化学传感器：仿真与建模 第1卷 金属氧化物的显微结构表征与建模 下 英文影印版PDF电子书下载

6 MODELING INTERACTIONS OF METAL OXIDE SURFACES WITH WATER&L.Vlcek P.Ganesh A.Bandura E.Mamontov M.Predota P.T.Cumminqs D.J.wesolowski 217

1 Introduction 217

2 Metal Oxide-Water Interactions and Their Study 219

2.1 General Oxide Properties and Surface Processes 220

2.2 Experimental Methods 223

2.3 Computer Simulations 224

2.4 Theoretical Models 228

3 Electronic Structure and Surface Reactions 229

3.1 TiO2 229

3.2 SnO2 233

3.3 ZnO 237

4 Thermodynamic and Structural Aspects of Adsorption 240

4.1 TiO2 240

4.2 SnO2 243

4.3 ZnO 245

5 Dynamics of Adsorbed Water 246

5.1 Fast Processes—Proton Motion 247

5.2 Slow Processes—Molecular Motion 248

6 Perspectives 251

7 Acknowledgments 252

References 252

7 DENSITY FUNCTIONAL THEORY STUDY OF WATER DISSOCIATIVE CHEMISORPTION ON METAL OXIDE SURFACES &C.Zhou H.Cheng 263

1 Introduction 263

2 Catalvtic Water Dissociation on Metal Oxide Surfaces 265

2.1 Water Dissociative Chemisorption on Fe3O4(111)Surfaces 266

2.2 Water Dissociative Chemisorption on Rutile-TiO2(110) Surfaces 275

2.3 Water Dissociative Chemisorption on α-A12O3(100)Surfaces 280

4 Summary 285

5 Acknowledgments 285

References 286

8 FIRST-PRINCIPLES STUDIES OF HYDROGEN SPILLOVER MECHANISMS ON METAL OXIDES&L.Chen M.Yang H.Cheng 293

1 Introduction 293

2 General View of Spillover 294

2.1 Mechanism of Hydrogen Spillover on Metal Oxide 294

2.2 The Role of Noble Metals in the Spillover Effect 295

2.3 The Role of Spillover in Chemical Sensors 296

2.4 Experimental Confirmations of the Presence of Spillover Effect 296

3 Computational Approach 297

4 Hydrogen Spillover in MoO3 297

5 Hydrogen Spillover in Al2O3 306

6 Hydrogen Spillover in WO3 309

7 Summary 312

References 313

9 ADSORPTION AND DIFFUSION OF ADATOMS AND SMALL CLUSTERS ON METAL OXIDE SURFACES&R.Ferrando A.Fortunelli 317

1 Introduction 317

2 Theoretical Methods and Concepts in Metal/Oxide Interaction 320

2.1 Theoretical Methods 320

2.2 Concepts in Metal/Oxide Interaction 322

3 Diffusion of Isolated Adatoms 324

3.1 Energy Barriers for Isolated Adatoms on Flat MgO(001) 324

3.2 Long Jumps in Adatom Diffusion 326

3.3 Diffusion in the Presence of Defects 329

4 Diffusion of Dimers,Trimers,and Tetramers 330

4.1 Dimers 330

4.2 Trimers 333

4.3 Tetramers 334

5 Adsorption and Diffusion on Exotic(Ultrathin) Oxide Substrates 338

5.1 Adsorption 341

5.2 Diffusion 347

6 Conclusions 352

References 353

10 EFFECT OF SXZE ON THE PHASE STABILITY OF NANOSTRUCTURES&S.Li Q.Jiang 363

1 Introduction and Motivation 363

2 Phase Stability and Structural Phase Transition 367

2.1 Crystals and Crystalline Structures 368

2.2 Factors Triggering Phase Transitions 369

2.3 Size Effect on Phase-Transition Pressure and Temperature of Nanostructures 370

2.4 Research on the Thermodynamics of Solid Structural Nanophase Transitions 370

2.5 Effect of Surface:Surface Energy and Surface Stress 371

2.6 Effect of Shape on Phase Stability 372

3 Theoretical Methods for Size-Dependent Phase Stability 372

3.1 Simulation Techniques 373

3.2 Thermodynamics 374

3.3 Applications:Case Studies 382

4 Concluding Remarks 389

References 390

11 SEGREGATION-INDUCED GRAIN-BOUNDARY ELECTRICAL POTENTIAL IN IONIC OXIDE MATERIALS:SIMULATION APPROACHES AND PENDING CHALLENGES&R.L.González Romero J.J.Meléndez Martinez F.L.Cumbrera Hernández D.Gómez Garcia 397

1 Introduction:General Ideas About Segregation Effects in Oxide Materials 397

2 Modeling of Segregation to the Grain Boundaries:Analytical(or Continuum)Approach 398

3 Atomistic Approach:Molecular Dynamics Modeling 408

4 Mesoscopic Approach:Phase-Field Models 414

4.1 Topological Evolution of a Collective of Many Grains 415

4.2 Microstructural Evolution Coupled with Chemical Segregation 417

5 Pending Problems and Future Prospects 418

6 Acknowledgments 419

References 419

INDEX 425