Electrochemistry terminology

Bard, A. J., R. Memming, and B. Miller, Terminology in semiconductor electrochemistry and photoelectrochemical energy conversion, Pure Appl. Chem., 63, 569 (1991). 

The early work in the field of conducting polymers was performed by physicists and hence the terminology employed by them has found its way into electrochemistry. Thus, the films conduct only when they are oxidised, suggesting that conduction is via positive carriers (i.e. holes) and the polymer is termed p-(for positive)-doped, which is merely a descriptive term for the conduction. However, it was quickly realised that if they are to fulfil their full technological potential, a full understanding of the conduction process is essential and this includes determining the identity of the carriers. 

Terminology follows the rales laid down by leading texts of electrochemistry, such as References 7, 8, 14 and 113. 

In this chapter we introduce and discuss a number of concepts that are commonly used in the electrochemical literature and in the remainder of this book. In particular we will illuminate the relation of electrochemical concepts to those used in related disciplines. Electrochemistry has much in common with surface science, which is the study of solid surfaces in contact with a gas phase or, more commonly, with ultra-high vacuum (uhv). A number of surface science techniques has been applied to electrochemical interfaces with great success. Conversely, surface scientists have become attracted to electrochemistry because the electrode charge (or equivalently the potential) is a useful variable which cannot be well controlled for surfaces in uhv. This has led to a laudable attempt to use similar terminologies for these two related sciences, and to introduce the concepts of the absolute scale of electrochemical potentials and the Fermi level of a redox reaction into electrochemistry. Unfortunately, there is some confusion of these terms in the literature, even though they are quite simple. 

The term sonochemistry is used to describe a subject which uses sound energy to affect chemical processes and the terminology is in keeping with that of the longer established methods such as electrochemistry (the use of electricity to achieve chemical activation). These older technologies require some special attribute of the system being activated in order to produce an effect e. g. the use of microwaves (dipolar species), electrochemistry (conducting medium) and photochemistry (the presence of a chromophore) whereas sonochemistry requires only the presence of a liquid to produce its effects. 

The work of Davy was continued and expanded upon by the great English scientist Michael Faraday (1791-1867). Faraday s primary studies in electrochemistry took place between 1833 and 1836. Faraday is responsible for giving us much of our modern electrochemical terminology. The terms electrode, anode, cathode, electrolyte, anion, cation, and electrolysis are all attributed to Faraday. Even more important than his qualitative description of electrochemistry, Faraday did quantitative studies that led to his formulation of electrochemical laws. These laws provided a means to determine the relationship between current and the amount of materials reacting in an electrochemical reaction. Because Faraday s major contributions are still used today, they are covered in the principles of electrochemistry later in the chapter rather than in this historical section. 

Terminology in semiconductor electrochemistry and photo-electrochemical energy conversion , 1991, 63, 569. 

Refs. [i] Denbigh KG (1987) Principles of chemical equilibrium, 4th edn. Cambridge University Press, Cambridge [ii] Robinson RA, Stokes RH (1970) Electrolyte solutions. Butterworths, London [iii] Hamann CH, Hamnett A and Vielstich W (1998) Electrochemistry. Wiley-VCH, Wein-heim [iv] McNaught AD, Wilkinson A (1997) IUPAC Compendium of chemical terminology, 2nd edn. Blackwell Scientific Publ, Oxford [v] http //www.iupac.org/publications/compendium/index.html... 

Refs. [i] (1972) Definition, terminology and symbols in colloid and surface chemistry, Part I. Pure Appl Chem 51 77 [ii] Horanyi G (2002) Specific adsorption. State of art Present knowledge and understanding. In Bard AJ, Stratmann M, Gileadi M, Urbakh M (eds) Thermodynamics and electrified interfaces. Encyclopedia of electrochemistry, vol. 1. Wiley-VCH, Weinheim, pp 349-382 [Hi] Calvo EJ (1986) Fundamentals. The basics of electrode reactions. In Bamford CH, Compton RG (eds) Comprehensive chemical kinetics, vol. 26. Elsevier, Amsterdam, pp 1-78 [iv] Baltruschat H (1999) Differential electrochemical mass spectrometry as a tool for interfacial studies. In Wieckowski A (ed) Interfacial electrochemistry, theory, experiment, and applications. Marcel Dekker, New York, pp 577-597... 

Refs. [i] Christensen PA, Hamnett A (2000) Electrochemical energy conversion. In N Hall (ed) The new chemistry. Cambridge University Press, Cambridge [ii] Hamann CH, Hamnett A, Vielstich W (1998) Electrochemistry. Wiley-VCH, Weinheim [iii] Bard AJ, Stratmann M, Licht S (eds) (2002) Semiconductor electrodes and photoelectrochemistry. Encyclopedia of electrochemistry, vol 6. Wiley-VCH, Weinheim [iv] Bard A], Memming R, Miller B (1991) Terminology in semiconductor electrochemistry andphotoelectrochemical energy conversion, Pure Appl Chem 63 569-596. 

Refs. [i] McNaught AD, Wilkinson A (eds) (1996) IUPAC compendium of chemical terminology (gold book). Blackwell Scientific, Cambridge, p 987 [ii] Bockris JO M, Reddy AKN (2000) Modern electrochemistry, 2nd edn. Springer, Kluwer Acedemic, New York, pp 1808-1810 [iii] Be-senhard JO (1999) Handbook of battery materials. Wiley-VCH, New York, pp 14-15... 

Electrochemical concepts, terminology and symbols are more extensively described in [l.i]. For the field of semiconductor electrochemistry and photoelectrochemical energy conversion see [29] and for corrosion nomenclature [30]. 

Bard, A.J., Memming, R. and Miller, B., Terminology in Semiconductor Electrochemistry and Photoelectrochemical Energy Conversion, Pure Appl. Chem. 63 (1991) 569-596. 

As seen from Equations 1.54-1.56, the intrinsic stability constants of surface reactions are dependent on two factors a chemical and an electric contribution. The chemical contribution is taken into consideration by the mass balance the electric contribution is treated by the charge balance. There are several surface complexation models that mainly differ in the description of the electric double layer that is used to calculate the surface potential, which is done by different double-layer models. These models have been mentioned previously in this chapter. Since, however, the terminology usually used in electrochemistry, colloid chemistry and, especially, in the discussions of surface complexation models is different, they are repeated again ... 

Chemindustry.com Website directory http //www.chemindustry.com/ chem2ask.asp cmd = search id = 0 lUPAC Compendium of Chemical Terminology http //www.chemsoc.org/chembytes/goldbook/index.htm Electrochemistry Resources... 

Use the terminology of electrochemistry (terms such as cell, electrode," cathode," anode")... 

As in all other disciplines, electrochemistry has its own terminology with which one deeds to be familiar before studying specific electrochemical methods. 

In order to set the scene for some of the chapters that follow, it is useful to provide a brief overview of some of the terminology and basic concepts needed to understand electroanalytical techniques. Electrochemistry is a broad field, encompassing those processes that involve the passage of charge across the interface between two... 

From electrochemistry, our discipline has borrowed important terminology. One electrode with electrolyte is called a half-cell to underline that one electrode is not enough. Two electrodes, an electrode pair, are needed to close the electric circuit so that electric current can flow (CC electrodes). A whole cell is two electrodes both submerged in the same electrolyte (e.g., in a glass dish). 

Faraday is responsible for much of the terminology of electrochemistry. Taking the advice of a linguist friend (William Whetwell), he abandoned ideas such as eastode and westode and settled on cathode and anode. 

The new science of electrochemistry to which Faraday had made such important contributions needed a new terminology. Faraday sought the advice of the classical scholar William Whewell (1794-1866), who suggested the terms electrode anode, cathode, ion, anion, cation, electrolyte and electrolysis. The concept of charged particles was still a long way in the future the term ion meant traveller, and thus an anion was a substance that travelled to the anode. 

Though primarily a physicist, Michael Faraday made basic discoveries in electrochemistry, and, with the advice of others, he developed the terminology of this new science. For example, he introduced the terms anode and anion, cathode and cation, electrode, electrolyte, as well as electrolysis. In the 1830 s his invention of a device to measure the quantity of electric current resulted in his discovery of a fundamental law of electrochemistry—that the quantity of electric current that leads to the formation of a certain amount of a particular chemical substance also leads to chemically equivalent amounts of... 

In the following section, several commercial instruments that are useful for electrochemical experiments are shown. In our research laboratory, these instruments have worked well, but they can be substituted for by similar-functioning devices. Sometimes, we provide all the information about the manufacturer and instrument operation. These examples can be extended to the devices of other manufacturers, as the electrochemistry we discuss is independent of the instruments used. Firstly, we define relevant terminology we use in this chapter (Table 5.1). The reader should be familiar with this terminology prior to attempting voltammetry. 

In this section the theory and methodology of electro-analytical chemistry are explored. Chapter 22 provides a (general foundation for the study of subsequent chapters in this section. Terminology- and conventions of electrochemistry as well as theoretical and practical aspects of the measurement of electrochemical potentials and current s are. presented. Chapter 23 comprises the many methods and applications of potentiometry. and constant-potential coulometry and constant-current coulornetrv are discussed in Chapter 2 4. The many facets of the important and widely used technique of voltammetry are presented in ( hapter 2.5. which concludes the section. 

As indicated by the terminology of fuel cells, e.g., PEFC, AFC, SOFC, others (see below), the electrolyte is the decisive cell component, which determines operation temperature, the choice the electrodes (electrocatalytic materials), and finally the specifics of the electrochemistry of the reactants. This, on the other hand, has consequences for the layout of the fuel cell design (balance of plant) and possible applications of the respective fuel cell technology, according to the required duty cycle of the application. 

In humid air, the metal surface will be covered by several monolayers of water as long as no hygroscopic impurities are adsorbed. Under these circumstances, standard electrochemistry will not be valid anymore, as no electrolytic double layer is formed and the reaction products will not be transported away from the surface. Therefore, the rate of any electrochemical reaction will be rather small and the electrode potential , which is measured by the Kel-vinprobe cannot be defined in the usual terminology of electrochemistry but will reflect, e.g., the redox properties of the oxide scale. In particular, the electrode potential ... 

The book is written for people who are already acquainted with the culture and terminology of electrochemistry. However, it can also be read by historians, since it provides a unique source of new information about an important epoch in science history. 

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