Solid-state electrochemistry thermodynamics

J. Maier, Solid state electrochemistry I Thermodynamics and kinetics of charge carriers in solids, in Modern Aspects of Electrochemistry Vol. 38, Ed. by B. E. Conway, C. G. Vayenas, R. E. White, and M. E. Gamboa-Adelco Kluwer Academic/Plenum Pubishers, New York, 2005, pp. 1-173. 

Solid State Electrochemistry I Thermodynamics and Kinetics of Charge Carriers in Solids... 

Girdauskaite, E., llllmann, H., Al Daroukh, M., Vashook, V., Billow, M., and Guth, U. 2007. Oxygen stoichoimetry, unit cell volumes, and thermodynamic quantities of perovskite-type oxides. Journal of Solid State Electrochemistry 11, 469-477. 

The opening chapter of this Handbook highlights the characteristic features of solid-state electrochemistry, including basic phenomena, measurement techniques, and key apphcations. Materials research strategies that are based on electrochemical insight and the potential of nanostructuring are detailed in particular. Fundamental relationships between the decisive thermodynamic and kinetic parameters governing electrochemical processes are also briefly discussed. 

Solid-state electrochemistry is an important and rapidly developing scientific field that integrates many aspects of classical electrochemical science and engineering, materials science, solid-state chemistry and physics, heterogeneous catalysis, and other areas of physical chemistry. This field comprises - but is not limited to - the electrochemistry of solid materials, the thermodynamics and kinetics of electrochemical reactions involving at least one solid phase, and also the transport of ions and electrons in solids and interactions between solid, liquid and/or gaseous phases, whenever these processes are essentially determined by the properties of solids and are relevant to the electrochemical reactions. The range of applications includes many types of batteries and fuel cells, a variety of sensors and analytical appliances, electrochemical pumps and compressors, ceramic membranes with ionic or mixed ionic-electronic conductivity, solid-state electrolyzers and electrocatalytic reactors, the synthesis of new materials with improved properties and corrosion protection, supercapacitors, and electrochromic and memory devices. 

McBreen comprehensively reviewed nickel hydroxide battery electrodes, the solid state chemistry of nickel hydroxides, and the electrochemical reactions of the Ni(OH)21 NiOOH couple. Any critical discussion of the thermodynamic data of nickel oxide hydroxides with higher oxidation states has to refer to this splendidly written account of nickel solid state electrochemistry. 

The principles behind this membrane technology originate from solid-state electrochemistry. Conventional electrochemical halfceU reactions can be written for chemical processes occurring on each respective membrane surface. Since the general chemistry under discussion here is thermodynamically downhill, one might view these devices as short-circuited solid oxide fuel cells (SOFCs), although the ceramics used for oxygen transport are often quite different. SOFCs most frequently use fluorite-based solid electrolytes - often yttria stabUized zirco-nia (YSZ) and sometimes ceria. In comparison, dense ceramics for membrane applications most often possess a perovskite-related lattice. The key fundamental... 

We discuss the similarities and differences between Kquid-state electrochemistry (LSE) and solid-state electrochemistry (SSE). Although based on the same thermodynamic principles, the properties of these cells are quite distinct. Differences exist in the bulk conduction mechanism, partially in electrode reaction and in cell construction and morphology. This also leads to differences in appKcations. 

LSE, the classical electrochemistry, is concerned with electrochemical cells (ECs) based on liquid ionic-conductors (liquid electrolytes (LEs)). Solid-state electrochemistry is concerned with ECs in which the ionic conductor (electrolyte) is a solid. Both fields are based on common thermodynamic principles. Yet, the finer characteristics of ECs in the two fields are different because of differences in the materials properties, conduction mechanisms, morphology and cell geometry. Differences that come immediately to mind are (1) The lack of electronic (electron/hole) conduction in most LEs, while electronic conduction exists to some extent in all solid electrolytes (SEs). (2) In LEs both cations and anions are mobile, while in SEs only one kind of ions is usually mobile while the other forms a rigid sublattice serving as a frame for the motion of the mobile ion. An... 

The field of solid-state electrochemistry—the electrochemistry of solids— has developed rapidly since about the middle of the twentieth century. This was caused by the discovery of new solid elecfiolytes with high ionic conductivity and some fundamental publications which pointed out the importance of solid ionic conductors for the thermodynamic investigations. 

Adhesion and Adhesives Adsorption Auger Electron Spectroscopy Bonding and Structure IN Solids Catalysis, Industrial Catalyst Characterization Chemical Thermodynamics Crystallography Photochemistry, Molecular Photoelectron Spectroscopy Solid-State Electrochemistry Tribology... 

An electrode which is reversible to electrons but irreversible to ions is a common situation in both aqueous and solid state electrochemistry. For determinations of ionic conductivity in electrolytes, this type of electrode has proved useful, because the concentrations of majority ionic species do not depend critically on the imposition of a well-defined thermodynamic activity of the electroactive neutral species. Measurements with two irreversible electrodes of a nonreactive metal are then permissible numerous examples are found in the solid-electrolyte literature. Minority electronic transport however, typically depends very strongly on the activity of neutral components, and care must be taken to utilize thermodynamically meaningful experiments to determine minority conductivities. Asymmetric cells using one reversible electrode and one irreversible electrode are then appropriate, but have actually been little explored using ac impedance methods. 

Micro-scale solid-state electrochemistry is ideally suited to the parallel determination of high-temperature thermodynamic properties of transuranium oxides. The UO2+,-MO systems (M denotes alkaline earth) have been thoroughly investigated (Fujino 1988). Solid-state electrochemistry of transuranium oxides have been reported only for Pu02 and (U, Pu)02+x as reviewed in Anon (1967). 

Such a Fermi level shift can result in effects which can easily be confused with capacitive effects . These effects are called by the electrochemists, pseudo-capacitive effects. In solid state electrochemistry they are sometimes also described as an adsorption with partial transfer. To illustrate the point, let us consider the schematic situation depicted in Fig.6, It is familiar to electrochemists. Without entering into the details of the relevant surface levels and densities, we can say, from a thermodynamical viewpoint, that the electrode measures the chemical activity of 0 atoms in a perturbed layer located at the phase boundary. The electrode potential variations are related to the 0-chemical-activity-variations by formula (22). Extending the hypotheses, here, the 0 atoms are supposed to be soluble in the electronic conductor but the direct exchange of oxide ions is regarded as impossible. 

Solid state electrochemistry is concerned with all kinds of electrical phenomena associated with chemical changes, and vice versa, in solid state. These are induced by migration of charged mass particles or ions under the action of a variety of thermodynamic forces, gradients of component chemical potentials, electrical potential, temperature, stress, and the like. Naturally the solids composed of ions, viz., ionic solid compounds serve the main stages for solid state electrochemistry, hi solid state, electrons may also be mobile, which makes solid state electrochemistry even more versatile and interesting. 

An ionic compound, e.g., MO, consists of charged compruients, cations (M ), anions (O ) and electrons (e ). These charged components are rendered mobile only via defects. It is thus a prerequisite in solid state electrochemistry to understand the defect structure of the system of interest, that is, types of defects and their concentrations against the thermodynamic variables of the system. 

Solid Oxide Fuel Cells, Thermodynamics Solid State Electrochemistry, Electrochemistry Using Solid Electrolytes... 

E. Girdauskaite, H. Ullmann, M. Al Daroukh, et al.. Oxygen Stoichiometry, Unit Cell Volume, and Thermodynamic Quantities of Perovskite-type Oxides, Journal of Solid State Electrochemistry, 11, 469-477 (2007). 

Interface and colloid science has a very wide scope and depends on many branches of the physical sciences, including thermodynamics, kinetics, electrolyte and electrochemistry, and solid state chemistry. Throughout, this book explores one fundamental mechanism, the interaction of solutes with solid surfaces (adsorption and desorption). This interaction is characterized in terms of the chemical and physical properties of water, the solute, and the sorbent. Two basic processes in the reaction of solutes with natural surfaces are 1) the formation of coordinative bonds (surface complexation), and 2) hydrophobic adsorption, driven by the incompatibility of the nonpolar compounds with water (and not by the attraction of the compounds to the particulate surface). Both processes need to be understood to explain many processes in natural systems and to derive rate laws for geochemical processes. 

J. Koi3fta, Principles of Electrochemistry, Wiley, New York, 1987 J. Goodisman, Electrochemistry Theoretical Foundations, Quantum and Statistical Mechanics, Thermodynamics, the Solid State, Wiley, New York, 1987 G. Battistuzzi, M. Bellei, and M. Sola, J. Biol. Inorganic Chem. 11, 586-592 (2006) R. Heyrovska, Electroanalysis, 18, 351-361 (2006) G. Battistuzzi, M. Borsari, G. W. Ranters, E. de Waal, A. Leonard , and M. Sola, Biochemistry 41, 14293-14298 (2002). 

Refs. [i] Inzelt G (2005) / Solid State Electrochem 9 245 [ii] Horanyi G (1980) Electrochim Acta 25 45 [iii] Horanyi G (2004) In Horanyi G (ed) Radiotracer studies of interfaces. Elsevier, Amsterdam, chapters 1,2,4,6 [iv] Horanyi G (2002) State of art present knowledge and understanding. In Bard AJ, Stratmann M, Gileadi E, Urbakh M (eds) Thermodynamics and electrified interfaces. Encyclopedia of electrochemistry, vol. 1. Wiley-VCH, Weinheim, Chap. 3 [v] Horanyi G (1999) Radiotracer studies of adsorption/sorption phenomena at electrode surfaces. In Wieckowski A (ed) Interfacial electrochemistry. Marcel Dekker, New York, pp 477 [vi] Horanyi G, Inzelt G (1978) / Electroanal Chem 87 423 [vii] Horanyi G, Inzelt G, Szetey E (1977) / Electroanal Chem 81 395 [viii] Vertes G, Horanyi G (1974) / Electroanal Chem 52 47 [ix] Horanyi G (1994) Catal Today19 285 [x] Horanyi G (2003) Electrocatalysis - heterogeneous. In Horvath IT (ed) Encyclopedia of catalysis, vol. 3. Wiley Interscience, Hoboken, pp 115-155 [xi] Inzelt G, Horanyi G (2006) The nickel group (nickel, palladium, and platinum). In Bard AJ, Stratmann M, Scholz F, Pickett CJ (eds) Inorganic chemistry. Encyclopedia of electrochemistry, vol 7a. Wiley-VCH, Weinheim, chap. 18... 

In the first part of this century, electrochemical research was mainly devoted to the mercury electrode in an aqueous electrolyte solution. A mercury electrode has a number of advantageous properties for electrochemical research its surface can be kept clean, it has a large overpotential for hydrogen evolution and both the interfacial tension and capacitance can be measured. In his famous review [1], D. C. Grahame made the firm statement that Nearly everything one desires to know about the electrical double layer is ascertainable with mercury surfaces if it is ascertainable at all. At that time, electrochemistry was a self-contained field with a natural basis in thermodynamics and chemical kinetics. Meanwhile, the development of quantum mechanics led to considerable progress in solid-state physics and, later, to the understanding of electrostatic and electrodynamic phenomena at metal and semiconductor interfaces. 

The electrochemistry of solids is of great current interest to research and development. The technical applications include batteries with solid electrolytes, high-tempe-rature fuel cells, sensors for measuring partial pressures or activities, display units and, more recently, the growing field of chemotronic components. The science and technology of solid state electrolytes is sometimes called solid-state ionics, analogous to the field of solid-state electronics. Only basic knowledge of physical chemistry and thermodynamics is required to read this book with utility. The chapters can be read independently from one another. - The. author, well known from his many publica-... 

Goodisman, J., Electrochemistry Theoretical Foundations, Quantum and Statistical Mechanics, Thermodynamics, the Solid State, Wiley, New York, 1987. 

Nernst, Walther (1864-1941 ) A German physical chemist, physicist, and inventor, Nernst discovered the Third Law of Thermodynamics—defining the chemical reactions affecting matter as temperatures drop toward absolute zero—for which he was awarded the 1920 Nobel Prize in Chemistry. He also invented an electric lamp, and developed an electric piano and a device using rare-earth filaments that significantly advanced infrared spectroscopy. He made numerous contributions to the specialized fields of electrochemistry, solid-state chemistry, and photochemistry. 

The electrochemistry of batteries Is a complicated phenomenon and thermodynamic data Is only applicable for equilibrium conditions and does not define overall kinetics. Including charge transfer, overpotential and rates. To date quantum mechanics and solid state theory has provided no understanding In defining the behavior of real batteries or cells. Battery research needs an Interdisciplinary approach of electrochemistry, material science, and various disciplines of engineering and above all a can-do Innovative spirit which Is somewhat missing In some of today s big science approach where publications are the highest form of achievement. 

Walther Hermann Nernst (1864-1941, Nobel Prize in Chemistry in 1920), a German chemist, is one of the founders of modern physicai chemistry. He worked on thermodynamics, electrochemistry, solid state and photochemistry, osmotic pressure, and electroacoustics. In 1887 he invented the Nernst lamp by using an incandescent ceramic rod (a precursor of the incandescent lamp). He established the third law of thermodynamics that describes the behavior of matter as the temperature approach absolute zero (1905). In association with the companies Bechstein and Siemens, he also invented the electric piano (1930) to produce electronically modified sound in the same way as an electric guitar. 

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