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ECS Classics (continued from previous page) dielectric constants facilitated ionization of substances. Students of physical chemistry know him through the Nernst equation. Tutored by Hermann Kolbe at Marburg and Robert Bunsen at Heidelberg, Ludwig Mond (1839-1909) became a well known chemist and industrialist. Initially, his interests were in the production of elemental sulfur, alkali, and ammonia. He also developed a process (the Mond process) for the generation of producer gas. In 1889, he and his assistant Carl Langer developed a hydrogen–oxygen fuel cell with thin perforated platinum electrodes. Both Mond and Langer were instrumental in popularizing fuel cells. In their attempt to use coal gas as a fuel in fuel cells, they discovered the formation of nickel carbonyl (the molecules described by Lord Kelvin as metals with wings) from the carbon monoxide in the coal gas and the nickel in the electrode. This observation formed the basis of the Mond process for the extraction of nickel through a carbonyl route. In 1890, inventive genius and businessman Herbert Henry Dow (1866-1930), best known for his work on halogen chemistry, developed an electrolytic method for the production of bromine from brine. Today, the method is known as the Dow process. An offshoot of this work was an electrolytic production route for chlorine. Slowly, and with the establishment of the Dow Chemical Company, he ventured into chlorine chemicals, organics, and later into magnesium metal and calcium. By capitalizing on the brine sourced from the ancient seas in the Midland region of the U.S., Dow opened avenues for mining sea resources. The first to record a human electrocardiogram with the Lippmann’s mercury capillary electrometer was Herbert Henry Dow Augustus Desire Waller* (1856- 1922), the French physiologist who in 1887 thought up the idea of using the body itself as an electrical conductor. Willem Einthoven (1860-1927) improved upon Waller’s experiments and instrumentation. In 1893, Edward Weston (1850-1936) developed a standard cell that was to become the international standard for the calibration of voltmeters. The cell was less sensitive to temperature fluctuations than the previous standard, Edward Weston the Clark cell, and had the additional advantage of possessing a voltage very close to a volt: 1.0183 V. Based on his work on electrolysis, Fritz Haber (1868-1934) in 1898 showed that different products could be obtained by maintaining the potential of the electrode at different values. He explained his findings with nitrobenzene, which became a model compound for other investigators. He also worked on the quinonehydroquinone transformation, which became the basis for Biilmann’s Fritz Haber quinhydrone electrode for measuring _______________ *The first human electrocardiogram was recorded by Alexander Muirhead (1848-1920), but it was Waller who did it in a clinico-physiological setting. Moreover, Muirhead used a Thompson siphon recorder for his measurements while Waller used Lippmann’s capillary electrometer. the acidity of solutions. Haber is also credited with the invention of the glass electrode, a contribution he made with Cremer, one of his associates. This was also a period that witnessed as many as 1,093 inventions by a single person, Thomas Alva Edison (1847- 1931), nicknamed the “Wizard of Menlo Park.” Although he is most popular for inventing the incandescent bulb and the phonograph, his unveiling of the nickel–iron accumulator was no less a contribution. Simultaneously, and independently of Edison, Waldemar Thomas Edison Jungner (1869-1924) in Sweden patented the nickel-iron battery. In 1899 Jungner replaced the iron electrode with the more efficient cadmium electrode. It is interesting to note that in 1899 the world record for road speed was held by the electric vehicle! However, with rapid advancements in internal combustion engineering, the bottom fell off the electric vehicle market in the next three decades. The year 1898 marked a turning point in organic electrochemistry with Swiss chemist Julius Tafel (1862- 1918) demonstrating the use of lead as an electrode for the reduction of organic compounds. Tafel, who was both an organic chemist and a physical chemist, made seminal contributions to organic electrochemistry and established the Tafel equation connecting the rates Julius Tafel of electrochemical reactions and overpotential. The Tafel equation was unique in that it could be applied to irreversible electrochemical reactions that could not be described by thermodynamics. The several contributions he made in organic chemistry include reduction with amalgams and the Tafel rearrangement. Tafel is also known for introducing the hydrogen coulometer for measurement of electrochemical reaction rates and pre-electrolysis as a method for purifying solutions. Twentieth Century: First Half Thermodynamic considerations and ionic transport were the focus of this period. In one of the first approaches to characterizing aqueous solutions, H. Friedenthal in 1904 suggested the use of hydrogen ion concentrations. In what is probably the beginning of the concept of pH, Friedenthal also found that the product of the concentrations of hydrogen ions and hydroxyl ions in aqueous solutions was always 1 x 10 -14 . It must be pointed out, however, that the concept of pondus hydrogenii, or pH, itself was introduced five years later by the Danish chemist Søren Peder Lauritz Sørensen (1868-1939). In what was to mark the beginning of bioelectrochemistry, Julius Bernstein (1839-1917), of the University of Berlin, demonstrated that the action electric potential in nerves was the result of a change in ionic properties of the nerve membrane. He proposed his membrane hypothesis in two parts, the first one in 1902 and the second in 1912. His theory was based on the work of Helmholtz and Du Bois-Reymond (1818-1896), the “father of experimental electrophysiology.” Bernstein’s work on the propagation of nerve impulses and trans-membrane potential led to great interest in bioelectricity and in the theory of nerve action in particular. It is noteworthy that Bernstein’s work was the last nail on animal electricity, and came at a time when electricity was trying to rid itself of the shadow of biology. In 1910, Robert Andrews Millikan (1868-1953) determined the charge on an electron by his famous oil drop experiments. The following year, Frederick George Donnan (1870-1956) established the conditions for 36 The Electrochemical Society Interface • Fall 2008
equilibrium between two electrolytic solutions separated by a semi-permeable membrane. Today, Donnan’s name is associated with both the nature of the equilibrium and the potential across the membrane. Around 1922, Prague evolved into the “Mecca of electrochemistry.” On February 10 of that year, Jaroslav Heyrovsky (1890-1967), sometimes called the “father of electroanalytical chemistry,” recorded a current–voltage curve for a solution of sodium hydroxide using a dropping mercury electrode and ascribed the current jump between –1.9 and –2.0 V to the deposition of sodium Jaroslav Heyrovsky ions on mercury. This marked the beginning of polarography, which took roots in his early work with F. G. Donnan on the electrode potential of aluminum, leading Heyrovsky into work on liquid electrodes that provide a continuously renewable electrode surface. Later, he teamed up with Masuzo Shikata (1895-1964) and designed the first recording polarograph. In 1959, Heyrovsky was awarded the Nobel Prize for his seminal work on this electroanalytical technique. Polarography led to a spurt in the growth of the theory of electrochemical reactions and mass transport in electrolyte solutions, and laid the fundamentals of all voltammetric methods employed in electroanalysis. In 1929, Heyrovsky along with Emil Votocek of the Prague Technical University, founded the journal, Collection of Czechoslovak Chemical Communications. Slovakian physical chemist and mathematical physicist Dionyz Ilkovic (1907-1980), a research assistant to Heyrovsky, was one of the co-founders of polarography. The basic equation of polarography, the Ilkovic equation, goes by his name. Relationships between molecular structure and electrical properties were also beginning to be unraveled. In 1923, Johannes Nicolaus Bronsted (1879-1947) in Denmark and Thomas Martin Lowry (1874-1936) in England propounded, independently of each other, a theory on acids and bases. According to them, an acid was a compound with a tendency to donate a proton (or hydrogen ion), while a base was one that combined with a proton. The same year also witnessed Dutch-American physicist Petrus Josephus Wilhelmus Debye (1884- 1966) and German physicist and Petrus Debye physical chemist Erich Armand Arthur Joseph Huckel (1896-1980) elucidating fundamental theories concerning the behavior of strong electrolyte solutions. According to them, electrolyte solutions deviate from ideal behavior due to ion–ion attractions. They suggested that ions in solutions have a screening effect on the electric field from individual ions, which gave rise to the Debye length. Huckel is also famous for the Huckel rule for determining ring molecules and for the Huckel method of approximate molecular orbital calculations on π-electron systems. Debye won the 1936 Nobel Prize in Chemistry for his contributions to molecular structure, for dipole moment relationships and for diffraction of X-rays and electrons in gases. In 1916, he showed that X-ray diffraction studies could be done with powder samples, eliminating in the process the need to prepare good crystals. This has come to be known as the Debye–Scherrer X-ray diffraction method. The originality and extent of Debye’s contributions are reflected in the many concepts that carry his name: the Debye–Scherrer method of X-ray diffraction, Debye–Huckel theory, Debye theory of specific heat, Debye–Sears effect in transparent liquids, Debye shielding distance, Debye temperature, Debye frequency, and the Debye theory of wave mechanics. He is also immortalized by the CGS unit for dipole moment (debye), the Dipole Moment monument in Maastricht, and the American Chemical Society award in his name. Alexander Frumkin Veniamin Grigorevich Levich Thomas Percy Hoare Ulick Evans Herbert H. Uhlig Carl Wagner Around this time, Alexander Naumovich Frumkin (1895-1976), popularly known as the “father of electrochemistry in Russia,” made vital contributions to our knowledge of the fundamentals of electrode reactions—particularly the influence of the electrode–electrolyte interface on the rate of electron transfer across it. Based on his studies on the adsorption of organic compounds on mercury, Frumkin proposed an adsorption isotherm that has come to be known as the Frumkin isotherm. He also introduced the concept of potential of zero charge. He joined hands with Veniamin Grigorevich Levich (1917-1987), an associate of theoretical physicist Lev Davidovich Landau (1908-1968), in relating his experimental results to theory. The collaboration led to the development of the rotating disc electrode and to a quantitative analysis of the polarographic maximum. Electric traction received a boost with the invention of the so-called Drumm traction battery. This was a nickel-zinc alkaline battery invented by James J. Drumm (1897-1974) and it became popular with its use in a suburban train in Ireland. In 1932, Francis Thomas Bacon (1904-1992) introduced the use of an alkaline electrolyte and inexpensive nickel electrode in fuel cells. Twenty-seven years later, in 1959, he demonstrated a practical fivekilowatt fuel cell. The quantitative measurement of electrochemical corrosion got established with a 1932 publication of Thomas Percy Hoare (1907- 1978) and Ulick Richardson Evans (1889-1980). Evans, the 1955 ECS Olin Palladium Award winner, described in the Biographical Memoirs of Fellows of the Royal Society as the “father of the modern science of corrosion and protection of metals,” laid the foundations of the electrochemical nature of corrosion. His 1937 book Metallic Corrosion, Passivity, and Protection is probably the most comprehensive book ever written by a single author on corrosion science. In 1933, in a paper on the oxygen electrode, Hoare showed how equilibrium potential could be determined from Tafel plots. Hoare was the first recipient of the U. R. Evans award (1976) of the Institution of Corrosion Science and Technology. Herbert H. Uhlig (1907-1993) was another champion of corrosion science. He helped establish the ECS Corrosion Division. His Corrosion Handbook published in 1948 continues to serve generations of corrosion scientists and engineers even half a century after its publication. Described by F. Mansfeld as “an under-appreciated giant in the world of electrochemistry and corrosion,” German electrochemist and materials scientist Carl Wagner (1901-1977) is also remembered as the “father of solid- (continued on next page) The Electrochemical Society Interface • Fall 2008 37
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ECS Classics - The Electrochemical Society

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