Functional Metal Oxide Nanostructures

Preface 1. New Opportunities on Phase Transitions of Correlated Electron Nanostructures 1.1. Introduction 1.2. Electrical and Structural Transitions in VO2 1.3. Experimental Methods 1.4. Results and Discussions 1.4.1. Phase Inhomogeneity and Domain Organization 1.4.2. Domain Dynamics and Manipulation 1.4.3. Investigation of Phase Transition at the Single Domain Level 1.4.4. Superelasticity in Phase Transition 1.4.5. New Phase Stabilization with Strain 1.4.6. Thermoelectric Across the Metal-Insulator Domain Walls 1.5. Conclusions 2. Controlling the Conductivity in Oxide Semiconductors 2.1. Introduction 2.2. Formalism and Computational Approach 2.3. Results and Discussion 2.3.1. ZnO 2.3.2. SnO2 2.3.3. TiO2 2.4. Concluding Remarks 3. The Role of Defects in Functional Oxide Nanostructures 3.1. Introduction 3.2. Defects in Metal Oxide Nanostructures 3.2.1. Defect Structures in Metal Oxide Nanostructures3.2.2. Imaging Defects in Metal Oxide Nanostructures 3.2.3. Stability of Intrinsic Point Defects in Metal Oxide Nanostructures 3.3. Electrical Response 3.3.1. Point Defects and Charge Carriers 3.3.2. Defects and P-Type Conductivity 3.3.3. Defects and Conduction Mechanisms 3.3.4. Plasmon Response in Defect-Rich Oxide Nanostructures 3.4. Optical Response 3.4.1. Photoluminescence from Point Defects in Oxide Nanostructures 3.4.2. Raman Studies on Oxide Nanostructures 3.4.3. Magneto-Optical Properties of Oxide Nanostructures 3.5. Magnetic Response 3.5.1. Magnetism in Metal Oxide Nanoparticles 3.5.2. Ferromagnetism in Defect-Rich Semiconducting Metal Oxides3.5.3. Spin Polarization in Defect-Rich Metal Oxide Nanostructures 3.5.4. Mechanisms for Magnetism in Metal Oxide Nanostructures 3.6. Defect Engineering in Metal Oxide Nanostructures 3.7. Conclusions 4. Emergent Metal-Insulator Transitions Associated with Electronic Inhomogeneities in Low-Dimensional Complex Oxides 4.1. Introduction 4.2. Experimental Approach 4.2.1. Fabrication of Spatially Confined Oxide Nanostructures 4.2.2. Cryogenic Four-Probe STM 4.3. Results and Discussion4.3.1. Percolative Mott Transition in Sr3(Ru1-xMnx)2O7 4.3.2. Confinement Effects and Tunable Emergent Behavior in La5/8-xPrxCa3/8MnO3 4.4. Conclusion 5. Optical Properties of Nanoscale Transition Metal Oxides 5.1. Physical, Chemical and Size-Shape Tunability in Transition Metal Oxides 5.2. Optical Spectroscopy as a Probe of Complex Oxides 5.3. Quantitative Models 5.3.1. Confinement Models 5.3.2. Descriptions of Inhomogeneous Media 5.3.3. Inhomogeneous Media and Surface Plasmons 5.3.4. Charge and Bonding Models 5.4. Charge-Structure-Function Relationships in Model Nanoscale Materials 5.4.1. Mott Transition in VO2 Revealed by Infrared Spectroscopy 5.4.2. Visualizing Charge and Orbitally Ordered Domains in La1/2Sr3/2MnO4 5.4.3. Discovery of Bound Carrier Excitation in Metal Exchanged Vanadium Oxide Nanoscrolls and Size Dependence of the Equatorial Stretching Modes 5.4.4. Classic Test Cases: Quantum Size Effects in ZnO and TiO2 5.4.5. Optical Properties of Polar Oxide Thin Films and Nanoparticles 5.4.6. Spectroscopic Determination of H2 Binding Sites and Energies in Metal-Organic Framework Materials 5.5. Summary and Outlook 6. Electronic Properties of Post-Transition Metal Oxide Semiconductor Surfaces 6.1. Introduction 6.2. Surface Space-Charge Properties 6.2.1. ZnO 6.2.2. Ga2O3 6.2.3. CdO 6.2.4. In2O3 6.2.5. SnO2 6.3. Bulk Band Structure Origin of Electron Accumulation Propensity 6.4. Conclusion 7. In Search of a Truly Two-Dimensional Metallic Oxide 7.1. Introduction 7.2. Methodology 7.3. Results and Discussion 8. Solution Phase Approach to TiO2 Nanostructures8.1. Introduction 8.2. Approaches 8.2.1. Porous Architectures Through Templated Self Assembly 8.2.2. 1-D Structures from Anodization 8.2.3. Imprinting and Molding 8.2.4. Templated Electrochemical Sythesis 8.2.5. Single Crystalline 1-D Structures by Solution Phase Hydrothermal Growth 8.3. Conclusion 9. Oxide-Based Photonic Crystals from Biological Templates 9.1. Introduction 9.2. Engineered Photonic Crystals 9.2.1. Characteristics of Photonic Band Structure Materials 9.2.2. Photonic Crystals Operating in the Infrared 9.2.3. Photonic Crystals Operating at Visible Frequencies 9.3. Natural Photonic Crystals 9.3.1. Structural Colors in Biology 9.3.2. Structure Evaluation Methods 9.3.3. Examples of Biological Photonic Structures 9.4. Bio-Templated Photonic Crystals 9.4.1. General Considerations 9.4.2. Biotemplating Techniques 9.4.2.1. Deposition and Evaporation Methods 9.4.2.2. Sol-Gel Chemistry Methods 9.4.3. Biotemplated Bandgap Crystals 9.5. Conclusions 10. Low-Dimensionality and Epitaxial Stabilization in Metal Supported Oxide Nanostructures: MnxOy on Pd(100) 10.1. Introduction10.2. Growth of MnxOy Layers on Pd(100) 10.2.1. Low Coverage Regime 10.2.1.1. MnO(111)-like Phases (Oxygen-Rich Regime) 10.2.1.2. MnO(100)-like Phases (Intermediate Oxygen Regime) 10.2.1.3. The Reduced Phases (Oxygen-Poor Regime) 10.2.2. High Coverage Regime 10.2.2.1. Formation of Mn3O4 on MnO(001) 10.2.2.2. Epitaxial Stabilization of MnO(111) Overlayers 11. One Dimensional Oxygen-Deficient Metal Oxides 11.1. Introduction11.2. Oxygen-Deficient 1D-Nano-Ceo2-x and its Applications in the WGS Reaction 11.2.1. Crystal Structure of Cubic-Ceria 11.2.2. Backround of the WGS Reaction 11.2.3. Synthesis of 1D-Ceria 11.2.4. Testing 1D-Ceria for the WGS Reaction 11.3. Sub-Stoichiometric Magneli Phases 1D-TinO2n-1 11.4. Sub-Stoichiometric Chromium Oxide Nanobelts with Modulation Structures 11.5. Summaries 12. Oxide Nanostructures for Energy Storage 12.1. Introduction 12.2. Nano Oxides for Li-Ion Batteries 12.2.1. Spinel LiMn2O4 12.2.2. Manganese Dioxide 12.2.3. Vanadium Pentoxide (V2O5) 12.2.4. Titanium Oxide 12.2.5. Metal Oxides with Displacement Mechanism 12.2.6. Nano-Oxide Coatings 12.3. Nano Oxide for Electrochemical Capacitors 12.3.1. Ruthenium Oxide (RuO2) 12.3.2. Manganese Oxide (MnO2) 12.3.3. Other Metal Oxides 12.3.4. Hierarchical Metal Oxide-Carbon Composites 12.4. Summary 13. Metal Oxide Resistive Switching Memory 13.1. Introduction 13.1.1. Device Operation 13.1.2. Device Characteristics 13.2. Possible Physical Mechanism for Resistive Switching 13.2.1. Conduction Mechanism13.2.2. Electroforming/Set/Reset Process with Oxygen Migration 13.2.3. The Effect of Electrode Materials on Switching Modes 13.2.4. Summary of the Physical Mechanism for Resistive Switching in Metal Oxide Memory 13.3. Performances of Metal Oxide Memory Devices 13.4. Cell Structure of Metal Oxide Memory Arrays 13.5. Summary 14. Nano Metal Oxides for Li-Ion Batteries 14.1. Classification of Electrode Materials for Li-Ion Batteries 14.2. Advantage & Disadvantage of Nano-Electrode Materials 14.3. Nano Metal Oxide Anode Materials 14.3.1. Intercalation Metal Oxides 14.3.2. Conversion Metal Oxide Materials 14.3.3. Displacement Metal Oxide Materials 14.3.3.1. Tin Dioxides Based Anode Materials 14.4. Nano Metal Oxide Cathode Materials 14.4.1. Nanoscale Cathode Materials 14.4.2. Nanostructured Cathode Materials 14.5. Nano Metal Oxides in Electrolyte 14.6. Conclusion and Outlook