......Page 530
REFERENCES......Page 533
16.1 INTRODUCTION......Page 540
16.2 ROLE OF METAL-CARBENES IN METATHESIS REACTIONS......Page 543
16.3.1 Rhenium-Based Metathesis Catalysts......Page 544
16.3.2 Molybdenum-Based Metathesis Catalysts......Page 550
16.3.3 Tungsten-Based Metathesis Catalysts......Page 552
16.4 OLEFIN METATHESIS OVER NONTRANSISTION METAL OXIDES......Page 553
16.5 REACTION MECHANISM 16.5.1 ReactionP athways......Page 555
16.5.2 Theoretical Calculations......Page 557
16.6 SUMMARY......Page 558
REFERENCES......Page 559
17.1 INTRODUCTION......Page 566
17.2 VOCS OXIDATION OVER METAL OXIDES......Page 567
17.2.1 Perovskite Oxidesin VOCsOxidation......Page 573
17.2.3 Oxidation of Halogen Containing VOCs......Page 576
17.4 Carbon Deposition and VOCs Oxidation Activity......Page 578
REFERENCES......Page 580
18.1 INTRODUCTION......Page 592
18.2.1 Hydrogen......Page 594
18.2.2 Carbon Monoxide......Page 595
18.3 CARBON MONOXIDE HYDROGENATION......Page 599
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18.3.2 Strong Metal-Support Interactions......Page 601
18.3.3 Mixed Oxides......Page 602
18.4 HYDROGENATION OF CO/CO2 MIXTURES......Page 604
18.5 CARBON DIOXIDE HYDROGENATION 18.5.1 ActiveSiteand Roleof ZnO......Page 605
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18.6 IN SITU STUDIES......Page 610
18.7 SUMMARY......Page 611
REFERENCES......Page 612
19.1 INTRODUCTION......Page 618
19.2 DESIGN AND DEVELOPMENT OF SECOND-GENERATION TI02 PHOTOCATALYSTS THAT CAN OPERATE UNDER VISIBLE LIGHT IRRADATION......Page 620
19.3 PHOTOCATALYTIC PERFORMANCE OF TITANIUM OXIDE-BASED THIN FILM CATALYSTS......Page 624
19.4 PHOTOCATALYTIC DECOMPOSITION OF WATER INTO H AND 02 USING TI02 THIN FILM PHOTOCATALYSTS......Page 630
19.5 LOCAL STRUCTURES OF THE ACTIVE SURFACE SITES OF TI-MCM-41 CATALYSTS AND THEIR PHOTOCATALYSTS REACTIVITY......Page 634
REFERENCES......Page 638
20 Photocatalytic Activity for Water Decomposition of RuO2-Dispersed p-Block Metal Oxides with d10 Electronic Configuration......Page 646
20.1 INTRODUCTION......Page 647
20.2 EXPERIMENTAL CONDITIONS......Page 648
20.3.2 Alkaline Earth Metal Indates[18]......Page 649
20.3.3 Lanthanum and Gadolinium Indates......Page 654
20.3.5 Role of the Local Structure of InO6......Page 655
20.3.6 Electronic Structures......Page 658
20.4 ZINC GALLATES, ZNGA2O4 [34]......Page 663
20.5 ZINC GERMANATE, Zn2GeO4 [37]......Page 670
20.6 ALKALINE EARTH METAL STANANTES ND ANTIMONATES......Page 673
20.7 CONCLUSION......Page 679
REFERENCES......Page 680
21.1 INTRODUCTION......Page 684
21.2.1 Ammonia versus Hydrocarbon as the Selective Reductant......Page 686
21.2.2 SCR on Metal Oxide Coupled to NonThermal Plasma......Page 688
21.2.3 NH3-SCR Processes for the Emissions from Combustion and Nitric Acid Plants......Page 689
21.2.4 The Question of Catalyst Activity in the NH3-SCR Process......Page 690
21.3.1 Metal Oxide Catalysts for the SCR-NH3 Process......Page 691
21.3.2 Reaction Mechanisms and Microkinetic Approaches to the SCR-NH3 Reaction......Page 694
21.4 SCR-HC......Page 697
REFERENCES......Page 702
22.1 INTRODUCTION......Page 706
22.2 SENSOR PERFORMANCE......Page 712
22.3 PRINCIPLE OF OPERATION......Page 718
22.3.1 Surface Chemistry and Charge Transfer......Page 722
22.3.2 Transduction: Contribution of Different Sensor Parts in the Sensing Process and Subsequent Transduction......Page 742
22.4 MULTIPLE FEATURE EXTRACTION APPROACH FOR GAS SENSING......Page 749
22.5 Conclusions......Page 751
REFERENCES......Page 752
23.1 INTRODUCTION......Page 762
23.2 CHOICE OF MATERIALS FOR SOFC ANODE......Page 764
23.3 FUELS FOR HIGH TEMPERATURE FUEL CELLS......Page 765
23.4.1 Reforming......Page 766
23.4.2 Direct Oxidation......Page 768
23.5.2 Cu–Zirconia and Cu–Ceria Anode Materials......Page 769
23.5.3 Alternative Anode Materials......Page 772
23.6 ANODE MATERIALS FOR DIRECT HYDROCARBON FUEL CELLS......Page 779
23.7 MICROSTRUCTURAL COMPROMISE......Page 781
FUTURE ANODE DEVELOPMENT......Page 782
REFERENCES......Page 783
Index......Page 790
Back cover......Page 808