Authoritative and detailed reference on ambient-pressure x-ray photoelectron spectroscopy for practitioners and researchers starting in the field
Application of Ambient Pressure X-ray Photoelectron Spectroscopy to Catalysis introduces a relatively new analytical method and its applications to chemistry, energy, environmental, and materials sciences, particularly the field of heterogeneous catalysis, covering its background and historical development, its principles, the instrumentation required to use it, analysis of data collected with it, and the challenges it faces.
The features of this method are described early in the text; the starting chapters provide a base for understanding how AP-XPS tracks crucial information in terms of the surface of a catalyst during catalysis. The second half of this book delves into the specific applications of AP-XPS to fundamental studies of different catalytic reactions. In later chapters, the focus is on how AP-XPS could provide key information toward understanding catalytic mechanisms.
To aid in reader comprehension, the takeaways of each chapter are underlined.
In Application of Ambient Pressure X-ray Photoelectron Spectroscopy to Catalysis, readers can expect to find detailed information on specific topics such as: - Going from surface of model catalyst in UHV to surface of nanoparticle catalyst during catalysis - Application of XPS from surface in UHV to surface in gas or liquid phase and fundamentals of X-ray spectroscopy - Significance and challenges of studying surface of a catalyst in gaseous phase and instrumentation of ambient pressure X-ray photoelectron spectrometers - Experimental methods of AP-XPS studies and difference in data analysis between AP-XPS and high vacuum XPS
Ambient Pressure X-Ray Photoelectron Spectroscopy is an ideal resource for entry level researchers and students involved in x-ray photoelectron spectroscopy. Additionally, the text will appeal to scientists in more senior roles in academic and government laboratory institutions in the fields of chemistry, chemical engineering, energy science, and materials science.
Table of Contents
Preface ix
1 From Surface of Model Catalyst in UHV to Surface of Nanoparticle Catalyst During Catalysis 1
2 Application of XPS: from Surface in UHV to Surface in Gas or Liquid Phase 7
2.1 Origin of X-ray Photoelectron Spectroscopy 7
2.2 Applications of XPS to Study Surface in High Vacuum 8
2.3 Applications of XPS to Study Sample in Gas Phase 8
2.4 Applications of XPS to Study Sample in Liquid Phase 8
3 Fundamentals of X-ray Photoelectron Spectroscopy 19
3.1 Principle of XPS 19
3.2 Generation of X-ray 32
3.3 Excitation of Photoelectron and Chemical Shift 36
3.4 Measurements of Energy of Photoelectrons 48
3.5 Measurements of Intensity of Photoelectrons 49
4 Instrumentation of XPS 51
4.1 Regular X-ray Source 51
4.2 X-ray Source with a Monochromator 53
4.3 Energy Analyzer 58
4.4 Detector 63
5 Significance and Challenge of Studying Surface of a Catalyst in Gaseous Phase 67
5.1 Origin of Difference between Surface in UHV and Surface in Reactant Gas 67
5.2 Intrinsic Feature of Catalytic Sites on Surface: Environmental Sensitivity 68
5.3 Ex Situ, Semi-in Situ, and In Situ/Operando Studies of Catalyst Surface at Ambient Pressure of Reactants 69
5.4 Ex Situ, Semi-in Situ, and In Situ/Operando Studies of Catalyst Structure at High Pressure 76
5.5 Technical Challenges in Studying Surface of a Catalyst in Gas Phase 77
6 Instrumentation of Ambient Pressure X-ray Photoelectron Spectrometer 81
6.1 X-ray Source for AP-XPS Studies 81
6.2 Reaction Cell with Capability of Flowing Gas 87
6.3 Differential Pumping Energy Analyzer with High Transmission 96
6.4 Mass Spectrometer with Capability of Measurement of Catalytic Performance 97
7 Experimental Methods of AP-XPS Studies 103
7.1 Leak Test of Reaction Cell 103
7.2 Exclusion of Catalysis by Reaction Cell 103
7.3 Tunning and Control of Sample-Aperture Distance 104
7.4 Sample Heating and Temperature Control 108
7.5 Online Measurement of Reactants and Products 108
7.6 Spectroscopic Titration of Surface Species 110
8 Difference in Data Analysis Between AP-XPS and High Vacuum XPS 113
8.1 Potential Difference in Measuring Atomic Ratio of Two Elements on Catalyst Surface 113
8.2 Difference in Intensity of Photoelectrons Collected by Energy Analyzer 114
8.3 Difference in Resolution and Baseline of Spectrum 114
8.4 Difference in Spectrum between Free Molecules in Gas and Adsorbed Molecules on Surface 116
8.5 Calibration of Nominal Atomic Ratio A/Z of a Catalyst Surface in a Pure Gas 118
8.6 Calibration of Nominal Atomic Ratio A/Z of a Catalyst Surface in a Mixture of Reactants 122
8.7 Calibration of Nominal Atomic Ratio A/Z of a Catalyst Surface in a Pure Gas Obtained at Different Temperature for Fair Comparison 123
9 Significance of Using AP-XPS in Studies of Catalysis 127
9.1 Fundamental of Catalyst Surface 127
9.2 Significance of Characterization of Surface of a Catalyst in Gas Phase 128
9.3 Significance of Using AP-XPS in Fundamental Studies of Catalysis 129
10 CO Oxidation on Single Crystal Model Catalysts 131
10.1 Pt(557) and Pt(332) in CO 131
10.2 CO Oxidation on Pd(100), Pd(111), and Pd(110) 136
10.3 CO Oxidation on Pt(110) and Pt(111) 144
10.4 CO Oxidation on Rh(110) 149
10.5 CO Oxidation on Cu(111) 153
11 CO Oxidation on High Surface Area Catalysts 157
11.1 CO Oxidation on Rh Nanoparticles 157
11.2 CO Oxidation on Ru Nanoparticles 161
12 Hydrogenation of Carbon Dioxide 165
13 Water--Gas Shift 171
13.1 Co3O4 and Pt/Co3O4 171
13.2 Pt, Au, Pd, and Cu Supported on CeO2 Nanorods 175
13.3 CuO--Cr2O3--Fe2O3 179
14 Complete Oxidation of Methane 185
14.1 Complete Oxidation of Methane on NiCo2O4 185
14.2 Complete Oxidation of Methane on NiFe2O4 188
14.3 Complete Oxidation of Methane on NiO with Different Surface Structures 195
15 Partial Oxidation of Methanol 203
15.1 Partial Oxidation of Methanol on Pd1Zn3/ZnO 203
15.2 Partial Oxidation of Methanol on Ir1Zn3/ZnO 207
16 Partial Oxidation of Methane 211
16.1 Partial Oxidation of Methane on Pd/CeO2 211
16.2 Partial Oxidation of Methane on Pt/CeO2 215
16.3 Partial Oxidation of Methane on Rh/CeO2 218
17 Oxidative Coupling of Methane 223
17.1 OCM on Supported Na2WO4 and Hypothesized Active Phase Na2O2 223
17.2 First Observation of Na2O2 through AP-XPS Studies at 800 °C 224
17.3 Formation of a Thin Layer of Na2O2 Supported on Na2WO4 227
18 Dry and Steam Reforming of Methane 231
18.1 Dry Reforming of CH4 on CeO2 Anchored with Ni1 and Ru1 Sites 231
18.2 Steam Reforming of CH4 on CeO2 Anchored with Ni1 and Ru1 Single-atom Sites 237
19 Reduction of NO with CO 243
19.1 Reduction of NO with CO on Co3O4 243
19.2 Reduction of NO with CO on Rh1Co3 Clusters Supported on CoO 247
20 Tuning Catalyst Surfaces for Developing Catalysts 253
20.1 Capability of Compositional Restructuring Checkable with AP-XPS 253
20.2 Tracking Restructuring of Bimetallic Surface under Reaction and Catalytic Conditions for Tuning Catalytic Performance of a Bimetallic Catalyst 255
21 Photocatalysis 263
References 268
Index 271
