Tailored Functional Oxide Nanomaterials

Chiara Maccato, PhD, is Professor of Inorganic Materials and Nanosystems and General and Inorganic Chemistry at Padova University, Italy. She is the coordinator of a morphological characterization laboratory and responsible for a research group on multi-functional inorganic nanomaterials.Davide Barreca, PhD, is Research Director at CNR-ICMATE, Italy, and member of the International EUROCVD Board. His research activity is focused on multi-functional metal-oxide nanosystems, from thin films to ordered nano-arrays, for applications in sensing, energetics and photocatalysis.

• Preface xiii1 Vapor Phase Growth of Metal-Oxide Thin Films and Nanostructures 1Lynette Keeney and Ian M. Povey1.1 Introduction to Vapor Phase Deposition 11.2 Vapor Phase Deposition Methodologies 11.2.1 Chemical Vapor Deposition 21.2.2 Atomic Layer Deposition 21.3 Precursors and Chemistry 31.4 Applications of Metal-Oxide Vapor Phase Deposition 41.4.1 Case Study 1: Ferroelectric Oxide Materials 41.4.1.1 Ferroic Thin Films 51.4.2 Case Study 2: Dielectric Oxide Materials 181.5 Conclusions 27References 282 Addressing Complex Transition Metal Oxides at the Nanoscale: Bottom-Up Syntheses of Nano- objects and Properties 43David Portehault, Francisco Gonell, and Isabel Gómez-Recio2.1 Introduction 432.2 Multicationic Oxides 452.2.1 Layered Oxide-Based Materials 452.2.2 Oxidation States Stable in Organic Media: The Case of Perovskites 502.2.3 Oxidation States Poorly Stable in Organic Media: The Case of Perovskites 542.3 Oxides with Uncommon Metal Oxidation States: The Case of Titanium(III) in Oxides and Extension to Tungsten Oxides 582.3.1 Crystal Structures and Requirements for the Synthesis of Oxides Bearing Titanium(III) Species 592.3.2 Ti2O3 Nanostructures 612.3.3 Mixed Valence Ti(III)/Ti(IV) Oxides: Magnéli Phases 632.3.4 Comparison to Metal Oxidation States Stable in Organic Media: Mixed W(V)/W(VI) Oxides 682.4 Stabilization of New Crystal Structures at the Nanoscale 732.4.1 Hard Templating to Isolate Bulk Metastable Oxides at High Temperatures 742.4.2 Beyond Hard Templating for Isolating Nanostructures of Metastable Oxides 752.4.3 Colloidal Syntheses 752.5 Concluding Remarks 76References 773 Nanosized Oxides Supported on Arrays of Carbon Nanotubes: Synthesis Strategies and Performances of TiO2/CNT Systems 89Maria Letizia Terranova and Emanuela Tamburri3.1 Introduction 893.2 Synthesis Strategies for Preparation of CNT Arrays 903.3 Selected Examples of Supported Nano-oxides 913.4 A Focus on the TiO2/CNT Systems 933.4.1 Synthesis of TiO2 on CNT 993.4.1.1 Wet Chemistry 1003.4.1.2 Vacuum Techniques 1033.5 Concluding Remarks 107References 1084 Computational Approaches to the Study of Oxide Nanomaterials and Nanoporous Oxides 111Ettore Fois and Gloria Tabacchi4.1 Introduction 1114.2 Overview of Theoretical Approaches 1134.3 Molecular Behavior at Nanomaterials Surfaces 1144.3.1 Molecular Interactions on Manganese Oxide Nanomaterials 1144.3.2 Insight on Molecule-to-Material Conversion in Chemical Vapor Deposition 1164.4 Oxide Porous Materials 1214.4.1 Structural Properties 1214.4.2 Behavior Under High-Pressure Conditions 1244.4.3 Hybrid Microporous Functional Materials 1274.5 Outlook and Perspectives 131References 1335 Functional Spinel Oxide Nanomaterials: Tailored Synthesis and Applications 137Zheng Fu and Mark T. Swihart5.1 Introduction and Topic Overview 1375.2 Syntheses 1385.2.1 Vapor Phase 1385.2.1.1 Chemical Vapor Deposition 1385.2.1.2 Atomic Layer Deposition 1385.2.1.3 Spray Pyrolysis 1405.2.1.4 Laser Pyrolysis 1415.2.1.5 Plasma Methods 1425.2.2 Solution Phase 1435.2.2.1 Sol–Gel Methods 1435.2.2.2 Hydrothermal Methods 1435.2.2.3 Thermal Decomposition 1435.2.2.4 Solvothermal Methods 1455.2.3 Solid Phase 1465.2.3.1 Solid-State Thermal Decomposition 1465.2.3.2 Combustion 1475.2.3.3 Ball Milling 1485.2.3.4 High-Temperature Solid Solution Method 1485.3 Structure–Effect Applications 1505.3.1 One-Dimensional (1D) Structures 1515.3.1.1 Nanorods 1515.3.1.2 Nanowires 1545.3.1.3 Nanotubes 1545.3.2 Two-Dimensional (2D) Structures 1595.3.2.1 Nanofilms 1595.3.2.2 Nanosheets 1595.3.2.3 Nanoplatelets 1635.3.3 Three-Dimensional (3D) Structures 1655.3.4 One- and Two-Dimensional (1&2D) Structure 1705.3.5 One- and Three-Dimensional (1&3D) Structures 1715.3.6 Two- and Three-Dimensional (2&3D) Structure 1735.4 Self-Assembled Structures 1755.5 Conclusions and Future Perspectives 180References 1846 Photoinduced Processes in Metal Oxide Nanomaterials 193Nikolai V. Tkachenko and Ramsha Khan6.1 Introduction 1936.2 Photophysics of Bulk MOs 1956.2.1 Energy-Level Structure and Steady-State Spectra 1956.2.2 Photoexcitation and Relaxation Dynamics 2016.2.3 Emission Decay Kinetics, Time-Resolved PL 2036.2.4 Transient Absorption (TA) Spectroscopy 2056.3 Nanostructures 2086.3.1 Quantum Confinement 2086.3.2 Surfaces and Interfaces 2116.4 Photophysical Aspects of MO Applications 2186.4.1 Solar Cells 2186.4.2 Light Emitting Devices 2196.4.3 Photocatalysis 2196.4.4 Photodegradation 2196.4.5 Solar Driven Chemistry 2206.5 Conclusions 220References 2217 Metal Oxide Nanomaterials for Nitrogen Oxides Removal in Urban Environments 229M. Cruz-Yusta, M. Sánchez, and L. Sánchez7.1 Introduction: Photocatalytic Removal of Nitrogen Oxides Gases 2297.2 TiO2-Based Materials 2307.2.1 Tailoring the Energy Band Gap and Edges’ Potentials 2317.2.2 Dopant Elements and Quantum Dots 2347.2.3 Defects, Vacancies, and Crystal Facets in the TiO2 Nanostructure 2357.2.4 Composites/Substrates 2367.2.5 Titanium-Based Oxides 2377.3 Alternative Advanced Photocatalysts 2387.3.1 Bismuth Oxides 2387.3.2 Tin- and Zinc-Based Oxides 2427.3.3 Transition Metal Oxides 2477.4 New Insights into the NOx Gases Photochemical Oxidation Mechanism 2517.5 Field Studies in Urban Areas 2537.5.1 Photocatalytic Construction Materials 2537.5.2 Field Studies of NOx Abatement in Real Environments 2547.6 Conclusions and Perspectives 256References 2598 Synthesis and Characterization of Oxide Photocatalysts for CO2 Reduction 277Fernando Fresno and Patricia García-Muñoz8.1 Introduction 2778.2 Fundamentals of Heterogeneous Photocatalysis 2798.3 Applications of Heterogeneous Photocatalysis 2818.4 Photocatalytic CO2 Reduction: State of the Art and Main Current Issues 2838.4.1 TiO2-Based Photocatalysts for CO2 Reduction 2868.4.2 Other Oxide Photocatalysts 2918.5 Oxide-Based Heterojunctions and Z-Scheme Photocatalytic Systems 2958.5.1 Cocatalysts for CO2 Reduction: Metal-Oxide Synergies 2998.6 Conclusions and Future Perspectives 303References 3039 Functionalized Titania Coatings for Photocatalytic Air and Water Cleaning 317Ksenija Maver, Andraž Šuligoj, Urška Lavrenˇciˇc Štangar, and Nataša Novak Tušar9.1 Introduction 3179.1.1 Titania as a Photocatalyst for Air and Water Cleaning 3179.1.2 Titania Functionalization 3199.1.3 Fabrication of Titania-Based Coatings 3209.1.4 Characterization of Titania-Based Materials 3219.2 Case Studies 3239.2.1 SiO2-Supported TiO2 for Removal of Volatile Organic Pollutants from Indoor Air Under UV Light 3239.2.2 Sn-Functionalized TiO2 as a Photocatalytic Thin Coating for Removal of Organic Pollutants from Water Under UV Light 3259.2.3 SiO2-Supported TiO2 Functionalized with Transition Metals for Removal of Organic Pollutants from Water Under Visible Light 3299.3 Conclusion and Further Outlook 335References 33510 Metal Oxides for Photoelectrochemical Fuel Production 339Gian Andrea Rizzi and Leonardo Girardi10.1 Introduction to Photoelectrochemical Cells 33910.1.1 The Photoelectrochemistry Approach 34410.2 Metal Oxides Photoelectrode Candidate Materials 34710.2.1 Photoanodes 34910.2.2 Photocathodes 34910.3 Tailoring Surface Catalytic Sites and Catalyst Use 35010.4 Metal Oxide Heterostructures 35310.5 Metal Oxides as a Protective Anti-corrosion Layer in Photoelectrodes 35410.6 Evaluation of Photoelectrode Efficiencies 35910.7 Conclusions and Perspectives 365References 36711 Tailoring Porous Electrode Structures by Materials Chemistry and 3D Printing for Electrochemical Energy Storage 379Sally O’Hanlon and Colm O’Dwyer11.1 Strategies for Functional Porosity in Electrochemical Systems 37911.2 Benefits and Limitations of Structural Engineering for Electrochemical Performance 38211.3 Tailoring the Pore Structure of Metal Oxides for Li-ion Battery Cathodes and Anodes 38311.4 Developments in 3D Printing of Porous Electrodes for Electrochemical Energy Storage 38911.5 Porous Current Collectors by 3D Printing 39011.6 Battery and Supercapacitor Materials from 3D Printing 39211.7 Conclusions and Outlook 394References 39612 Ferroic Transition Metal Oxide Nano-heterostructures: From Fundamentals to Applications 405G. Varvaro, A. Omelyanchik, and D. Peddis12.1 Introduction 40512.2 Ferroic Properties of Complex Transition Metal Oxides 40812.2.1 Spinel Ferrites 40812.2.2 Perovskites 41112.2.3 Other Magnetic Oxides 41212.3 Magnetic Oxide Heterostructures 41312.3.1 Hard/Soft Exchange-Coupled Systems 41312.3.2 Ferro(i)magnetic/Antiferromagnetic Systems 41612.3.3 All-Oxide Synthetic Antiferromagnets 41912.4 Artificial Multiferroic Oxide Heterostructures 42112.4.1 Strain Transfer Mechanism 42312.4.2 Charge Modulation Mechanism 42612.4.3 Exchange Interaction Mechanism 42712.5 All-Oxide Spintronic Heterostructures 42712.6 Conclusion and Perspectives 430References 43113 Metal-Oxide Nanomaterials for Gas-Sensing Applications 439Pritamkumar V. Shinde, Nanasaheb M. Shinde, Shoyebmohamad F. Shaikh, and Rajaram S. Mane13.1 Introduction 43913.2 Types of Gas Sensors 44213.3 Metal-Oxide Nanomaterial-Based Gas Sensors 44313.4 Preparation of Metal-Oxide Gas Sensors 44613.4.1 Operation Mechanism 44613.4.2 Morphology-Related Structural Parameters 44813.4.2.1 Grain Size 44813.4.2.2 Pore Size 44913.4.3 Crystallographic Defective and Heterointerface Structures 45313.4.3.1 Defect Structure 45313.4.3.2 Heterointerface Structure 45513.4.4 Chemical Composition 45813.4.5 Addition of Noble Metal Particles 45813.4.6 Humidity and Temperature 46113.5 Gas-Sensing Mechanisms 46213.5.1 Adsorption/Desorption Model 46213.5.1.1 Oxygen Adsorption Model 46413.5.1.2 Chemical Adsorption/Desorption 46713.5.1.3 Physical Adsorption/Desorption 47013.5.2 Bulk Resistance Control Mechanism 47113.5.3 Gas Diffusion Control Mechanism 47213.6 Conclusions and Future Perspectives 474References 475Index 487