List of contributors

Preface

Part I     Introduction

1             Metal Oxides and Specific Functional Properties at the Nanoscale

               Oliver Diwald

1.1 A Cross-Sectional Topic in Materials Science and Technology

1.2 Metal Oxides: Bonding and Characteristic Features

1.3 Regimes of Size-Dependent Property Changes and Confinement Effects

1.4 Distribution of Nanoparticle Properties

1.5 Structure and Morphology

1.5.1 Confinement and Structural Disorder

1.5.2 Surface Free Energy Contributions and Metastability

1.5.3 Shape

1.6 Electronic Structure and Defects

1.6.1 Size-Dependent Defect Formation Energies and Their Impact on Surface Reactivity

1.7 Surface Chemistry

1.8 Metal Oxide Nanoparticle Ensembles as Dynamic Systems

1.9 Organization of This Book

2             Application of Metal Oxide Nanoparticles and their Economic Impact

Karl-Heinz Haas

2.1 Introduction

2.1.1 Nanomaterials and Nanoobjects

2.1.2 Selection of Metal Oxide Nanoparticles

2.2 Scientific and Patent Landscape

2.3 Types of Metal Oxide Nanoparticles, Properties, and Application Overview

2.4 Use Forms of Metal Oxide Nanoparticles and Related Processing

2.4.1 Metal Oxide Nanoparticle Powders for Ceramics

2.4.2 Metal Oxide Nanoparticle Dispersions

2.4.3 Composites

2.4.3.1 Polymer Based (Bulk and Coatings)

2.4.3.2 Metal Reinforcement

2.4.4 Combination with Powders of Micrometer Sized particles

2.5 Application Fields of Metal Oxide Nanoparticles

2.5.1 Agriculture

2.5.2 Sensors and Analytics

2.5.3 Automotive

2.5.4 Biomedical/Dental

2.5.4.1 Therapy

2.5.5 Catalysis

2.5.6 Consumer Products: Cosmetics, Food, Textiles

2.5.7 Construction

2.5.8 Electronics Including Magnetics

2.5.9 Energy

2.5.10 Environment, Resource Efficiency, Processing

2.5.11 Oil Field Chemicals and Petroleum Industries

2.5.12 Optics/Optoelectronics and Photonics

2.6 Economic Impact

2.7 Conclusion and Outlook

Part II    Particle Synthesis: Principles of Selected Bottom-up Strategies

3 Nanoparticle Synthesis in the Gas Phase

Matthias Niedermaier, Thomas Schwab, and Oliver Diwald

3.1.Introduction

3.2.Some Key Issues of Particle Formation in the Gas Phase and in Liquids

3.3.Gas Phase Chemistry, Particle Dynamics, and Agglomeration

3.4.Gas-to-Particle Conversion

3.4.1.Physical Processes

3.4.2.Chemical Processes

3.5.Particle-to-Particle Conversion

3.5.1 Approaches and Precursors

3.5.2.Particle Formation

3.5.3.Experimental Realization

3.5.4.Spray Pyrolysis and Flame-Assisted Spray Pyrolysis

3.6.Gas Phase Functionalization Approaches

4             Liquid-Phase Synthesis of Metal Oxide Nanoparticles

Andrea Feinle and Nicola Hüsing

4.1 Introduction

4.2 General Aspects

4.2.1 Liquid-Phase Chemistry

4.2.2 Nucleation, Growth, and Crystallization

4.3 Synthetic Procedures

4.3.1 (Co)Precipitation

4.3.2 Sol–Gel Processing

4.3.3 Polyol-Mediated Synthesis/Pechini Method

4.3.4 Hot-Injection Method

4.3.5 Hydrothermal/Solvothermal Processing

4.3.6 Microwave-Assisted Synthesis

4.3.7 Sonication-Assisted Synthesis

4.3.8 Synthesis in Confined Spaces

4.4 Summary

5             Controlled Impurity Admixture: From Doped Systems to Composites

Alessandro Lauria and Markus Niederberger

5.1 Introduction

5.2 Liquid-Phase Synthesis of Doped Metal Oxide Nanoparticles

5.3 Gas-Phase Synthesis of Doped Metal Oxide Nanoparticles

5.4 Solid-State Synthesis of Doped Metal Oxide Nanoparticles

5.5 Phase Segregation: Formation of Heterostructures

5.6 Core/Shell and Heteromultimers

5.7 Summary and Conclusions

Part III   Nanoparticle Formulation: A Selection of Processing and Application Routes

6             Colloidal Processing

Thomas Berger

6.1 Towards Complex Shaped and Compositionally Well-Defined Ceramics: The Need for Colloidal Processing

6.2 Colloidal Processing Fundamentals

6.2.1 Interparticle Forces

6.2.1.1 Electric Double Layer Forces

6.2.1.2 Polymer-Induced Forces

6.2.2 Forming and Consolidation Techniques

6.2.2.1 Drained Casting Techniques

6.2.2.2 Tape-Casting Techniques

6.2.2.3 Constant Volume Techniques

6.2.2.4 Drying and Cracking

6.3 Rheology of Suspensions

6.4 Electrostatic Heteroaggregation of Metal Oxide Nanoparticles

6.4.1 Modification of Colloidal Stability by Heteroaggregation

6.4.2 Structure Evolution upon Heteroaggregation in Binary Nanoparticle Dispersions

6.4.3 Rheological Properties of Binary Heterocolloids

6.4.4 Functional Properties of Heteroaggregates

6.5 Ice-Templating-Enabled Porous Ceramic Structures: A Case Example of the Impact of Nanoparticles on Colloidal Processes and Material Properties

6.5.1 Ice-Templating of Colloidal Particles

6.5.2 Capabilities of Metal Oxide Nanoparticles in Ice-Templating

6.5.2.1 Optimization of the Mechanical Properties of Green Bodies and Sintered Parts

6.5.2.2 Hierarchical Porosity and High Surface Area Materials

6.5.2.3 Triple Phase Boundaries Between Entangled Percolating Networks Consisting of Two Inorganic Phases and a Hierarchical Pore System

6.6 From Colloidal Processing to Nanoparticle Assembly: Towards the Control of Particle Arrangement Over Several Length Scales

7             Fabrication of Metal Oxide Nanostructures by Materials Printing

Petr Dzik, Michal Veselý, and Oliver Diwald

7.1 Introduction

7.2 Traditional Coating and Printing Techniques

7.3 Inkjet Printing

7.3.1 A Brief Introduction into IJP Technology and the Process Scheme

7.3.2 Functional Ink Formulation Issues

7.3.3 Drop Generation

7.3.4 Drop Interaction with the Substrate

7.3.5 Drop Drying and Pattern Formation

7.3.6 Printing Quality

7.3.7 Equipment and Printing Devices

7.4 Printing of Metal Oxide Structures: The Materials Aspect

7.4.1 Insulating Metal Oxides

7.4.2 Semiconducting Metal Oxides

7.4.3 Conducting Metal Oxides

7.5 Examples for Complex Printed Functional Structures: The Device Aspect

7.5.1 Printed Photoelectrochemical Cell

7.5.2 Flexible pH Sensors by Large Scale Layer-by-layer Inkjet Printing

7.6 Conclusions and Outlook

8             Nanoscale Sintering

Kathy Lu and Kaijie Ning

8.1 Background

8.2 Challenges and New Aspects of Nanoparticle Material Sintering

8.3 Questionable Nature of Existing Sintering Theories

8.4 3D Reconstruction

8.4.1 Focused Ion Beam Cross-Sectioning and SEM Imaging

8.4.2 X-ray Microtomography

8.5 Functions of Pores

8.6 Sintering of Small Features

8.6.1 New Sintering Questions

8.6.2 Role of Pore Number in Small Feature Sintering

8.6.3 Grain Boundary Diffusion vs. Grain Boundary Migration in Small Feature Sintering

8.6.4 Ceramic Type Effect on Small Feature Sintering

8.6.5 Atmosphere Effect on Small Feature Sintering

8.7 Summary

Part IV   Metal Oxide Nanoparticle Characterization at Different Length Scales

9             Structure: Scattering Techniques

Günther J. Redhammer

9.1 Introduction

9.1.1 Scattering and Diffraction

9.1.2 What to Learn from a Diffraction Experiment?

9.2 Theoretical Background

9.2.1 Crystal Lattice, Planes, and Bragg’s Law

9.2.1.1 Crystal Planes and Interplanar Distance

9.2.1.2 The Reciprocal Lattice

9.2.1.3 Bragg’s Law

9.2.2 The Intensity of a Bragg Peak

9.2.3 The Profile of a Bragg Peak

9.2.3.1 Instrumental Broadening

9.2.3.2 Sample Broadening

9.2.3.3 Analytical Description of Peak Shapes

9.3 Experimental Setup

9.3.1 Single vs. Polycrystalline Samples

9.3.2 Powder Diffraction Methods

9.3.2.1 Reflection Geometry

9.3.2.2 Transmission Geometry

9.3.2.3 Grazing Incident Diffraction (GID)

9.3.2.4 Sample Preparation

9.4 Some Selected Applications

9.4.1 Qualitative Phase Analysis

9.4.2 Quantitative Phase Analysis – The Rietveld Method

9.4.3 Microstructure Analysis: Size and Strain

9.5 X-ray Diffraction on Magnetite Nanoparticles

9.6 Conclusion

10           Morphology, Structure, and Chemical Composition: Transmission Electron Microscopy and Elemental Analysis

Joanna Gryboś, Paulina Indyka, and Zbigniew Sojka

10.1 Size, Shape, and Composition of Oxide Nanoparticles

10.2 Interaction of the Incident Electrons with a Specimen

10.3 The Transmission Electron Microscope

10.3.1 Microscope Design and Operation Modes

10.3.2 Contrast Type and Image Formation

10.3.3 Resolution Limits of TEM Images

10.4 Imaging and Analysis of Morphology

10.4.1 Sample Preparation

10.4.2 Shape Retrieving

10.4.2.1 Aligned Nanocrystals

10.4.2.2 Randomly Oriented Nanocrystals

10.4.3 Particle Size Determination

10.5 Crystallographic Phase Identification – Electron Diffraction

10.5.1 Bragg Condition – Kinematical and Dynamical Diffraction

10.5.2 Selected Area Electron Diffraction (SAED)

10.5.3 Nanodiffraction

10.6 Chemical Composition Mapping – EDX and EELS Nanospectroscopy

10.6.1 Correlating Image with Spectroscopic EDX and EELS Information – Data Cubes

10.6.2 Composition Mapping with EDX Spectroscopy

10.6.3 Chemical State Imaging with EELS Spectroscopy

11           Electronic and Chemical Properties: X-ray Absorption and Photoemission

Paolo Dolcet and Silvia Gross

11.1 Introduction and Scope of the Chapter

11.2 Basics of X-rays – Matter Interaction

11.3 X-ray Photoelectron Spectroscopy (XPS)

11.3.1 Theoretical Background

11.3.2 Features and Analysis of X-ray Photoelectron Spectra

11.3.3 XPS Investigation of Metal Oxide Nanoparticles and Metal Oxide Colloidal Suspensions

11.3.3.1 Solid–Liquid Interfaces and Nanoparticles in Suspension: Liquid-Jet and Ambient Pressure XPS

11.3.3.2 Valence Band XPS for the Investigation of Oxides

11.3.4 XPS Spectrometer Equipment: Components and Sources

11.3.5 Performing XPS Experiments

11.3.5.1 Planning of the Analysis and Sample Preparation

11.3.6 XPS Qualitative and Quantitative Data Analysis and Fitting

11.4  X-ray Absorption Spectroscopy (XAS)

11.4.1 X-ray Absorption Theory

11.4.2 XAS for the Investigation of Metal Oxide Nanoparticles

11.4.2.1 Materials for Oxygen Evolution Reaction

11.4.2.2 Point Defects and Ferromagnetism

11.4.3 Anatomy of a XAS Beamline

11.4.4 The XAS Experiment: Obtaining Beamtime, Sample Preparation

11.5 Case Studies for the Combined Use of XPS and XAS in Oxide Analysis

11.6 Concluding Remarks: Complementarities and Differences of XPS and XAS

12           Optical Properties: UV/Vis Diffuse Reflectance Spectroscopy and Photoluminescence

Thomas Berger and Anette Trunschke

12.1 Interaction of Metal Oxide Particle-Based Materials with Light

12.2 Spectroscopic Techniques

12.2.1 Transmission Spectroscopy

12.2.2 Diffuse Reflectance Spectroscopy

12.2.2.1 Kubelka–Munk Theory

12.2.2.2 Measurement of Absorption Spectra in Diffuse Reflectance

12.2.2.3 Experimental Constraints and Sources of Error

12.2.2.4 Optical Accessories

12.2.3 Photoluminescence Spectroscopy

12.2.3.1 Principles of Photoluminescence Spectroscopy

12.2.3.2 Inorganic Luminescent Particles

12.2.4 In Situ Cells and Measurement Configurations

12.3 Types of Transitions

12.3.1 UV Region (5.0–2.5 eV)

12.3.1.1 Charge Transfer (CT) Transitions

12.3.1.2 Band-to-Band Transitions

12.3.1.3 Excitonic Surface States in Highly Dispersed Insulating Metal Oxides

12.3.1.4 Organic Ligands and Adsorbates

12.3.2 Visible Region (3.5–1.5 eV)

12.3.2.1 Metal Centered Transitions

12.3.2.2 Localized Surface Plasmon Resonance

12.3.3 Near-Infrared Region (1.5–0.5 nm)

12.3.3.1 Intraband Transitions: Free Carrier Absorption

12.3.3.2 Vibrational Transitions

12.3.3.3 Localized Surface Plasmon Resonance in Degenerately Doped Metal Oxide Semiconductor Nanocrystals

12.4 Case Studies

12.4.1 Heterogeneous Catalysis

12.4.2 Adsorption and Reaction of Porphyrins on Highly Dispersed MgO Nanocube Powders

13 Vibrational Spectroscopies

Christian Hess

13.1 Introduction

13.2 Basic Principles of Vibrational Spectroscopies

13.2.1 IR Spectroscopy

13.2.2 Raman Spectroscopy

13.2.3 Inelastic Neutron Scattering (INS)

13.2.4 In Situ/Operando Characterization

13.3 Vibrational Properties of Metal Oxide Nanoparticles

13.3.1 Structural Identification and Phase Transitions

13.3.2 Particle Size

13.3.3 Strain and Defects

13.3.4 Surface Hydroxyl Groups

13.3.5 Surface Oxygen Species

13.4 Case Study: Ceria Nanoparticles

13.5 Characterization of Metal Oxide Nanoparticles Under Working Conditions

13.6 Conclusions

14           Solid State Magnetic Resonance Spectroscopy of Metal Oxide Nanoparticles

Yamini S. Avadhut and Martin Hartmann

14.1 Introduction

14.2 Basics of Solid-state NMR Spectroscopy

14.2.1 Magic Angle Spinning

14.2.2 Cross-Polarization

14.2.3 Multiple Quantum Magic Angle Spinning

14.3 Selected Examples

14.4 Basics of Electron Paramagnetic Resonance Spectroscopy

14.4.1 The Spin Hamiltonian of Paramagnetic Systems

14.4.2 Defects

14.4.3 Transition Metal Ions

14.5 Selected Example

15           Characterization of Surfaces and Interfaces

Thomas Berger and Oliver Diwald

15.1 Interfaces Determine Stability and Functional Properties: From Manufactured Metal Oxide Nanoparticles to Surface Science Studies

15.2 From Crystal Faces to Nanocrystals: Surface Energetics and Wulff Constructions

15.2.1 Surface Tension, Surface Stress, and Surface Energy

15.2.2 Wulff Construction: A Starting Point for Modelling

15.2.3 Free Energies of Particle Formation and Particle Surfaces

15.3 Changing Interfaces and Microstructures

15.4 The Solid–Vacuum Interface

15.5 Solid–Vapor Interfaces: Thin Water Films as Reactive Environments

15.6 Solid–Liquid Interfaces

15.7 Solid–Solid Interfaces

15.8 Experimental Approaches for Surface and Interface Characterization

15.8.1 Gas Adsorption

15.8.2 He Pycnometry

15.8.3 Nonlinear Optics and Surface Specific Optical Probes

15.8.4 Atomic Force Microscopy (AFM)

15.8.5 Zeta Potential, Ambient Pressure X-ray Photoelectron Spectroscopy (AP-XPS), and Electrochemistry

15.8.6 Surface and Interface Energies

16          Adsorption and Chemical Reactivity

Oliver Diwald and Martin Hartmann

16.1 Introduction

16.2 Some Principles and Key Issues of Adsorption

16.2.1 Physisorption, Chemisorption, and Potential Energy Diagrams

16.2.2 Sticking Probability, Surface Residence Time, and Adsorption Isotherms

16.3 Adsorption in Metal Oxide Nanoparticle Ensembles

16.3.1 Microstructure and Porosity

16.3.2 Adsorption and Diffusion

16.4 Thermal Techniques to Characterize Sorption

16.4.1 Thermogravimetric Analysis (TGA)

16.4.2 Differential Thermal Analysis (DTA)

16.4.3 Differential Scanning Calorimetry (DSC)

16.4.4 Calorimetry

16.5 Temperature-Programmed Techniques

16.5.1 Temperature-Programmed Desorption (TPD)

16.5.2 Temperature-Programmed Reduction (TPR) and Oxidation (TPO)

16.5.3 Temperature-Programmed Surface Reaction (TPSR)

16.6 Adsorption in Liquids – Nanoparticle Dispersions

16.6.1 General Aspects of Adsorption in Solution

16.6.2 Adsorption and Exchange of Ligands at the Colloidal Interface

16.6.3 Grafting of Metal Oxide Nanoparticles with Surfactants

16.7 Nature and Abundance of Catalytically Active Centers

16.8 Probes to Characterize Strength and Activity of Catalytic Sites

16.9 Catalytic Test Reactions

16.9.1 Acidic and Basic Catalysts

16.9.2 Redox Reactions

16.9.3 Bifunctional Catalysis

16.10 Stability and Aging of Metal Oxide Nanoparticles in Catalysis

17           Particle Characterization Technology

Alfred P. Weber

17.1 Introduction

17.2 Sampling and Sample Preparation

17.2.1 Sampling

17.2.2 Sampling from the Gas Phase

17.2.3 Sampling from a Suspension and Sample Preparation

17.3 Image Analysis Techniques

17.3.1 Point operations

17.3.2 Linear Filter

17.3.3 Nonlinear Filter

17.3.4 Morphological Filtering

17.4 Counting Techniques for Single Suspended Nanoparticles

17.4.1 Wide Angle Laser Light Collector

17.4.2 Nano-Laser Doppler Anemometry (NanoLDA)

17.4.3 Condensation Particle Counter (CPC)

17.4.4 Nanoparticle Tracking Analysis (NTA)

17.4.5 Comparison of NTA and Dynamic Light Scattering (DLS)

17.5 Separation Techniques

17.5.1 Field-Flow-Fractionation (FFF)

17.5.2 Analytical Ultracentrifugation

17.5.3 Differential Mobility Analyzer (DMA)

17.5.4 Low Pressure Impactor (LPI)

17.6 Multiparametric Particle Characterization

17.6.1 Aerosol Photoemission Spectroscopy (APES)

17.6.2 Multidimensional NTA on Nanosuspensions

17.6.3 Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)

17.7 Summary

Part V    Characterization of Metal Oxide Nanoparticles with Modelling

18           Atomistic Modeling of Oxide Nanoparticles

Keith McKenna

18.1 Introduction

18.2 Methods

18.2.1 Interatomic Potentials

18.2.2 First Principles Methods

18.2.3 QM/MM (or Embedded Cluster) Methods

18.3 Structure of Nanoparticles

18.3.1 Kinetic vs. Thermodynamic Approaches

18.3.2 0D, 1D, 2D, and 3D Defects in Nanoparticles

18.3.3 Interfaces Between Nanoparticles

18.4 Electronic Properties

18.4.1 Density of States

18.4.2 Ionization Energies and Electron Affinities

18.4.3 Optical Absorption Spectra

18.4.4 Electron Paramagnetic Resonance

18.5 Summary

19           Modeling of Reactions at Oxide Surfaces

Henrik Grönbeck

19.1 Introduction

19.2 Computational Considerations

19.2.1 First Principles Calculations

19.2.2 Ab Initio Thermodynamics

19.2.3 Kinetic Modeling of Surface Reactions

19.3 Some Features of Reactions on Metal Oxide Surfaces

19.4 Adsorbate Pairing

19.4.1 Cooperative Adsorption

19.4.2 Effects of Electronic-Pairing in Modeling of Surface Reactions

19.4.3 Kinetic Modeling of Reactions at Oxide Surfaces

19.4.4 Trans-Ligand Effects

19.5 Reactions at Nanoparticles

19.5.1 Trends in Adsorption Properties

19.6 Conclusions

20           Mesoscale Modelling of Nanoparticle Formation

Eirini Goudeli

20.1 Introduction

20.2 Nanoparticle Characterization

20.2.1 Agglomerate Radii

20.2.2 Fractal Dimension and Mass-Mobility Exponent

20.2.3 Dynamic Shape Factor

20.2.4 Relative Shape Anisotropy

20.3 Coarse-Grained Molecular Dynamics

20.4 Monte Carlo Simulations

20.5 Discrete Element Method

20.5.1 Collision Frequency Function

20.6 Particle Dynamics

20.7 Concluding Remarks

Part IV   Nanoparticles in Biological Environments

21           Biological Activity of Metal Oxide Nanoparticles

Martin Himly, Mark Geppert, and Albert Duschl

21.1 Bio-Nano Interaction

21.2 Interaction of Nanoparticles with Cells

21.2.1 Recognition of Nanoparticles by Cells

21.2.1.1 Uptake of Nanoparticles into Cells

21.2.1.2 Intracellular Fate and Interactions

21.3 Uptake Routes of Nanoparticles into the Body and Their Fate There

21.4 Biological Test Methods for Assessing Biological Activities and Hazards of Nanoparticles

21.4.1 In Vitro Methods

21.4.2 In Vivo Methods

21.4.3 Biological Endpoints

21.5 Exposure of Humans

21.5.1 Intentional Exposure

21.5.2 Unintentional Exposure

21.6 Nanoparticles in the Environment

21.7 Understanding and Regulating Risk

Part VII Case Studies

22           The Properties of Iron Oxide Nanoparticle Pigments

Robin Klupp Taylor

22.1 Introduction

22.2 Properties of Pigments with a Focus on Iron Oxides

22.2.1 Introduction by Way of a Commercial Pigment Example

22.2.2 Colorimetric Properties of Pigment Films

22.2.3 Pigments as Particle Based Optical Materials: General Considerations

22.2.4 Radiative Transfer in a Pigment Film: Kubelka–Munk Theory

22.2.5 Optical Properties of Metal Oxides for Color Pigments

22.2.5.1 Defining the Complex Refractive Index

22.2.5.2 Measuring the Complex Refractive Index

22.2.6 Microscopic Models for Light Scattering

22.2.6.1 Particles Much Smaller Than the Wavelength of Light

22.2.6.2 Spherical Particles Similar in Size or Larger Than the Wavelength of Light (Lorenz–Mie Theory)

22.2.6.3 Simulating Pigment Color Based on Spherical Particles

22.2.6.4 Simulating Pigment Color Based on Nonspherical Particles

23           Zinc Oxide Nanoparticles for Varistors

Oliver Diwald

23.1 Introduction

23.2 Principle of Operation and Microstructure

23.3 Varistor Manufacturing: The Conventional Approach in Industry

23.4 Why Use Synthetic ZnO Nanoparticle Powders as Raw Materials

23.5 Defect Engineering and Electronic Properties

23.6 Impurity Admixture for Microstructure Engineering

23.7 Synthesis of Varistor Nanoparticle Powders

23.8 Formulation and Shaping of ZnO Powders and Dispersions

23.9 Sintering

23.9.1 Alternative Approaches for the Sintering of Nanostructured ZnO Green Bodies

23.10 Cold Sintering and Ceramic–Polymer Composite Varistors

23.11 Concluding Remarks

24           Metal Oxide Nanoparticle-Based Conductometric Gas Sensors

Thomas Berger

24.1 Introduction

24.2 Working Principle of Metal Oxide Particle-Based Conductometric Gas Sensors

24.3 Porous Layers Consisting of Loaded and Doped Metal Oxide Particles

24.3.1 Loaded Metal Oxide Particles

24.3.2 Doped Metal Oxide Particles

24.4 Metal Oxide Nanoparticle-Based Sensing Layers

24.5 Fabrication of Nanoparticle-Based Porous Thick Film Sensing Layers

24.5.1 Layer Deposition Involving Particle Dispersions

24.5.1.1 Synthesis of Sensing Materials

24.5.1.2 Screen Printing

24.5.1.3 Inkjet Printing

24.5.1.4 Drop Coating

24.5.2 Flame Spray Pyrolysis

24.6 Nanostructured Conductometric Gas Sensors for Breath Analysis