The electrochemistry is a discipline of the Chimie which knew many changes during its evolution since the first principles of the Aimant S at the beginning of the XVIe century and the XVIIe century for then leading to theories using the concepts of Conductivité, of the electric charges as well as mathematical methods. The electrochemistry term was used to describe the electric phenomena with the XIXe century and with the XXe century During last decades, electrochemistry was a broad field of the research in which formed part the study of the battery S and the combustible batteries, and the development of techniques to avoid the Corrosion metals and to improve the techniques of Raffinage thanks to electrolysis S and the electrophoresis S.
Origins of electrochemistry
The XVe century mark the beginning of the scientific comprehension of the electricity and the Magnetism with the production of electrical energy which allowed the industrial revolution during the XIXe century. In the years 1950, an English scientist William Gilbert made experiments during 17 years on magnetism and then on electricity. For its work on the magnets, he becomes the father of magnetism. Its book De Magnete quickly becomes a reference through Europe on the electric and magnetic phenomena. Europeans started has to make the long ones travels on the oceans and the magnetic compass was L one of the instruments of navigation very much used not to lose itself. He was the first man to make a clear distinction between the magnetism and the “effect of Ambre”, i.e. the static electricity.In 1663, a German physicist, Otto von Guericke created the electric first Générateur, which produced static electricity by friction. The generator was made of broad a ball of suffers inside a sphere out of glass, assembled on a stem. The sphere was put in rotation thanks to a lever and friction gave place to static electricity. The sphere could be moved and used like a source of electricity in experiments. Von Guericke used its generator to prove that loads of comparable nature are pushed back.
The XVIIe century and birth of electrochemistry
In 1709, Francis Hauksbee with the Royal Society of London discovered that to put an minor amount of mercury in the sphere of the generator of Von Guericke and by evacuating the air of that Ci enabled him with the generator to shine even in concerning hand. It had creates the first fluorescent Lampe.
Between 1729 and 1736, two English scientists Stephen Gray and Jean Desaguliers carried out a series of experiments which showed that a stopper of cork or another object can be electrified at a distance of 245-275 m by connecting it to the sphere of glass charged via materials like a metal wire or a cord of hemp. They also discovered that other materials as silk did not produce the same phenomenon.
In the middle of the XVIIIe century, a French chemist François de Cisternay Of Fay discovered two forms of static electricity in which the loads are pushed back or attract. He announced that electricity consisted of two fluids: vitreus (the Latin word to say Glass) or positive electricity and resinus or negative electricity. This design of the two fluids met a little later in the century the opposition of the single fluid theory of Benjamin Franklin.
In 1745, Jean-Antoine Nollet developed the theory of attraction and the electric repulsion which supposed the existence of a continuous electric matter flow between the two bodies charged. The theory of Nollet at the beginning was accepted then met resistance in 1752 with the translation in French of the note Franklin Experiments and Observations one Electricity . Franklin and Nollet discussed about the nature of electricity. The argumentation the Franklin one deferred the victory and the theory of Nollet was abandoned.
In 1748, Nollet invented one of the first electrometer S, the electroscope which made it possible to observe the electric charges by using attraction and the electrostatic repulsion. The invention of Nollet was consequently replaced by the electrometer of Horace-Bénédict de Saussure in 1766.
William Watson undertook several experiments to know the speed of electricity. The general opinion of the time was that electricity was faster than the sound but no test had made it possible to determine the current velocity. Watson in a field in the north of London tightened a discussion thread supported by wet silk stakes. Even at this distance from 3.7 km, the propagation velocity of the current seemed instantaneous. Resistance in the discussion thread was noticed but entirely not apprehended by Watson and it decided not to continue the experiments on electricity in order to concentrate on its medical career.
In the years 1750, whereas the study of electricity became popular, of the effective methods of electrical productions appeared. The generator developed by Jesse Ramsden was among one of the first electrostatic generators. The electricity produced by the generators was used to treat the muscular paralyzes and spasms.
Charles-Augustin of Coulomb developed the law of the electrostatic interaction in 1781 after having studied the laws of the repulsion of Joseph Priestley in England. It establishes also the formula of the reverse of the square of the law of attraction and repulsion which became the mathematical base of the theory of the magnetic forces of Siméon-Denis Poisson. Coulomb wrote seven important work on magnetism and the electricity which it presented to the Academy of Science between 1785 and 1791 in which it deferred to have developed a theory of attraction and of repulsion between the bodies charged and he had managed from there to undertake research on the perfect drivers and the Diélectrique S. He suggested that the dielectric perfect ones did not exist, that each substance had its limits with the top of which ran passed. The unit of load of the International Système is called Coulomb in its honor.
In 1789, Franz Aepinus developed an object with the properties of a Condensateur. The condenser of Aepinus was the first condenser since the Leyden jar and was used to show the phenomena of conduction and induction. The object was manufactured in such a way that space between the two conducting plates was adjustable and dielectric glass separating the two plates could be removed or replaced by another material.
In spite of the increase in knowledge on the properties of electricity and the construction of generators, it was not before the end of the XVIIIe century that the Italian physicist and anatomist Luigi Galvani noticed a bond between the muscular contraction and electricity in 1791 when he wrote De Viribus Electricitatis in Motu Musculari Commentarius . He proposed the existence of a nervoelectric substance in the life. In its test, Galvani concludes that the animal fabrics contain an innate substance until there unknown, a vital force to which it gave the name of “animal electricity” which activates the muscles when it is placed between two metal probes. He believed that it was about a new form of electricity and that the brain was the most important body for the secretion of the electric fluid. The nerves had as a role to lead this fluid to the muscles. The flow of this electric fluid caused a Stimulus with muscle fibers.
But it is the March 17th 1800 which the Italian scientist Alessandro Volta tests successfully the first Battery and marks the birth of electrochemistry.
The great development of electrochemistry
The first electrolysis was carried out on May 2nd 1800 by two British chemists, and, a few days after the invention of the first Battery by Alessandro Volta (publication submitted on March 20th, 1800 in a French letter to the president of the Royal Society). By using the pile of Volta, the two scientists carry out a electrolysis of water and succeed in transforming water into Dihydrogène and Dioxygène. A little later Ritter discovers the principle of Galvanoplastie. It observed that during a electrolysis a quantity of metal produces a quantity of oxygen which depends on the distance between the electrode S. In 1801, Ritter observed thermoelectric currents and it anticipated the discovery of the Thermoélectricité by Thomas Johann Seebeck.
In 1802, William Cruikshank designs the first electric battery being able to be produced in great quantity. Like Volta, it arranges square plates of Cuivre, which it will sell until the end as well as plates of Zinc of the same size. These plates were placed in long limps rectangular which was sealed with cement. Slits in limps allowed the plates metal to remain in position. Limps was then filled of brine or acid water. This flood has the advantage of not evaporating and provides more energy than the Pile of Volta or coated brine papers between the plates.
With an aim of a better production of metal Platinum, two scientists William Hyde Wollaston and Smithson Holding worked together to conceive an effective technique of electrochemistry to refine or purify the Platine. Holding ends up discovering the Osmium and Iridium. The efforts of Wollaston enabled him to discover the palladium in 1803 and the Rhodium in 1804.
In 1809, Samuel Thomas Von Soemmering developed the first Télégraphe. He used an assembly with 26 cables (a cable for each German letter of the alphabet). Each one of these cables finished in a reserve of acid. At the station of sending, a letter was supplemented by a circuit and a battery was connected. The passage of the current chemically broke up the acid and the message was read while observing at which end of cable the bubbles appeared. The messages were transmitted in this manner, a letter at the same time.
Work of Sir Humphry Davy with the electrolysis S brought to the conclusion that the electrical production in the simple cells electrolytic results from interactions between the electrolyte S and metals and occur between species of different loads. It observed that the interaction between the electric current and the chemicals generally gave all the basic substances comprising the elements. This vision of the things was explained in 1806 in the reading One off Summons Chemical Agencies Electricity for which it accepted the Prix Napoleon (although France and England were in war at that time). Its work led directly to the insulation of the Sodium and the Potassium starting from their current compounds and of other alkaline metals as from 1808.
The discovery of the effect of magnetism on the current in 1820 by Hans Christian Ørsted was immediately recognized like a large projection. However, it gave up its work on electromagnetism with the others. Andre-Marie Ampère repeated the experiments of Ørsted and he formulated them mathematically (what became the law of Amp). Ørsted discovered that not only one needle is attracted by an electric current but also that the electric wire in entirety is attracted by an electric field, which is the base for the construction of an electrical motor. Ørsted discovered also the Pipérine, an important component of the Piment, which was an important contribution to chemistry as well as the preparation of the Aluminum in 1825.
In 1821, the German Estonian physicist Thomas Johann Seebeck showed the electric Potentiel of junction points of two different metals when there is difference in temperature between the joints. He united a copper wire with a wire of Bismuth to form a loop or a circuit. The junctions were formed by binding the ends of two wire. He discovered accidentally that if he heats one of the junctions at high temperature and that the other junction remains with room temperature, a Magnetic field is then observed in the circuit.
He did not recognize that an electric current was generated when he made the junction bimetal. He used the term “thermomagnetism” or “thermomagnetic current” to describe his discovery. During the two following years, it deferred its observations to the Prussia Academy of Sciences or it described its observations on the polarizability of metals and the ores produced by a difference in temperature. This Seebeck effect became the base of the Thermocouple, which is regarded as the most exact method to measure temperatures today. The opposite effect said Peltier effect of appearance of a difference in temperature when a current traverses a circuit with different metals was observed only after ten years of controversy.
In 1827, a German scientist Georg Ohm expresses his famous law in his book Die galvanische Kette, mathematisch bearbeitet , studied galvanic circuit the mathematically in which it gives his complete theory of electricity.
In 1829 Antoine-César Becquerel invented the cell of precursory constant current of the pile Daniel, very known. The pile consisted of a zinc plate in acid medium and of a copper plate in a solutionde copper sulfate. When this pile of acid with the alkaline ones was controlled by a galvanometer, the current appeared constant during one hour, the beginning of the constant current. It applied the result of its study of thermoelectricity to build an electric thermometer and to measure the temperature inside the animals been able the ground with a different depth or the atmosphere at different altitudes. It helped to validate the laws of Faradays and undertook large research on the electrodeposition of metals with for application the completion of metals and the metallurgy. The technology of the solar cells goes back to 1839 when Becquerel observed that the sun rays on an electrode plunged in a conducting solution create an electric current.
Michael Faraday started in 1832, which promised being a spot tiresome to prove that all electricities had the same properties and to cause the same effects. The key effect was the electro decomposition. Voltaic and electromagnetic energy did not pose any problems but static electricity posed a problem. Whereas Faraday was interested in the problem, it made two discovered departure. Firstly, the electric force does not break up the molecules has distances as that was supposes. It is about the passage of electricity in a conducting liquid medium which makes that the molecule dissociates even when electricity discharges in the airs and does not pass by a pole or centers action in the piles voltaic. Secondly, the quantity of decomposition was being related to the quantity of electricity passing through the solution.
These discoveries carried out Faraday to establish a new theory of electrochemistry. The electric force according to him put the molecules of a solution in a state of tension. When the force was sufficiently strong to be opposed to the forces which bind the molecules together to allow the interaction with close molecules, the tension is eliminated by the migration from the particles along the lines from tension, different the atoms migrating each one from their with dimensions in opposite directions. The quantity of electricity which passed was clearly dependant.
Faraday establishes the two following laws of electrochemistry:
- the quantity of substance deposited on each electrode of an electrolytic cell is directly proportional to the quantity of electricity passing in the cell.
- the quantity of the various elements for a certain quantity of electricity is in connection with the molecular weight are equivalent.
William Sturgeon built an electrical motor in 1832 and invented the switch, a ring of roughcast metal which makes it possible the reinforcement spiralaire to maintain the contact with the electric current and which transforms the Alternative course into a D.C. current pulsated. It improved the voltaic battery and worked on the theory of thermoelectricity.
Hippolyte Pixii, one manufacturing of French instrument built the first Dynamo in 1832 and then the first dynamo of D.C. current by using the switch. It was the first use practices mechanical generator of current which used the concept shown by Faraday. John Daniell began experiments in 1835 with an aim of improving the voltaic battery in particular its problems to be an unstable and weak source of electric current. Its experiment gave remarkable results. In 1836, he invented the first pile in which hydrogen was eliminated in the generation from electricity. Danielle solved the problem of polarization. In its laboratory, it succeeds in combining a zinc amalgam of Sturgeon with mercury. Its version was one of the first batteries has two fluids which produced a source of reliable electric current for one long period of time.
William Grove produced the first room with combustion in 1839. It based its experiments on the fact that to send a current in water water divides into its components Hydrogène and Oxygène. Grove tried to make the reaction in the other direction, i.e. to combine hydrogen and oxygen to produce water and electricity. However, the combustion chamber term was invented by Ludwig Mond and Charles Langer in 1889, which tried to build the first apparatus using the air and industrial gas of coal. It off introduced also a powerful battery with the annual meeting of the British Association for the Advancement Science of 1839. The first pile of Grove consisted of zinc in a diluted sulphuric acid solution and from platinum in a nitric acid solution concentrated separates by a porous bridge. The pile could produce a current of 12 amps and 1.8 volt. This pile had the double voltage compared to that of the first Daniell pile. The pile of Grove to the nitric acid was the battery prefers American telegraph at its beginnings (1840-1860) because it offered a large current to the exit.
Whereas the traffic of the telegraph increased, it was noted that the Grove pile produced Dioxide nitrogen, a pollutant gas. Whereas the telegram became more complex, the need for a tension continues was critical and the apparatus of Grove was limited. During the American civil war, the pile of Grove was replaced by the battery of Daniel. In 1841, Robert Bunsen replaced the expensive electrodes out of turntable used in the battery of Grove by carbon electrodes. This led to a greater use of the Bunsen battery in the production of electric arc and electroplatine.
Wilhelm Weber developed in 1846 the electrodynamometer in which a power being on made turn a suspended ring has another ring which turns when a power is on to through. In 1852, Weber defines the unit of resistance the Ohm in the honor of Georg Ohm. The name of Weber is used for measuring units of the magnetic flux.
A German physicist Johann Hittorf concludes that the movement of the ions is the cause of the electric current. In 1853, Hittorf notices that certain ions move more quickly than others. This observation leads it to the concept of number of transport. Hittorf measured the changes of concentration in the electrolyzed solutions. From these results, it calculated the numbers of transport of many ions and in 1869, it published its results concerning the migration of the ions.
Projections of the end of XIXe and the XXe century
In 1869, Zénobe Gram builds the first dynamo, thus making it possible to create a D.C. current. Its generator includes/understands a circular reinforcement with much reel of wire.
Svante August Arrhenius published its thesis in 1884 Recherches on the galvanic conductibility of the electrolytes . From the result of his experiments, the author concluded that the electrolytes, once dissouts in water become with various degrees separate or dissociated in positive or negative ions. The degree of dissociation depends especially on the nature and the concentration of the substance in the solution. The ions were supposed to be the carriers of the electric current but also of a chemical activity. The relation between the number of ion and the number with a great dilution gives a quantity of an unquestionable interest
The race for the production of aluminum was gained in 1886 by Paul Héroult and Charles Martin Hall. The problem that met of many researchers by extracting aluminum was that the electrolysis of an aluminum salt in water produced Hydroxyde of aluminum. Hall and Héroult avoided this problem by dissolving Oxide aluminum in a new solvent, the Cryolithe (NaAlF).
Wilhelm Ostwald began its experimental work in 1875 on the law of action of the masses of water in relation to the chemical problem of affinity while insisting on electrochemistry and dynamic chemistry. In 1894, it gave the first modern definition of the Catalyze and deferred its attention on the catalyzed reactions. Ostwald is especially known for its contributions in the field of the electrochemistry with in particular of the studies on the electric Conductivité and the electrolytic dissociation of the organic acids.
Hermann Nernst developed the theory of the electromotive forces in the voltaic piles in 1888. It developed also methods to measure permittivities and it was the first to show that the solvents with a dielectric Constante high allow the ionization of chemical substances best. The first studies of Nernst in electrochemistry were inspire by the theory of Arrhenius on the dissociation which was the first to recognize the importance of the ions in solutions. In 1889, it elucidated the theory of the voltaic piles by considering the electrolytic pressure of dissolution the force of the ions coming from the electrode in the solution was opposed to the osmotic Pression ions dissouts. It applied the principles of thermodynamics to the chemical reactions taking place in a battery. In the same year, it showed that the characteristics of a produced current make it possible to calculate the free energy exchange in the reaction which produces this current. It establishes an equation known under the name of equation of Nernst which describes the relation between the tension of a pile and its properties.
In 1898 Fritz Haber published its book of study Electrochemistry: Grundriss DER technischen Elektrochemie auf theoretischer Grundlage theoretical bases of the technical electrochemistry, which was based on the course that it gave has Karlsruhe. In the foreword of its book, it expresses its intention to connect chemical research to the industrial processes. In the same year, it deferred the result of its work on oxidation and the electrolytic reduction in which it shows that the result of the reduction can be known if the tension with cathode is constant. In 1898, he explained the reduction of the Nitrobenzène by stage with cathode and this became the model for other reaction of similar reduction.
In 1909, Robert Andrews Millikan began a series of experiment to determine the load carried by only one electron. It started by measuring the race of a drop of water charged in an electric field. The result suggests that the load of the drop is a multiple of an electric elementary charge, but the experiment was not sufficient to convince. It obtained more precise results in 1910 with its famous experiment of the oil drop by which it had replaces the water drop which tended to evaporate too quickly.
February 10th, 1922, the Polarograph was born whereas, Heyrovský recorded the tension of current for a solution with 1 NaOH mol/L. Heyrovský correctly interpreted the increase in current between 1.9 V and 2V caused by the deposit of ion Na+ deposited and forming a Amalgame of sodium. With his colleague Masuzo Shikata it can afterwards built the first automatic instrument to record the tanks of polographe which became famous later like the Polarographie.
In 1923, Johannes Nicolaus Brønsted and Thomas Martin Lowry published primarily the same theory on the behavior of the Acide S and the Base S by using bases of electrochemistry.
In 1924, Rene Audubert and John Alfred Valentine Butler published independently the first approaches of a modern theory of overpressure which were to make it possible to give an account of the empirical law of Julius Tafel going back to 1905. In 1930, following work of its Hungarian pupil Tibor Erdey-Grùz (1902-1976), max Volmer formalized the electrochemical Cinétique slow systems by proposing the model of Butler-Volmer, which one owes the name with John Alfred Valentine Butler and with max Volmer. The law speed is given by the Relation of Butler-Volmer. In first approach one can treat an elementary stage of transfer of load by expressing the density of current to the electrode by:
International Society off Electrochemistry (ISE) was founded in 1949 by great names of thermodynamics and electrochemical kinetics (Marcel Pourbaix, John O' Mr. Bockris, Pierre Van Rysselberghe, Gaston Charlot…) following the CITCE (International committee of Thermodynamics and Electrochemical Kinetics).
The manufacture of the first sophisticated apparatus of electrophoresis in 1937 by Arne Tiselius (1902-1971), was worth with its inventor the Nobel Prize of Chemistry in 1948 for its work on the electrophoresis, used to separate proteins from the serums. The electrophoresis was developed in the years 1940 and 1950 and the technique was applied active the broadest proteins to the amino-acids and even for the inorganic ions.
During years 1960 and 1970, quantum electrochemistry was developed by Revaz Dogonadze and its pupils.
In 1959, Jaroslav Heyrovský (1890-1967) obtains the Nobel Prize of Chemistry for the invention of the Polarographie.
In 1983, Henry Taube (1915-2005) obtains the Nobel Prize of Chemistry for its work on the reactions of transfer of electrons in the metal complexes.
In 1992, Rudolph A. Marcus (1923-) obtains the Nobel Prize of Chemistry for its contribution to the theory of the transfer of load, which takes into account the energy of reorganization of solvent.
See too
Notes and references of the article
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