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Background and dawn of electrochemistry The 16th Century marked the beginning of the electrical understanding that culminated with the industrial Production Of Electrical Power in the late 19th Century . On 1550s English scientist William Gilbert spent 17 years experimenting with Magnetism and, to a lesser extent, electricity. For his work on magnets, Gilbert became known as the ''"Father of Magnetism."'' He discovered various methods for producing and strengthening magnets. Gilbert's De Magnete quickly became the standard work throughout Europe on electrical and magnetic phenomena. Gilbert made the first clear distinction between magnetic and the amber effect (static electricity, as is known today). On his book ''"De Magnete"'' William stated a comprehensive review of what was known about the nature of magnetism. But it wasn't until the advent of the following century when the electrical concept gained scientific importance. Physicist Otto Van Guericke beside his electrical generator while conducting experiment.]] In 1663 German Physicist Otto Van Guericke created the first electric generator, which produced static electricity by applying friction in the machine. The generator was made of a large Sulfur ball cast inside a glass globe, mounted on a shaft. The ball was rotated by means of a crank and a Static Electric Spark was produced when a pad was rubbed against the ball as it rotated. The globe could be removed and used as source for experiments with electricity. Despite his advance on electrical concept, von Guericke did not recognized the effect he generated as static electricity but he did on noticing that like charges repelled each other. The 18th Century and birth of electrochemistry In 1709 , Francis Hauksbee at the Royal Society in London discovered that by putting a small amount of Mercury in the glass of Von Guericke's generator and evacuating the air from it, when a charge was built up on the ball and then his hand placed onto it, it would glow. Unknown to him he had created the Neon Light. Between 1729 and 1736 , two English scientists, Stephen Gray and Jean Desaguliers performed a series of experiments which showed that a Cork or other object as far away as 800 or 900 Feet could be electrified by connecting it to a rubbed glass tube with materials such as Metal Wires or Hempen string. They found that other materials, such as Silk , would not convey the effect. By mid— for ''"glass"''), or positive, electricity; and ''"resinous,"'' or negative, electricity. This was the ''two-fluid theory'' of electricity, which was to be opposed by Benjamin Franklin's ''one-fluid theory'' later in the century. In 1745 Jean-Antoine Nollet developed a theory of electrical attraction and repulsion that supposed the existence of a continuous flow of electrical matter between charged bodies. Nollet’s theory at first gained wide acceptance, but met its nemesis in 1752 with the publication of the French translation of Franklin’s ''"Experiments and Observations on Electricity"''. Franklin and Nollet found themselves on opposite sides of current debate about the nature of electricity, with Franklin supporting action at a distance and two qualitatively opposing types of electricity, and Nollet advocating mechanical action and a single type of electric fluid. Franklin's argument eventually won and Nollet’s theory was abandoned. In 1748 Nollet invented one of the first Electrometer s, the Electroscope , which showed the presence of electric charge by using Electrostatic Attraction and repulsion. Nollet is reputed to be the man who first applied the name ''" Leyden Jar "'' to the first device for storing electricity. Nollet's invetion was superseeded by Horace-Bénédict De Saussure's electrometer in 1766 . By 1740s Sir William Watson conducted several experiments to determine the velocity of electricity. The general belief at the time was that electricity was faster than sound, but no accurate test had as yet been devised to measure the velocity of a current. Watson, in fields north of London, laid out a line of wire supported by dry sticks and silk which ran for 6.4 Km . Even at this length the ''"Velocity of Electricity was instantaneous."'' Resistance in the wire was also noticed but apparently not fully understood, as Watson relates that ''we observed again, that although the electrical compositions were very severe to those who held the wires, the report of the Explosion at the prime Conductor was little, in comparison of that which is heard when the Circuit is short.'' Watson eventually decided not to pursue his electrical experiments concentrating instead upon his medical career. By 1750s , as the study of electricity became popular, efficient ways of producing electricity were sought. The generator developed by Jesse Ramsden was among the first electrostatic generators invented. Electricity produced by such generators was used to treat paralysis and muscle spasms, and to control heart rates. Other medical uses of electricity included filling the body with electricity, drawing sparks from the body, and applying sparks from the generator to the body. Charles-Augustin De Coulomb developed the law of electrostatic attraction in 1781 as an outgrowth of his attempt to investigate the law of electrical repulsions as stated by Joseph Priestley on England. To this end he invented sensitive apparatus to measure the electrical forces involved in Priestley's law. He also established the inverse square law of attraction and repulsion of unlike and like magnetic poles, which became the basis for the mathematical theory of magnetic forces developed by Siméon-Denis Poisson . He wrote seven important treatises on electricity and magnetism which he submitted to the ''Académie des Sciences'' between 1785 and 1791 in which he reported having developed a theory of attraction and repulsion between bodies of the same and opposite electrical charge. He demonstrated an inverse square law for such forces and went on to examine perfect conductors and dielectrics. He suggested that there was no perfect dielectric, proposing that every substance has a limit above which it will Conduct electricity. In 1789 Franz Aepinus developed a device with the properties of a Condenser (now known as a Capacitor .) The Aepinus condenser was the first condenser developed after the ''Leyden jar'' and was used to demonstrate conductive and inductive Electricity . The device is constructed so that the space between the plates can be adjusted and the glass dielectric (insulating plate between them) can be removed or replaced with other materials. diagram of Galvani's experiment on frog legs.]] Despite 18th Century 's discoveries over electrical understanding were some sort successful to demonstrate many electrical properties and even electrical generators were made, it wasn't until late 1700s when Italian Physician and Anatomist Luigi Galvani marked the birth of electrochemistry by stablishing a bridge between electrical reactions and electricity on his essay ''"De Viribus Electricitatis in Motu Musculari Commentarius"'' (translated from Latin, Commentary on the Effect of Electricity on Muscular Motion) in 1791 where he proposed a ''"nerveo-electrical substance"'' on biological life forms. On his essay Galvani concluded that animal tissue contained a here-to-fore neglected innate, vital force, which he termed ''"animal electricity,"'' which activated Nerve and Muscle when spanned by Metal Probe s. He believed that this new force was a form of electricity in addition to the ''"natural"'' form that is produced by Lightning or by the Electric Eel and Torpedo Ray and to the ''"artificial"'' form that is produced by Friction (i.e., static electricity). He considered the Brain to be the most important organ for the secretion of this ''"electric fluid"'' and the nerves to be conductors of the fluid to the nerve and muscle, the Tissue s of which act as did the outer and inner surfaces of the ''Leyden jar''. The flow of this electric fluid provided a Stimulus for the irritable Muscle Fibres , according to his explanation. Physicist Alessandro Volta showing his ''" Battery "'' to French Emperor Napoleon Bonaparte in early 1800s .]] Galvani's scientific colleagues generally accepted his views, but Alessandro Volta , the outstanding professor of Physics at the University Of Pavia , was not convinced by the analogy between the Muscle and the Leyden Jar . Deciding that the ''frog's legs'' served only as an indicating Electroscope , he held that the contact of dissimilar metals was the true source of stimulation; he referred to the electricity so generated as ''"metallic electricity"'' and decided that the muscle, by contracting when touched by metal, resembled the action of an electroscope. Furthermore, Volta said that, if two dissimilar metals in contact both touched a muscle, agitation would also occur and increase with the dissimilarity of the metals. Thus Volta rejected the idea of an ''"animal electric fluid,"'' replying that the frog's legs responded to differences in Metal Temper , composition, and Bulk . Galvani refuted this by obtaining muscular action with two pieces of the same material. Rise of Electrochemistry as branch of chemistry In 1800 , English chemists William Nicholson and Johann Ritter succeeded in decomposing water into Hydrogen and Oxygen by Electrolysis . Soon thereafter Johann discovered the process of Electroplating . He also observed the amount of metal deposited and the amount of oxygen produced during an electrolytic process that depended on the distance between the Electrodes . By 1801 Ritter observed Thermoelectric Currents and anticipated the discovery of thermoelectricity by Thomas Johann Seebeck . In 1802 , William Cruickshank designed the first electric battery capable of mass production. Cruickshank had arranged square sheets of Copper , which he soldered at their ends, together with sheets of Zinc of equal size. These sheets were placed into a long rectangular wooden box that was sealed with Cement . Grooves in the box held the metal plates in position. The box was then filled with an electrolyte of Brine , or watered down acid. This flooded design had the advantage of not drying out with use and provided more energy than Volta's disc arrangement. In the quest for a better production of platinum metals two scientists William Hyde Wollaston and Smithson Tennant worked together to design an efficient electrochemical technique would refine platium. Tennant ended up discovering the new elements of Iridium and Osmium . Wollaston's effort, in turn, led him to the discovery of the new metals Palladium ( 1803 ) and Rhodium ( 1804 ). By 1810s Wollaston made improvements to the Galvanic Pile . In Wollaston's battery the copper plates were doubled (a copper plate bent round into a U-shape) with a single plate of zinc placed in the center of the bent copper. The zinc plate was prevented from making contact with the copper by pieces or Dowel s of Cork or wood. In his single cell design, the copper U-shaped plate was welted to a horizontal handle for lifting the copper and zinc plates from the activating solution when the battery was not in use. The metal plates and the solution were contained in an earthenware vessel. In 1809 Samuel Soemmering developed the first Telegraph . He used a device with 26 Wires (1 wire for each letter of the German Alphabet ) terminated in a container of Acid . At the sending station, a key, which brought a battery into the circuit, was connected as required to each of the line wires. The passage of a Current caused the acid to decompose chemically and the message was read by observing at which of the terminals the bubbles of gas appeared. This is how he was able to send messages, one letter at a time. Sir Humphry Davy work with electrolysis led to conclude that the production of electricity in simple Electrolytic Cell s resulted from chemical action and that chemical combination occurred between substances of opposite charge. He therefore reasoned that electrolysis, the interactions of electric currents with chemical compounds, offered the most likely means of Decomposing all substances to their elements. These views were explained in 1806 in his lecture ''"On Some Chemical Agencies of Electricity,"'' for which, despite the fact that England and France were at war, he received the Napoleon Prize from the Institut De France in 1807 . This work led directly to the isolation of Sodium and Potassium from their compounds and of the Alkaline-earth Metals from theirs in 1808 . Hans Christian Ørsted discovery of the magnetic effect of electrical currents in 1820 was immediately recognized as an epoch-making advance, although he left further work on Electromagnetism to others. André-Marie Ampère quickly repeated Oersted's experiment, and formulated them mathematically. Ørsted also discovered that not only is a magnetic needle deflected by the electric current, but that the live electric wire is also deflected in a magnetic field, thus laying the foundation for the construction of the electric motor. Ørsted's discovery of Piperine , one of the pungent components of pepper, was an important contribution to chemistry, as was his preparation of metallic Aluminum in 1825 . By 1820s Robert Hare developed the '' Deflagrator '', a form of voltaic battery having large plates used for producing rapid and powerful Combustion . A modified form of this apparatus was employed in 1823 in volatilizing and fusing Carbon . It was with these batteries that the first application of voltaic electricity to blasting under water was made in 1831 . In 1821 , Estonian-German Physicist Thomas Johann Seebeck demonstrated the electrical potential in the juncture points of two dissimilar metals when there is a Heat difference between the joints. He joined a copper wire with a Bismuth wire to form a loop or circuit. Two junctions were formed by connecting the ends of the wires to each other. He then accidentally discovered that if he heated one junction to a high temperature, and the other junction remained at a cooler temperature a Magnetic Field was observed around the circuit of different temperatures. He did not recognize, believe, or report that an Electrical Current was being generated when heat was applied to one junction of the two metals. He used the term thermomagnetic currents or Thermomagnetism to express his discovery. During the following two years, 1822 - 1823 , he reported on his continuing observations to the Prussian Academy Of Sciences , where he describes this observation as ''"the Magnetic Polarization of metals and ores produced by a temperature difference."'' This effect became the basis of the Thermocouple that still considered the most accurate measurement of temperature today. In 1827 German scientist Georg Ohm expressed his Law in this famous book ''"Die galvanische Kette, mathematisch bearbeitet"'' (The Galvanic Circuit Investigated Mathematically) in which he gave his complete theory of electricity. In 1829 Antoine-César Becquerel developed the Constant Current Cell , which was the forerunner of the well-known ''" Daniell Cell "''. When this acid- Alkali cell was monitored by a Galvanometer , current was found to be constant for an hour, the first instance of ''"constant current"''. He applied the results of his study of Thermoelectricity to the construction of an electric Thermometer and measured with it the temperature of the interior of animals, of the Soil at different depths, of the Atmosphere at different heights. He helped validate Faraday's Laws and conduct extensive investigations on the Electrodeposition of metals with applications for Metal Finishing and Metallurgy . Solar cell technology dates to 1839 when Antoine-César Becquerel observed that shining light on an Electrode submerged in a conductive solution would create an electric current. Michael Faraday began, in 1832 , what promised to be a rather tedious attempt to prove that all electricities had precisely the same properties and caused precisely the same effects. The key effect was Electrochemical Decomposition . Voltaic and electromagnetic electricity posed no problems, but static electricity did. As Faraday delved deeper into the problem, he made two startling discoveries. First, Electrical Force did not, as had long been supposed, act at a distance upon Chemical Molecules to cause them to dissociate. It was the passage of electricity through a conducting liquid medium that caused the molecules to dissociate, even when the electricity merely discharged into the air and did not pass into a ''" Pole "'' or ''"centre of action"'' in a Voltaic Cell . Second, the amount of the decomposition was found to be related in a simple manner to the amount of electricity that passed through the solution. These findings led Faraday to a new theory of electrochemistry. The electric force, he argued, threw the molecules of a solution into a state of tension. When the force was strong enough to distort the Fields Of Forces that held the molecules together so as to permit the interaction of these fields with neighboring particles, the tension was relieved by the migration of particles along the lines of tension, the different species of Atoms migrating in opposite directions. The amount of electricity that passed, then, was clearly related to the chemical affinities of the substances in solution. These experiments led directly to Faraday's two laws of electrochemistry by stating:
Hippolyte Pixii , a French instrument maker, constructed the first direct current Dynamo in 1832 . This was the first practical mechanical generator of electrical current that used concepts demonstrated by Faraday. William Sturgeon built an Electric Motor in 1832 and invented the Commutator , an integral part of most modern electric motors. He also improved the voltaic battery and worked on the theory of thermoelectricity. John Daniell began experiments in 1835 in an attempt to improve the Voltaic battery with its problem of being unsteady and as a weak source of electrical current. His experiments soon led to remarkable results. In 1836 , he invented a primary cell in which Hydrogen was eliminated in the generation of the electricity. Daniell had solved the problem of Polarization . In his laboratory he had learned to Alloy the Amalgamated Zinc of Sturgeon with Mercury . His version was the first of the two-fluid class battery and the first battery that produced a constant reliable source of electrical current over a long period of time. William Grove produced the first Fuel Cell in 1839 . He based his experiment on the fact that sending an Electric Current through water splits the water into its component parts of Hydrogen and Oxygen . So, Grove tried reversing the reaction - combining Hydrogen and Oxygen to produce electricity and water. Eventually the term ''"fuel cell"'' was coined later in 1889 by Ludwig Mond and Charles Langer , who attempted to build the first practical device using air and Industrial Coal Gas . He also introduced a powerful battery at the annual meeting of the ''British Association for the Advancement of Science'' in 1839 . Grove's first cell consisted of zinc in dilute Sulfuric Acid and Platinum in concentrated Nitric Acid , separated by a porous pot (Grove Battery). The cell was able to generate about 12 Amps of current at about 1.8 Volts . This cell had nearly double the voltage of the first Daniell cell. Grove's nitric acid cell was the favorite battery of the early American telegraph ( 1840 - 1860 ), because it offered strong current output. As telegraph traffic increased, it was found that the Grove cell discharged Poisonous Nitric Dioxide gas. Large telegraph offices were filled with gas from rows of hissing Grove batteries. As telegraphs became more complex, the need for constant voltage became critical and the Grove device was necessarily limited (as the cell discharged, nitric acid was depleted and voltage was reduced). By the time of the American Civil War , Grove's battery was replaced by the Daniell battery. In 1841 Robert Bunsen replaced the expensive platinum electrode used in Grove's battery, with a Carbon electrode. This led to large scale use of the ''"Bunsen battery"'' in the production of arc-light and in Electroplating . Wilhelm Weber developed, in 1846 , the Electrodynamometer , in which a current causes a Coil suspended within another coil to turn when a current is passed through both. In 1852 , Weber defined the absolute unit of Electrical Resistance . Johann Hittorf's concluded ion movement caused by electric current. In 1853 Hittorf noticed that some Ion s traveled more rapidly than others. This observation led to the concept of transport number, the rate at which particular ions carried the electric current. Hittorf measured the changes in the concentration of electrolyzed solutions, computed from these the transport numbers (relative carrying capacities) of many ions, and, in 1869, published his laws governing the migration of ions. In 1866 , Georges Leclanché patented a new system, which was immediately successful. Leclanche's original cell was assembled in a porous pot. The positive electrode consisted of crushed Manganese Dioxide with a little carbon mixed in. The negative pole was a Zinc rod. The cathode was packed into the pot, and a carbon rod was inserted to act as a currency collector. The anode or zinc rod and the pot were then immersed in an Ammonium Chloride solution. The liquid acted as the electrolyte, readily seeping through the porous cup and making contact with the cathode material. Leclanché's ''"wet"'' cell became the forerunner to the world's first widely used battery, the Zinc Carbon Cell . Late 19th century advances and the advent of Electrochemical societies In 1869 Zénobe Gramme devised his first clean Direct-current Dynamo . His generator featured a ring armature wound with many individual coils of wire. Svante August Arrhenius published his thesis in 1884 on ''Recherches sur la conductibilité galvanique des électrolytes'' (Investigations on the galvanic conductivity of electrolytes). From his results the author concluded that Electrolyte s, when dissolved in water, become to varying degrees split or dissociated into electrically opposite positive and negative ions. The degree to which this dissociation occurred depended above all on the nature of the substance and its concentration in the solution, being more developed the greater the dilution. The ions were supposed to be the carriers of the electric current, E.g. in electrolysis, but also of the chemical activity. The relation between the actual number of ions and their number at great dilution (when all the molecules were dissociated) gave a quantity of special interest ("activity constant"). The race for a commercially viable route to Aluminum was won in 1886 by, Paul Héroult and Charles M. Hall . The problem many researchers had with extracting aluminum was that Electrolysis of an Aluminum Salt dissolved in water yields Aluminum Hydroxide . Both Hall and Héroult avoided this problem by dissolving aluminum oxide in a new solvent—fused Cryolite , Na 3 Al F 6. Friedrich Ostwald , 1909 Nobel Laureate , started his experimental work in 1875 , with an investigation on the law of mass action of water in relation to the problems of chemical affinity, with special emphasis on electrochemistry and Chemical Dynamics . In 1894 he gave the first modern definition of a Catalyst and turned his attention to catalytic reactions. Ostwald is especially known for his contributions to the field of electrochemistry, including important studies of the Electrical Conductivity and electrolytic dissociation of Organic Acid s. Hermann Nernst's developed the theory of the Electromotive Force of the voltaic cell in 1888 . He developed methods for measuring Dielectric Constant s and was the first to show that solvents of high dielectric constants promote the ionization of substances. Nernst's early studies in electrochemistry were inspired by Arrhenius' dissociation theory which first recognized the importance of ions in solution. In 1889 he elucidated the theory of galvanic cells by assuming an ''"electrolytic pressure of dissolution"'' which forces ions from electrodes into solution and which was opposed to the osmotic pressure of the dissolved ions. Nernst applied the principles of Thermodynamics to the chemical reactions proceeding in a battery. In 1889 , he showed how the characteristics of the current produced could be used to calculate the Free Energy change in the chemical reaction producing the current. He constructed an equation, known as Nernst Equation , which related the voltage of a cell to its properties. In is kept constant. In 1898 he explained the reduction of Nitrobenzene in stages at the cathode and this became the model for other similar reduction processes. In 1909 , Robert Andrews Millikan began a series of experiments to determine the electric charge carried by a single Electron . He began by measuring the course of charged water droplets in an electrical field. The results suggested that the charge on the droplets is a multiple of the elementary electric charge, but the experiment was not accurate enough to be convincing. He obtained more precise results in 1910 with his famous Oil-drop experiment in which he replaced water (which tended to evaporate too quickly) with oil. Jaroslav Heyrovský , Nobel laureate, eliminated the tedious weighing required by previous Analytical Techniques using the differential precipitation on mercury step by monitoring drop-time. In the previous method a voltage was applied to a dropping mercury electrode and a reference electrode was immersed in a test solution. After 50 drops of mercury were collected, they were dried and weighed. The applied voltage was varied and the experiment repeated. Measured weight was plotted vs. applied voltage to obtain the curve. In 1921, he had the idea of measuring the current flowing through the cell instead of just studying drop-time. On February 10 1922 , the ''" Polarograph "'' was born as Heyrovský recorded the current-voltage curve for a solution of 1 M NaOH . Heyrovský correctly interpreted the current increase between -1.9 and -2.0 V as being due to deposition of Na+ ions, forming an amalgam. Shortly thereafter, with his Japanese colleague, Masuzo Shikata , he constructed the first instrument for the automatic recording of polarographic curves, which became world famous later as the Polarograph . In 1923 , Johannes Nicolaus Brønsted and Thomas Martin Lowry published essentially the same theory about how acids and bases behave using electrochemical basis. The International Society Of Electrochemistry (ISE) was founded in 1949 , and some years later the first sophisticated Electrophoretic apparatus was developed in 1937 by Arne Tiselius , who was awarded the 1948 Nobel Prize for his work in protein Electrophoresis . He developed the ''"moving boundary,"'' which later would become known as zone electrophoresis, and used it to separate serum proteins in solution. Electrophoresis became widely developed in the 1940s and 1950s when the technique was applied from molecules ranging from the largest proteins to Amino Acids or even inorganic ions. By the 1960s – 1970s Quantum Electrochemistry was developed by Revaz Dogonadze and his pupils. SEE ALSO
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