Contents
Cover
Half Title page
Title page
Copyright page
Preface
Chapter 1: Electricity
Electric Charge: The Basis of Electricity
Charges at Rest: Electric Field and Electrical Potential
Capacitance and Conductance: The Effects of Electric Fields on Matter
Mobilities: The Movement of Charged Particles in an Electric Field
Electrical Circuits: Models of Electrochemical Behavior
Alternating Electricity: Sine-Waves and Square-Waves
Summary
Chapter 2: Chemistry
Chemical Reactions: Changes in Oxidation State
Gibbs Energy: The Property that Drives Chemical Reactions
Activity: Restlessness in Chemical Species
Ionic Solutions: The Behavior of Dissolved Ions
Ionic Activity Coefficients: The Debye-Hückel Model
Chemical Kinetics: Rates and Mechanisms of Reactions
Summary
Chapter 3: Electrochemical Cells
Equilibrium Cells: Two Electrochemical Equilibria Generate an Interelectrode Voltage
Cells not at Equilibrium: Interchanges of Chemical and Electrical Energy
Cells with Junctions: Two Ionic Solutions Prevented from Mixing
Summary
Chapter 4: Electrosynthesis
Metal Production: Many Metals are Made or Purified Electrolytically
The Chloralkali Industry: A Bounty of Products from Salt and Water
Organic Electrosynthesis: Nylon from Natural Gas
Electrolysis of Water: Key to the Hydrogen Economy?
Selective Membranes: A Quiet Revolution in Small-Scale Inorganic Electrosynthesis
Summary
Chapter 5: Electrochemical Power
Types of Electrochemical Power Source: Primary or Secondary Batteries, Fuel Cells
Battery Characteristics: Quantifying the Properties of Batteries
Primary Batteries: The Leclanché Cell and its Successors
Secondary Batteries: Charge, Discharge, Charge, Discharge, Charge, …
Fuel Cells: Limitless Electrical Energy in Principle, Many Problems in Practice
Summary
Chapter 6: Electrodes
Electrode Potentials: The Reference Electrode is the Key
Standard Electrode Potentials: They are Related to Standard Gibbs Energies
The Nernst Equation: How Activities Influence Electrode Potentials
Electrochemical Series: Elaboration into Pourbaix Diagrams
Working Electrodes: Constructed from Many Materials in Many Shapes and Sizes
Summary
Chapter 7: Electrode Reactions
Faraday’s Law: Necessities for an Electrode Reaction
Kinetics of a Simple Electron Transfer: The Butler-Volmer Equation
Multi-step Electrode Reactions: Studying Kinetics to Elucidate Mechanisms
Summary
Chapter 8: Transport
Flux Density: Solutes in Motion Obey Conservation Laws
Three Transport Modes: Migration, Diffusion and Convection
Migration: Ions Moving in Response to an Electric Field
Diffusion: Fick’s Two Important Laws
Diffusion and Migration: They May Cooperate Or Oppose
Convection: Transport Controlled by Hydrodynamics
Fluxes at Electrodes and in the Bulk: Transport Coefficients
Summary
Chapter 9: Green Electrochemistry
Sensors for Pollution Control: Keeping Watch on Contaminant Levels
Stripping Analysis: Assaying Pollutants in Water at Nanomolar Levels
Electrochemical Purification of Water: Getting the Nasties Out
Electrochemistry of Biological Cells: Nerve Impulses
Summary
Chapter 10: Electrode Polarization
Three Causes of Electrode Polarization: Sign Conventions and Graphs
Ohmic Polarization: Countered by Adding Supporting Electrolyte
Kinetic Polarization: Currents Limited by Electrode Reaction Rates
Transport Polarization: Limiting Currents
Multiple Polarizations: The Big Picture
Polarizations in Two- and Three-Electrode Cells: The Potentiostat
Summary
Chapter 11: Corrosion
Vulnerable Metals: Corrosive Environments
Corrosion Cells: Two Electrodes on the Same Interface
Electrochemical Studies: Corrosion Potential and Corrosion Current
Concentrated Corrosion: Pits and Crevices
Fighting Corrosion: Protection and Passivation
Extreme Corrosion: Stress Cracking, Embrittlement, and Fatigue
Summary
Chapter 12: Steady-State Voltammetry
Features of Voltammetry: Purpose and Classification
Microelectrodes and Macroelectrodes: Size Matters
Steady-State Potential-Step Voltammetry: Reversibility
The Disk Microelectrode: Convenient Experimentally, Awkward to Model
Rotating Disk Voltammetry: A Spinning Disk Electrode without and with a Ring
Shapes of Reversible Voltammograms: Waves, Peaks and Hybrids
Summary
Chapter 13: The Electrode Interface
Double Layers: Three Models of Capacitance
Adsorption: Invasion of the Interface
The Interface in Voltammetry: Nonfaradaic Current, Frumkin Effects
Nucleation and Growth: Bubbles and Crystals
Summary
Chapter 14: Other Interfaces
Semiconductor Electrodes: Capturing the Energy of Light with Photochemistry
Phenomena at Liquid|Liquid Interfaces: Transfers Across “ITIES”
Electrokinetic Phenomena: The Zeta Potential
Summary
Chapter 15: Electrochemistry with Periodic Signals
Nonfaradaic Effects of A.C.: Measuring Conductance and Capacitance
Faradaic Effects of A.C.: Impedance, Harmonics, Rectification
Equivalent Circuits: Deciphering the Impedance
AC Voltammetry: Discriminating Against Capacitive Current
Fourier-Transform Voltammetry: The Harmonic Response to an A.C. Signal
Summary
Chapter 16: Transient Voltammetry
Modeling Transient Voltammetry: Mathematics, Algorithms, or Simulations
Potential-Step Voltammetry: Single, Double and Multiple
Pulse Voltammetries: Normal, Differential and Square
Ramped Potentials: Linear-Scan Voltammetry and Cyclic Voltammetry
Multiple Electron Transfers: The EE Scheme
Chemistry Combined with Electrochemistry: A Plethora of Mechanistic Possibilities
Controlling Current Instead of Potential: Chronopotentiometry
Summary
Appendix
Glossary: Symbols, Abbreviations, Constants, Definitions, and Units
Absolute and Relative Permittivities: Also Some Dipole Moments
Properties of Liquid Water: SI Values at T° and p°
Conductivities and Resistivities: Assorted Charge Carriers
Elements with Major Importance in Electrochemistry: Properties
Transport Properties: Mostly of Ions in Water
Standard Gibbs Energies: Key to Calculating ΔE° and E° Values
Standard Electrode Potentials: Some Examples
Index
This edition first published 2012
© 2012 John Wiley & Sons, Ltd
Reprinted with corrections 2013
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Library of Congress Cataloging-in-Publication Data
Oldham, Keith B.
Electrochemical science and technology: fundamentals and applications / Keith B. Oldham, Jan C. Myland,
Alan M. Bond.
p. cm.
Includes bibliographical references and index.
ISBN 978-0-470-71085-2 (cloth) – ISBN 978-0-470-71084-5 (pbk.) – ISBN 978-1-119-96588-6 (ePDF) –
ISBN 978-1-119-96599-2 (oBook) – ISBN 978-1-119-96684-5 (ePub.) – ISBN 978-1-119-96685-2 (Mobi)
1. Electrochemistry. I. Myland, Jan C. II. Bond, A. M. (Alan Maxwell), 1946- III. Title.
QD553.O42 2011
541’.37–dc23
2011037230
A catalogue record for this book is available from the British Library.
Print ISBN: 9780470710852 (HB)
Print ISBN: 9780470710845 (PB)
Preface
This book is addressed to all who have a need to come to grips with the fundamentals of electrochemistry and to learn about some of its applications. It could serve as a text for a graduate, or senior undergraduate, course in electrochemistry at a university or college, but this is not the book’s sole purpose.
The text treats electrochemistry as a scientific discipline in its own right, not as an offshoot of physical or analytical chemistry. Though the majority of its readers will probably be chemists, the book has been carefully written to serve the needs of scientists and technologists whose background is in a discipline other than chemistry. Electrochemistry is a quantitative science with a strong reliance on mathematics, and this text does not shy away from the mathematical underpinnings of the subject.
To keep the size and cost of the book within reasonable bounds, much of the more tangential material has been relegated to “Webs” – internet documents devoted to a single topic – that are freely accessible from the publisher’s website at www.wiley.com/go/EST. By this device, we have managed largely to avoid the “it can be shown that” statements that frustrate readers of many textbooks. Other Webs house worked solutions to the many problems that you will find as footnotes scattered throughout the pages of Electrochemical Science and Technology. Another innovation is the provision of Excel® spreadsheets to enable the reader to construct accurate cyclic (and other) voltammograms; see Web#1604 and Web#1635 for details.
It was in 1960 that IUPAC (the International Union of Pure and Applied Chemistry) officially adopted the SI system of units, but electrochemists have been reluctant to abandon centimeters, grams and liters. Here, with some concessions to the familiar units of concentration, density and molar mass, we adopt the SI system almost exclusively. IUPAC’s recommendations for symbols are not always adhered to, but (on pages 195 and 196) we explain how our symbols differ from those that you may encounter elsewhere. On the same pages, we also address the thorny issue of signs.
Few references to the original literature will be found in this book, but we frequently refer to monographs and reviews, in which literature citations are given. We recommend Chapter IV of F. Scholz (Ed.), Electroanalytical Methods: guide to experiments and applications 2E, Springer, 2010, for a comprehensive listing of the major textbooks, monographs and journals that serve electrochemistry.
The manuscript has been carefully proofread but, nevertheless, errors and obscurities doubtless remain. If you discover any such anomalies, we would appreciate your bringing it to our attention by emailing Alan.Bond@monash.edu. A list of errata will be maintained on the book’s website, www.wiley.com/go/EST.
Electrochemical Science and Technology: fundamentals and applications has many shortcomings of which we are aware, and doubtless others of which we are ignorant, and for which we apologize. We are pleased to acknowledge the help and support that we have received from Tunde Bond, Steve Feldberg, Hubert Girault, Bob de Levie, Florian Mansfeld, David Rand, members of the Electrochemistry Group at Monash University, the Natural Sciences and Engineering Research Council of Canada, the Australian Research Council, and the staff at Wiley’s Chichester office.
July 2011
Keith B.Oldham
Jan C. Myland
Alan M. Bond