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Handbook of Electrochemistry Zsoski Free download

Handbook of Electrochemistry Zsoski

Handbook of Electrochemistry Zsoski Free download

Handbook of Electrochemistry Zsoski

Handbook of Electrochemistry Cynthia G. Zoski
New Mexico State University
Department of Chemistry and Biochemistry
Las Cruces, New Mexico, USA

Electrochemistry now plays an important role in a vast number of fundamental research and applied areas. These include, but are not limited to, the exploration of new inorganic and organic compounds, biochemical and biological systems, corrosion, energy applications involving fuel cells and solar cells, and nanoscale investigations. There are many excellent textbooks and monographs, which explain the fundamentals and theory of electrochemistry. This handbook is not a textbook, however, but rather a source of electrochemical
information, details of experimental considerations, representative calculations, and illustrations of the possibilities available in electrochemical experimentation. It is most closely allied with the textbook Electrochemical Methods: Fundamentals and Applications by Allen J. Bard and Larry R. Faulkner, second edition

The Handbook of Electrochemistry is divided into five parts: Fundamentals (Chapter 1), Laboratory Practical (Chapters 2–10), Techniques (Chapters 11–14), Applications (Chapters 15–17), and Data (Chapters 18–20). Chapter 1 covers the fundamentals of electrochemistry that are essential for everyone working in this field and sets the stage for the following 19 chapters. Thus, Chapter 1 presents an overview of electrochemical conventions, terminology, fundamental equations, electrochemical cells, experiments, literature, textbooks, and specialized books. Laboratory aspects of electrochemistry are emphasized in the following nine chapters that include Practical Electrochemical Cells (Chapter 2), Solvents and Supporting
Electrolytes (Chapter 3), Reference Electrodes (Chapter 4), Solid Electrode Materials: Pretreatment and Activation (Chapter 5), Ultramicroelectrodes (Chapter 6), Potentiometric Ion-Selective Electrodes (Chapter 7), Chemically Modified Electrodes (Chapter 8),Semiconductor Electrodes (Chapter 9), and  icroelectrode Arrays (Chapter 10). Electrochemical techniques covered in this handbook range from classical experiments
(Chapter 11) to Scanning Electrochemical Microscopy (SECM) (Chapter 12), Electrogenerated Chemiluminesence (Chapter 13), and Spectroelectrochemistry (Chapter 14). These four chapters also include representative applications based on the method described.Specific electrochemical applications based on the preceding chapters illustrate the impact of electrochemistry in exploring diverse topics ranging from electrode kinetic determinations (Chapter 15), unique aspects of metal deposition (Chapter 16) including micro- and nanostructures, template deposition, and single particle deposition, and electrochemistry in small places and at novel interfaces (Chapter 17) including biological cells, single molecule
eletrochemistry, and electrochemistry at liquid/liquid interfaces. The remaining three chapters provide useful electrochemical data and information involving electrode potentials (Chapter 18), diffusion coefficients (Chapter 19), and methods used in measuring liquidjunction potentials (Chapter 20). The majority of the chapters were supervised by a single corresponding author. Exceptions to this are Chapters 6, Ultramicroelectrodes; Chapter 16, Metal Deposition; and Chapter 17, Electrochemistry in Small Places and at Novel Interfaces, where several authors contributed to different sections in a specific chapter I would like to thank the contributors of this handbook, colleagues in the electrochemical community, and the authors of the many papers, textbooks, and specialized books whose work is cited in this handbook and has led to the development of electrochemistry,its expansion into diverse areas, and much of the information presented in this handbook.I especially want to thank Allen J. Bard, a pioneer in electrochemistry, for his helpful comments, suggestions, advice, and unwavering encouragement during the editing of this handbook.
Contents
Preface
Corresponding Authors
I Fundamentals
1 Fundamentals
1.1 Conventions in Electrochemistry
1.1.1 Potential conventions
1.1.2 Current conventions
1.2 Terminology.
1.3 Fundamental Equations
1.3.1 Nernst equation
1.3.2 Equilibrium constant 
1.3.3 Mass-transfer limited current
1.3.4 Cottrell equation .
1.3.5 Faraday’s law . . 
1.4 Factors Affecting Reaction Rate and Current .
1.4.1 Current, current density, and rate. . . . . . . . 
1.4.2 Reversibility . . . . . . . . . . . . . . . . . . . . . . . 
1.4.3 Kinetics. . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5 Equations Governing Modes of Mass Transfer
1.5.1 Nernst–Planck equation. . . . . . . . . . . . . . . 
1.5.2 Fick’s laws of diffusion . . . . . . . . . . . . . . . 
1.6 Electrochemical Cells. . . . . . . . . . . . . . . . . . 
1.7 Cell Resistance; Capacitance; Uncompensated Resistance 
1.8 Overview of Electrochemical Experiments . . . . . . . . . . . . 
1.9 Electrochemistry Literature; Textbooks; Specialized Books
1.9.1 Electrochemical journals . . . . . . . . . . . . . . . . . . . . . . . . 
1.9.2 Specialized texts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.9.3 Review series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
II Laboratory Practical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
2 Practical Electrochemical Cells . . . . . . . . . . . . . . . . . . . . . .
2.1 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
2.2 General Cell Designs . . . . . . . . . . . . . . . . . . . . . . . . . . . 
2.2.1 Two-electrode cells . . . . . . . . . . . . . . . . . . . . . . . . . . 
2.2.2 Three-electrode cells . . . . . . . . . . . . . . . . . . . . . . . . . 
2.3 Electrochemical Cells for Specific Applications . . . . . . . 
2.3.1 Flow-through cells . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.2 Thin-layer cells (TLCs) . . . . . . . . . . . . . . . . . . . . . . . 
2.3.3 Spectroelectrochemical cells . . . . . . . . . . . . . . . . . . . 
2.3.4 Electrochemical cells for molten salts . . . . . . . . . . . . . 
2.3.5 Attachment to a vacuum line . . . . . . . . . . . . . . . . . . . 
2.4 Establishing and Maintaining an Inert Atmosphere. . . . . 
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
3 Solvents and Supporting Electrolytes . . . . . . . . . . . . . . . 
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
3.2 Electrolyte Conductivity. . . . . . . . . . . . . . . . . . . . . . . .
3.3 Cells, Electrodes and Electrolytes. . . . . . . . . . . . . . . . 
3.4 Cell Time Constants . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5 Solvents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.1 Protic solvents. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.2 Nitriles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.3 Halogenated organics . . . . . . . . . . . . . . . . . . . . . . .
3.5.4 Amides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
3.5.5 Sulfoxides and sulfones. . . . . . . . . . . . . . . . . . . . . .
3.5.6 Ethers, carbonates, lactone . . . . . . . . . . . . . . . . . . 
3.6 Salts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
3.7 “Exotic” Electrolytes . . . . . . . . . . . . . . . . . . . . . . . . 
3.8 Purification Procedures for some Commonly Used Solvents in Electrochemistry
3.8.1 Acetonitrile
3.8.2 Butyronitrile
3.8.3 Benzonitrile
3.8.4 Propylene carbonate
3.8.5 Dichloromethane
3.8.6 Dimethylformamide
3.9 Purification Procedures for some Commonly Used Salts in Electrochemistry
3.9.1 Tetraethylammonium tetrafluoroborate . . . . .
3.9.2 Tetraethylammonium tetraphenylborate. . . . .
3.9.3 Tetraethylammonium hexafluorophosphate . .
3.9.4 Tetrabutylammonium tetrafluoroborate . . . . .
3.9.5 Tetrabutylammonium hexafluorophosphate . .
3.9.6 Lithium perchlorate. . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Reference Electrodes . . . . . . . . . . . . . . . . . . . . 
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . 
4.1.1 Selecting a reference electrode . . . . . . . .
4.1.2 Converting between aqueous potential scales
4.2 Basic Components of a Reference Electrode . 
4.2.1 Body material . . . . . . . . . . . . . . . . . . . . . . .
4.2.2 Top seal . . . . . . . . . . . . . . . . . . . . . . . . . . .
viii Contents
4.2.3 Junction (4) . . . . . . . . . . . . . . . . . . . . . . . . 
4.2.4 Active component of RE . . . . . . . . . . . . . . 
4.3 Electrode Details and Fabrication . . . . . . . . . 
4.3.1 Hydrogen electrodes . . . . . . . . . . . . . . . . . 
4.3.2 Mercury electrodes (24) . . . . . . . . . . . . . . 
4.3.3 Silver electrodes . . . . . . . . . . . . . . . . . . . . 
4.3.4 Quasi-reference electrodes (QRE) . . . . . . .
4.4 Junctions . . . . . . . . . . . . . . . . . . . . . . . . . . . 
4.4.1 Filling solutions . . . . . . . . . . . . . . . . . . . . . 
4.4.2 Salt bridges . . . . . . . . . . . . . . . . . . . . . . . .
4.4.3 Double-junction reference electrodes. . . . . 
4.4.4 Reference electrode impedance . . . . . . . . .
4.5 Reference Electrodes: Nonaqueous Solvents 
4.6 Reference Electrode Calibration . . . . . . . . . .
4.6.1 Versus a second reference electrode. . . . . 
4.6.2 Using a well-defined redox couple . . . . . . 
4.7 Maintenance. . 
4.7.1 Storage . . . .
4.7.2 Cleaning junctions
4.7.3 Replacing filling solutions
4.7.4 Regenerating the reference electrode
4.8 Troubleshooting 
4.8.1 Special notes
References
5 Solid Electrode Materials: Pretreatment and Activation
5.1 Introduction
5.2 Carbon Electrodes
5.2.1 Highly oriented pyrolytic graphite
5.2.2 Glassy carbon
5.2.3 Pyrolyzed photoresist films (PPF)
5.2.4 Carbon fibers
5.2.5 Carbon nanotubes
5.2.6 Diamond films
5.2.7 Tetrahedral amorphous carbon (Ta-C) films
5.3 Metal Electrodes
5.3.1 Polycrystalline platinum and gold 
5.3.2 Single-crystal platinum and gold
5.4 Semiconductor Electrodes
5.4.1 Indium tin oxide (ITO)
5.5 Conclusions
Acknowledgments
References
6 Ultramicroelectrodes
6.1 Behavior Of Ultramicroelectrodes
Contents ix
6.1.1 Electrode response times
6.1.2 Factors that influence the electrode response time
6.1.3 Origins of non-ideal responses 
6.1.4 Fundamentals of faradaic electrochemistry
6.1.5 Origins of non-ideal faradaic responses
References
6.2 Microelectrode Applications
6.2.1 Electroanalysis at the micro-and nano-length scale
6.2.2 Spatially heterogeneous systems: biological structures
6.2.3 Low conductivity media
6.2.4 Ultrafast electrochemical techniques
6.2.5 AC electrokinetics
References
6.3 UME Fabrication/Characterization Basics
6.3.1 Platinum and gold inlaid disks 5 m diameter
References 
6.3.3 Laser-pulled ultramicroelectrodes
References
6.3.4 Platinum conical ultramicroelectrodes
6.3.5 Flame-etched carbon nanofibers
6.3.6 Electrochemically etched carbon fiber electrodes
6.3.7 Gold spherical microelectrodes
6.3.8 Hg microhemispherical electrodes
6.3.9 Clarke oxygen microelectrode
6.3.10 Nitric oxide microsensors
6.3.11 Glass nanopore electrodes
7 Potentiometric Ion-Selective Electrodes
7.1 Introduction
7.2 Classification and Mechanism
7.2.1 Phase boundary potential
7.2.2 Ion-exchanger-based ISEs
7.2.3 Neutral-ionophore-based ISEs
7.2.4 Charged-ionophore-based ISEs
x Contents
7.3 Equilibrium Potentiometric Responses
7.3.1 The Nikolsky–Eisenman equation and phase boundary potential model
7.3.2 Effect of ionic sites on selectivity
7.3.3 Apparently “non-Nernstian” equilibrium responses
7.4 Non-Equilibrium Potentiometric Responses
7.4.1 Mixed ion-transfer potentials
7.4.2 Elimination of non-equilibrium effects in separate solutions
7.4.3 Effects of transmembrane ion flux on detection limit
7.4.4 Non-equilibrium responses for polyion detection
7.5 Conclusions
References
8 Chemically Modified Electrodes
8.1 Introduction
8.2 Substrate Materials and Preparation
8.3 Modified Electrode Types
8.3.1 Langmuir-Blodgett
8.3.2 Self-assembly
8.3.3 Covalent attachment
8.3.4 Clay modified electrodes
8.3.5 Zeolite modified electrodes
8.3.6 Sol-gel modified electrodes
8.3.7 Polymer modified electrodes
8.3.8 DNA modified electrodes
8.4 Conclusions and Prospects
References
9 Semiconductor Electrodes
9.1 Introduction
9.2 Semiconductor Basics
9.2.1 Band theory of solids
9.2.2 Size quantization in semiconductors
9.3 Energetics of a Semiconductor
9.3.1 Semiconductor–electrolyte interface (SEI)
9.4 Semiconductor Electrodes
9.4.1 Electron transfer at semiconductor–electrolyte interface
9.4.2 lluminated semiconductor electrodes
9.4.3 Cyclic voltammetry (CV) at semiconductor electrodes
9.4.4 Fermi-level pinning in semiconductor electrodes
9.4.5 Characterization of the SEI by scanning electrochemical
microscopy (SECM)
9.5 Types of Semiconductor Electrodes
9.5.1 Single crystal and epitaxial film electrodes
9.5.2 Polycrystalline electrodes
Contents xi
9.6 Nanostructured Semiconductor Electrodes (NSSE)
9.6.1 Epitaxial methods for the preparation of NSSE
9.6.2 Preparation of particulate films
9.6.3 Electrochemistry on nanostructured semiconductors
9.6.4 Electrochemistry on suspended semiconductor nanoparticles
9.7 Semiconductor Electrode Applications
9.7.1 Solar cells
9.7.2 Sensors
10 Microelectrode Arrays
10.1 Introduction
10.2 Classification of Microelectrode Arrays
10.2.1 Microelectrode designs
10.2.2 Microelectrode array behavior
10.3 Theory: Diffusion at Microelectrode Arrays
10.3.1 Arrays of electrodes operating at identical potentials
10.3.2 Arrays of electrodes operating in generator/collector mode
10.4 Fabrication of Microelectrode Arrays
10.4.1 Mechanical methods
10.4.2 Template approaches
10.4.3 Lithographic techniques
10.4.4 Etching techniques
10.5 Electrochemical Characterisation of Microelectrode Arrays
10.5.1 Chronoamperometry and cyclic voltammetry
10.5.2 Scanning electrochemical microscopy
10.5.3 Optical microscopy
10.6 Conclusion and Prospects
III Techniques
11 Classical Experiments
11.1 Introduction
11.2 Selected Experimental Techniques
11.2.1 Potential steps
11.2.2 Potential sweeps. . . . . . . . . . . . . . . . 
11.2.3 Combinations of sweeps and steps
11.2.4 Microelectrodes
11.2.5 Rotating disc electrodes
11.2.6 Small amplitude perturbations and impedance methods
11.3 Simulations
11.3.1 Electrochemical simulations—a few questions
11.3.2 Basic principles of an electrochemical simulation
xii Contents
11.4 Troubleshooting Electrochemical Experiments: A Checklist
11.4.1 Checking the results
11.4.2 No current response
11.4.3 Potential shift
11.4.4 Currents lower than expected
11.4.5 Slanted voltammogram
11.4.6 Noisy current
11.4.7 Other common problems
12 Scanning Electrochemical Microscopy
12.1 Introduction and Principles
12.2 Instrumentation
12.2.1 Basic SECM apparatus
12.2.2 Combining SECM with other techniques
12.3 Methods and Operational Modes
12.3.1 Amperometric methods
12.3.2 Potentiometric method
12.3.3 Imaging
12.4 Applications
12.4.1 Heterogeneous kinetics
12.4.2 Homogeneous chemical reactions
12.4.3 Catalytic activity
12.4.4 Surface reactivity
12.4.5 Patterning
13 Electrogenerated Chemiluminescence
13.1 Concepts and History
13.2 Types of Luminescence
13.3 Fundamental Reactions
13.3.1 Ion annihilation ECL
13.3.2 Coreactant ECL (123)
13.4 Experimental Setup
13.4.1 Electrochemical media
13.4.2 Cell design and electrodes
13.4.3 Light detection and ECL instrumentation
13.5 Types of Experiments
13.5.1 Ion annihilation ECL: Ru(bpy)3 2+ and derivatives
13.5.2 Coreactant ECL of Ru(bpy)3
2+/TPrA system in aqueous solutions
13.6 Applications
13.6.1 Applications of Ru(bpy)3
2+ ECL: determination of oxalate and organic acids
13.6.2 Applications of Ru(bpy)3 2+ ECL: determination of amines
Contents xiii
13.6.3 Applications of Ru(bpy)3
2+ ECL: determination of amino acids
13.6.4 Applications of Ru(bpy)3
2+ ECL: determination of pharmaceuticals
13.6.5 Applications of Ru(bpy)3 2+ ECL: determination of Ru(bpy)32+
13.6.6 Applications of Ru(bpy)3
2+ ECL in capillary electrophoresis (CE)
and micro-total analysis ( TAS)
13.6.7 Application of Ru(bpy)3
2+ ECL: determination of clinical analytes
13.6.8 Applications of Ru(bpy)3
2+ ECL: analytes associated with food, water, and biological agents
References
14 Spectroelectrochemistry .
14.1 Introduction . . . . . . . . 
14.2 Light Transmission and Reflection at an Electrode Surface
14.3 Electronic Spectroscopy
14.3.1 Transmittance spectroscopy and optically transparent cell materials
14.3.2 Thin layer spectroelectrochemistry
14.3.3 Spectroelectrochemistry: semi-infinite linear diffusion .
14.3.4 Long optical pathway thin layer cells (LOPTLC) . . . .
14.3.5 Reflectance spectroscopy . . . . . . . . . . . . . . . . . . . . .
14.4 Luminiscence Spectroelectrochemistry . . . . . . . . . . . . .
14.4.1 Steady-state luminescence spectroelectrochemistry . .
14.4.2 Time-resolved luminescence spectroelectrochemistry 
14.5 Vibrational Spectroelectrochemistry .
14.5.1 IR spectroelectrochemistry . . . . . . 
14.5.2 Raman spectroelectrochemistry . . .
14.6 Outlook . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . .
IV Applications . . . . . . . . . . . . . . . . . . . . 
15 Determination of Electrode Kinetics . . .
15.1 Introduction to Kinetic Measurements
15.2 Heterogeneous Electron Transfer: Transient Methods
15.2.1 Linear sweep and cyclic voltammetry
15.2.2 Sampled-current voltammetry
15.2.3 Ac voltammetry
15.3 Heterogeneous Electron Transfer: Steady-State Methods. 
15.3.1 Steady-state voltammetry . . . . . . . . . . . . . . . .
15.3.2 Scanning electrochemical microscopy (SECM)
15.4 Processes with Coupled Homogeneous Reactions
15.4.1 Linear sweep and cyclic voltammetry
15.4.2 Scanning electrochemical microscopy (SECM)
15.4.3 Simulations and curve fitting
xiv Contents
16 Metal Deposition
16.1 Electrodeposition of Nanostructures and Microstructures on Highly
Oriented Pyrolytic Graphite (HOPG)
16.1.1 Introduction and perspective
16.1.2 HOPG: seeing electrodeposited metal nano- and microparticles
16.1.3 Brownian Dynamics simulations: understanding particle size distribution broadening
16.1.4 “Slow-growth” electrodeposition: dimensionally uniform metal nano- and microparticles
16.1.5 Electrodeposition of metal nanowires
16.2 Template Deposition of Metals
16.2.1 Introduction
16.2.2 Templating membranes
16.2.3 Template deposition of metals
16.2.4 Morphological and optical properties
16.2.5 Electrochemistry with template nanomaterials: nanoelectrode ensembles
16.2.6 Conclusions and prospects
16.3 Single Particle Deposition on Nanometer Electrodes
16.3.1 Introduction
16.3.2 Electrode selection
16.3.3 Electrodeposition of particles: electrokinetic vs. diffusion control
16.3.4 Nucleation exclusion zones: modeling particle growth
16.3.5 Examples of systems
17 Electrochemistry in Small Places and at Novel Interfaces
17.1 Electrochemistry in and at Single Biological Cells
17.1.1 Electrochemistry at the cell membrane–solution interface
17.1.2 Electrochemistry at lipid bilayer membranes
17.1.3 Electrochemistry in small drops and vials
17.1.4 Intracellular electrochemistry
17.1.5 Conclusions
17.2 Single Molecule Electrochemistry
17.2.1 Introduction
17.2.2 Special topics
17.2.3 Conclusions
17.3 Electrochemistry at Liquid/Liquid Interfaces
17.3.1 Introduction
17.3.2 Fundamentals
17.3.3 Charge transfer reactions at liquid/liquid interfaces
17.3.4 Methodologies and techniques
Contents xv
17.3.5 Applications
17.3.6 Prospects
18 Electrode Potentials
18.1 Overview
18.2 Estimated Potential Ranges: Aqueous and Non-aqueous Solutions
18.3 Standard Electrode Potentials: Aqueous Solutions
18.4 Formal Electrode Potentials: Aprotic Solvents
18.5 Formal Electrode Potentials: Common Organic Mediators
18.6 Electrode Potentials: Inorganic One-Electron Complexes
18.7 Formal Electrode Potentials: Biological Redox Species
18.8 Formal Electrode Potentials: Common Vitamins, Drugs, Neurochemicals
18.9 Abbreviations
18.10 Chemical Structures
19 Diffusion Coefficients
19.1 Introduction
19.2 Fundamental Equations
19.3 General Considerations
19.3.1 Selection of a technique
19.3.2 Electrode
19.3.3 Electrochemical system
19.3.4 Instrumentation
19.4 Electrochemical Methods
19.4.1 Potential step techniques (chronoamperometry)
19.4.2 Rotating disk electrode techniques
19.4.3 Potential sweep techniques
19.4.4 Current step techniques (chronopotentiometry)
19.4.5 Scanning electrochemical microscopy (SECM) techniques
19.5 Tables of Diffusion Coefficients
20 Liquid Junction Potentials
20.1 Types of Liquid Junctions
20.1.1 Interfacial potentials without electrolyte transport
20.1.2 Interfacial potentials with electrolyte transport
20.2 Transference Numbers and Conductivity
20.2.1 Experimental methods of determining transference number
20.2.2 Sample calculations of ionic transference numbers
20.2.3 Experimental methods of determining electrolytic conductivity
20.2.4 Sample calculations relating to electrolytic conductivity
20.2.5 Tabulation of parameters related to electrolyte conductance
20.3 Minimization of Liquid Junction Potentials
20.3.1 Balancing ionic mobilities
20.3.2 The salt bridge
20.4 Junctions of Immiscible Liquids
20.4.1 The non-polarisable liquid/liquid interface
20.4.2 The polarisable liquid/liquid interface
20.5 Non-Classical Electrolytes: Polymer–Based Electrolytes and Ionic Liquids
References

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