Electrochemical sensor for measuring the concentration of gases and the method of determining the concentration of gases by means of the sensor |
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IPC classes for russian patent Electrochemical sensor for measuring the concentration of gases and the method of determining the concentration of gases by means of the sensor (RU 2106621):
              
 Composite solid electrolyte for electrochemical sensors partial pressure of sulfur oxides / 2095800
The invention relates to analytical instrumentation and relates to a solid electrolyte for electrochemical sensors partial pressure of sulfur oxides
 Device for measuring the partial pressure of oxygen and the method of its manufacture / 2092827
The invention relates to the field of gas analysis, in particular, to a device for measuring the partial pressure of oxygen, containing a solid electrolyte and electrodes connected to the terminals for the signal is removed, the solid electrolyte is an oxide film of the material of the first electrode, in the form of metal matrix and placed inside the oxide film, the first outlet for removal of the signal connected to the metal matrix in the topic area, metal oxide, the second electrode is located on the surface of the oxide film and is made in the form permeable to oxygen conductive layer
 A device for gas analysis / 2091783
The invention relates to a device for gas analysis using electrochemical cells with solid electrolyte and can be used for control and regulation of process of burning all types of fuel
 Method of manufacturing electrode / 2029946
The invention relates to the field of gas analysis and gas-analyzing instrument engineering, in particular to the technology of fabrication of electrodes on the solid electrolyte of stabilized Zirconia, and can be used in the manufacture of electrochemical solid electrolyte sensor of oxygen concentration in various oxygen-containing gases, such as flue gases of power plants, the exhaust gases of internal combustion engines and so on
 Disposable electro-chemical indicators / 2258922
Continuous sheet of electrochemical indicators meant for detection of glucose in blood has multiple first and second electrodes, applied using stencil printing method in form of linear sequence on continuous sheet of flexible substrate material, reagent layer, applied by stencil method above said sheet so that said reagent covers at least one of first and second electrodes of each couple of electrodes, containing layer positioned above said reagent layer and said electrodes with forming of sample receipt chamber.
 Electrochemical mode of measuring of speed of chemical reactions / 2267120
The mode has phases: a reagent is fixed in electrochemical cell on minimum distance from the working electrode. At that the distance is such that transfer of electrochemically active substance from this field to the working electrode is diffusionally controlled, then the sample of the liquid is placed into the electrochemical cell in such a manner that the sample of the liquid is in the contact with the reagent. The working electrode and an antielectrode, the interaction of the component with the reagent is executed with receiving an electrochemically active substance; a potential between the working electrode and the antielectrode is applied. At that the potential is sufficient for electrochemical interaction of the electrochemically active substance on the working electrode, then the current of the electrochemical reaction on the working electrode is measured for getting measure of the speed of the chemical reaction.
 Nicrofluidic devices and methods of their preparation and application / 2423073
Group of inventions is intended for application in biological research. Microfluidic devices contain layer of photoresist, in which communicating with each other input chamber, optional reaction chamber and at least one detection chamber are located, located under photoresist layer support and located above photoresist layer cover. Devices additionally contain set of absorbing canals downstream with respect to the last detection chamber. In reaction chamber and detection chamber(s) placed are biogenic or immunoreactive substances. When liquid sample is introduced drop-by-drop into input chamber, sample liquid is drawn through said devices due to capillary action. Methods of detection include electrochemical detection, colorimetric detection and fluorescent detection.
 Method of measuring and control of oxygen concentration in exhaust gas of thermal power plant / 2519515
Gas sampling is carried out and the concentration of oxygen in the exhaust gas is determined by processing the information received using the computer. Gas sampling is performed using the sampling device, made of coaxial channels, connected with the end vortex chamber in which a sensor sensitive to oxygen is placed, and the determining of the oxygen concentration is performed by measuring the electromotive intensity of the sensor sensitive to oxygen and the continuous computer processing using the data based on a numerical solving the Nernst equation.
 Method of determining aniline, o-nitroaniline, and o- tolidine in air / 2247364
Electrodes of piezoelectric resonator are modified with menthol phenyl salicylate vaseline oil, recommended solvent being toluene, modifier film weight 5-20 μg, drying temperature 20-35°C, and drying time 40-48 h. The following gains in aromatic amine determination sensitivity are thus obtained: for aniline, from 282 to 368 Hz-m3/g; for o-tolidine, from 68 to 78 Hz-m3/g; for 9-nitroaniline, from 136 to 125 Hz-m3/g. Reductions in relative deviation are, respectively, 6.0 to 3.2%, 7.0 to 3.6%, and 6.0 to 4.3%, sensor response time is decreased by 5 times, regeneration time is decreased by 24 times, and aniline detection threshold is lowered from 0.84 to 0.11 Δ, g/m3.
 Sensor detection cell / 2247367
Device has reaction tank, made of non-rusting steel and provided with coat for thermostatting, lids with inbuilt holder for piezoquartz sensor, made of same material, piezoquartz sensor, input branch pipe, air output, reaction tank for detection with 100 sm3 volume. Inside said tank cassette perforated on both sides for samples of powder-like, hard substances and air ventilator for evening concentration of light substances at whole volume of cell are placed. Piezosensor is provided with moving cover, making it possible to actuate sensor with stabilized phase balance.
 Solid-electrolyte oxygen concentration detector and method of making the detector / 2298176
Method and detector can be used in metallurgy, power engineering, and chemical industry for measuring activity of oxygen in different media. Solid-electrolyte oxygen concentration detector has ceramic sensitive element placed hermetically inside case, comparison electrode and central electrode, both displaced inside cavity of ceramic sensitive element. Ceramic sensitive element is completely made of solid electrolyte in form of conjugated cylindrical element and part of sphere. External cylindrical part of ceramic sensitive element is connected with internal side surface of case by means of connecting material. Detector is additionally provided with plug made of metal oxide. Plug has opening and it overlaps cross-section of cavity of ceramic sensitive element. Comparison electrode is disposed in cavity formed by internal surface of ceramic sensitive element and surface of plug. Comparison electrode occupies at least part of cavity which part is turned to part of sphere. Free end of central electrode is withdrawn into space of comparison electrode through opening in plug. Electrical contact is provided between comparison electrode and lower part of central electrode. At least part of sphere of ceramic sensitive element protrudes out of case. Material of case, of ceramic sensitive element and of connecting material have similar temperature expansion coefficient. The materials have to be chemically resistant in relation to working medium. Bushing is soldered to internal part free part of case. Top part of central electrode protrudes out of bushing. Ring-shaped cavity between bushing and top part of central electrode is filled with dielectric material providing air-tightness of internal cavity of detector. Detector shows excellent operation under cyclical thermal shocks and at temperatures higher than 500C.
 Sensitive element of electrochemical sensor for carbon monoxide in gas mixtures / 2326375
Sensitive element of the electrochemical sensor for carbon monoxide in gas mixtures is made from a solid oxide electrolyte with polarised and non-polarised electrodes on its surface. The electrolyte is in the form of plates. The comparison non-polarised electrode is put on the surface of the electrolyte in form of a paste of silver oxide, while the operating polarised electrode is put on the surface of the electrolyte in form of a fine-dispersed platinum powder or palladium with a dope of up to 10% of the electrolyte powder. Both electrodes are baked, and the operating electrode is activated.
Method of making ruthenium electrodes for electrochemical sensor with solid electrolyte / 2342652
Present invention pertains to the technology of making electrodes on a solid electrolyte from stabilised zirconium dioxide, and can be used for making electrochemical solid electrolyte sensors for concentration of oxygen in different oxygen-containing gases. The essence of the invention lies in that, to make a ruthenium electrode, ruthenium is deposited on a degreased and activated surface of a solid electrolyte, through recovery of ruthenium from an aqueous solution of rutheniumhexamine (II) chloride, containing 0.2-0.4 g/dm3 ruthenium per 1 cm2 of the covered surface. Acidity of the solution is established by adding a solution of potassium hydroxide with concentration ranging from 0.36 g/l to 0.78 g/l to the reaction system. The process takes place at temperature of 170-210°C in an enclosed volume for 130-180 minutes.
 Method of determining temperature of measuring sensor / 2453834
In the method of determining temperature of a measuring sensor for measuring concentration of oxygen in gas mixtures, mainly in exhaust gases of internal combustion engines, the output voltage of a Nernst measuring element (12) which corresponds to oxygen concentration is analysed; temperature of the measuring sensor is changed such that it is equal to the working temperature using a heating device (50); internal resistance of the Nernst measuring element (12) is determined in a first temperature range and then used to determine temperature of the Nernst measuring element (12); internal resistance of the heating device (50) is determined in a second temperature range and then used to determine temperature Nernst measuring element (12).
 Solid electrolyte sensor for measurement of oxygen concentration in gases and molten metals / 2489711
Solid electrolyte sensor for measurement of oxygen concentration in gases and molten metals includes a solid electrolyte made in the form of a test glass, a reference electrode, an internal current collector from the reference electrode, a protective cover that is equipped with a contact ring and serves as an external current collector. According to the invention, the sensor is equipped with an additional measuring electrode with a current collector; the electrode is located in middle part of outside surface of the solid electrolyte glass, and the protective cover has through openings for passage of analysed gas to the measuring electrode surface.
 Sensor for determination of concentration of gaseous components in exhaust gases of internal combustion engines / 2541702
Electrolyte layer with thickness of 10 to 50 mcm is located in a sensor under the electrode located on the exhaust gas side; the above layer consists of zirconium oxide stabilised with scandium, and/or a mixture of zirconium oxide stabilised with scandium, and zirconium oxide stabilised with yttrium, and/or zirconium oxide stabilised with a mixture of scandium and yttrium. In order to minimise internal direct-current resistance of the sensor, layers of electrodes are made on the electrolyte so that they have geometrically maximum possible area of the surface.
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(57) Abstract: The invention relates to an electrochemical sensor for determining the concentration of a gas, comprising a housing, a measuring electrode containing a catalytically active material that has the ability to cause transformation of the sample gas, a counter-electrode containing a carbon material with the electrochemically active surface compounds that can reversibly oxidize, or to recover, and an electrolyte in contact with the measuring electrode and counter-electrode, while the carbon material in the counter-electrode has a specific surface area of at least 40 m2/, in Addition, the invention relates to a method of determining the concentration of gases by means of the sensor. 2 C. and 20 C.p. f-crystals, 2 Il. The invention relates to an electrochemical sensor for determining the concentration of gases such as hydrogen, carbon monoxide and silane, fluorine, chlorine, bromine, iodine, oxygen, sulfur dioxide, methane, ethane, ethylene, acetylene and other gases and to a method of determining the concentration of gases. The sensor can also be used in the manufacture of portable, self-powered and easily maintained prlja the environment are widely used in many fields, for example, for automatic control of technological processes, explosion protection, environmental control, and so on, These analyzers can be arranged on the basis of electrochemical sensors. For measuring and controlling the concentration of gases is known, various types of sensors. Known electrochemical sensor (Japan's bid 59-28258, CL G 01 N 27/46, 11.07.84), comprising a housing, a measuring electrode made of a catalytically active material, electrolyte and counter-electrode consisting of a mixture of coal and electrochemically active organic substances, for example, glorinha or Monomeric and polymeric phthalocyanine iron and cobalt. The electrochemically active substance acts as a catalyst in the electrochemical reduction of oxygen. in contact with the measuring electrode and counter-electrode. When applying to the sensor sample gas it is oxidized on the measuring electrode. On the counter-electrode in accordance with this recovering oxygen or specially supplied oxygen, provide active components (catalysts). When the sensor catalysts alternately reversed and oxidized. Both these reactions are not awsome, small and the reliability of the sensor, as can happen passivation of the surface of the counter-electrode the reduction products of oxygen and the diffusion of these reaction products to the measuring electrode. Another disadvantage of the sensor is the possibility of drying the liquid electrolyte. The use of a solid electrolyte in such a sensor is also difficult because of the need to create boundaries between the four phases of the "coal - catalyst - electrolyte oxygen". Another limitation of the use of the sensors mentioned type is based on the fact that such a sensor can operate for a long time only when the supply of oxygen, i.e., in oxygen-containing environments or when specifically implemented by the supply of oxygen. The use of liquid electrolyte reduces the mechanical resistance of the sensor. The basis of the invention is the development of electrochemical sensor for measuring the concentration of gases, with the greatest high reliability and long service life. The problem is solved in that in an electrochemical sensor for determining the concentration of a gas, comprising a housing, a measuring electrode containing catalytically and the containing carbon material with the electrochemically active surface compounds which can reversibly oxidize, or to recover, and an electrolyte in contact with the measuring electrode and counter-electrode, according to the invention, the carbon material in the counter-electrode has a specific surface area of at least 40 m2/, In the sensor according to the invention, the carbon material in the counter-electrode may have a specific surface area of 1000 - 3000 m2/, In the sensor according to the invention, the carbon material in the counter-electrode may have a specific surface area of 1000 - 3000 m2/, The catalytically active material of the measuring electrode is a material which, on the one hand, must be resistant to the electrolyte and, on the other hand, catalyzes the transformation of the sample gas. In the sensor according to the invention, as a catalytically active material in the measuring electrode is used plate, carbon or gold. The measuring electrode can be totally or partially consist of a catalytically active material, i.e., can be used, for example, a platinum wire or a platinum mesh or only covered with a platinum electrode. In the sensor according to the invention, as the carbon alterntively surface compounds. The electrochemically active compounds on the surface of the counter-electrode to the question, as a rule, oxygen-containing compounds, formed on its surface during the process of obtaining a carbon material. Such compounds are reversibly oxidized and recovering. In the sensor according to the invention, surface compounds carbon material may contain substances such hydroquinone/quinone. In the sensor according to the invention, the electrolyte may be placed in a solid matrix. In the sensor according to the invention, the sensor housing can be made of the inlet for gas to be detected in the gas space situated in contact with the measuring electrode, and the holes for the electrode contacts. In the sensor according to the invention, between the measuring electrode and counter-electrode can be located permeable to ions separator. In the sensor according to the invention, between the gas space and the measuring electrode can be located gas-permeable diffusion membrane. In the sensor according to the invention, the electrolyte contains ions formed by ionization of gas Isny electrode serves to maintain, basically, the constant potential of the measuring electrode (i.e., in the range of the limiting current diffusion). The reference electrode may be made of a catalytically active material, for example, from W material as the measuring electrode. The reference electrode must have a large surface to prevent polarization. It is placed in the electrolyte, for example, between the measuring electrode and counter-electrode. When using such a sensor with three electrodes on the measuring electrode and counter-electrode undergoing the same processes as that of the sensor with only two electrodes. The sensor according to the invention may contain an additional electrode. The sensor according to the invention, can contain multiple measuring electrodes. The use of such additional electrode provides regeneration of the sensor during operation due to the discharge of the counter-electrode. Between the counter-electrode and an additional electrode is applied a voltage which is necessary for measuring the concentration of the sample gas. The second measuring electrode based on the same principle as the first. From the choice of the catalytically active material is what will turn the gas. While it is preferable, if one measuring electrode, oxidation of the sample gas and the other recovery other gas. In this case, when the first measuring electrode, the counter-electrode is charged, and when the second measuring electrode, the counter-electrode are simultaneously discharged. This leads to a significant increase in service life electrochemical sensor, because when alternating and/or simultaneous operation of the measuring electrodes and the counter-electrode is not being charged. The second measuring electrode is thereby simultaneously for measuring the concentration of a second gas, and as an additional electrode for discharge of the counter-electrode. The sensor according to the invention may contain as the electrolyte, a solid electrolyte consisting of polymerizate, which is included in the electrolyte solution. In the sensor according to the invention, the solid electrolyte can be produced by polymerization of at least one monomer, mixed with liquid electrolyte. In the sensor according to the invention, the solid electrolyte can be produced by polymerization of a mixture of methacrylate choice, according to the invention, the acid can be used sulfuric acid, triftormetilfosfinov, phosphoric acid or their mixture. The problem is solved by a method for determining the concentration of one or more gases as electrochemical sensor using the sensor according to the invention. With the method according to the invention it is possible to analyze any gases, provided that they can turn on a catalytically active measuring electrode. Examples of suitable gases are hydrogen, fluorine, chlorine, bromine, iodine, oxygen, sulfur dioxide, silane, carbon monoxide, nitrogen dioxide, methane, ethane, ethylene and acetylene. When using two measuring electrodes simultaneous analysis of two different gases (e.g. hydrogen and oxygen). In the method according to the invention determines the concentration of a gas selected from the group consisting of hydrogen, oxygen, carbon monoxide and silane. In the method according to the invention an electrochemical sensor attached to the outer conductive circuit between the electrodes of the sensor set passing the external potential and the external conductive circuit measure the t the t the concentration of hydrogen, and use the sensor containing the electrode of the plate, the counter-electrode of activated carbon with a specific surface area of 1,000 - 1,700 m2/g and an electrolyte on the basis of a strong mineral acid, with external potential set about 0.3 Century In the method according to the invention after a set duration of operation of the sensor is again recovered by a change in the polarization of the electrodes by application of an external voltage. In Fig. 1 in simplified schematic form shows a vertical section of the first version of the sensor according to the invention; Fig. 2 is a vertical section of a second variant of the sensor according to the invention. As shown in Fig. 1, the sensor includes a housing 1 of an inert dielectric material such as Teflon or plexiglass. Dimensions of the case may be, for example, 20 mm in diameter and 40 mm in height. In the cylindrical side wall 1a of the case is made two holes for pins 2, 6 electrodes. Contact wire 2 that serves to ready the sensor for shielding the counter-electrode, is placed on the bottom 1b of the housing and threaded through one of the holes. In the case insert the counter-electrode 3, and the surface of the counter-electrode 1000 - 1700 m2/g, i.e., its porosity is very high. The counter-electrode is impregnated with the liquid electrolyte. An electrolyte consisting of a mixture of the polymerized monomers, e.g. methyl methacrylate, the polymerization initiator, for example, azo-bis(isobutyronitrile), and an ion-conductive substance (for example, in the case of H2sensor acid) is poured into the case and leave for about 30 minutes During this time, the liquid penetrates into the pores of the counter-electrode. Then press press punch and the body with the counter-electrode is placed in the heating device. In the heating device at a suitable temperature (for example, 120oC) for a suitable time (e.g., 2 h) there is a complete prepolymerisation, causing an increase in the viscosity of the electrolyte. The degree of polymerization can be controlled by external conditions (time, temperature and pressure as necessary), the concentration of initiator and, if necessary, additives inhibitor of polymerization. Due to prepolymerisation in the housing formed "unit" consisting of a counter-electrode, electrolyte and the contact wire. After this the case with protivoelektrodom block is extracted from the heating device and the unit put separate the pour preferably of a porous polymeric material, resistant to the applied electrolyte, for example, from polypropylene. Then on the separator put the measuring electrode 5 of the catalytic active material. The measuring electrode can be manufactured, for example, in the form of a grid made of platinum with a thickness of about 50 μm and a diameter corresponding to the diameter of the separator. Connected with the measuring electrode contact wire 6 is passed through one of the holes in the housing. The separator and the electrode presoviet with protivoelektrodom unit, resulting in a separator impregnated with electrolyte, and the electrode moist. Prepared in this way the sensor is placed again in the heating device, which is now in suitable conditions (for example, at a temperature of 110oC for one hour) is complete polymerization of the electrolyte. After that, the electrode is put gas-permeable diffusion membrane 7, preferably produced from a polymer, such as Teflon. The membrane should fit snugly to the electrode. Worn on the body cover 8 presses the diaphragm to the measuring electrode. This cover can be manufactured, for example, from the same material as the housing. The cover I have is ment for lines, through which the gas stream can be fed to the sensor and to withdraw from him. Between the cover 8 and the membrane 7 is the gas space 11. Cover the membrane and the housing is firmly connected, for example glued. Thus the counter-electrode is in a sealed chamber, a closed casing and separator. Contact wire attached to the external conductive circuit (not shown) containing the ammeter and voltage source. Another possible variant of the sensor contains instead of a solid electrolyte liquid. In this case, the counter-electrode is impregnated with electrolyte, and then in case you invest your hard porous membrane, for example, from the same material as the housing. On this membrane, as described above, put the separator and the electrode. The polymerization is carried out in the heating device. Otherwise, the manufacturer of the sensor spend as sensor with solid electrolyte. When the sensor of the gas mixture containing the analyzed gas, through holes 9, 10 enters the gas space 11 and diffuses through the diffusion membrane 7 to the measuring electrode 5. The membrane ensures a stable supply of the gas mixture by measuring the External voltage source, to which is attached the contact wire provides the necessary potential difference relative to the counter-electrode 3. As due to the high capacity of the counter-electrode potential changes very slowly and the potential difference is maintained constant, the potential of the measuring electrode also varies very slowly. The potential of the measuring electrode lies in the limiting current range of turning gas. The gas that reaches the measuring electrode, is subjected to transformation, ions formed in the electrolyte in the process of transformation, migrate to the surface of the counter-electrode. This causes current to flow in the external conductive circuit. The separator prevents electrical contact between the two electrodes, however, ignores ions. Due to the bias charge to the counter-electrode is charging the electric double layer at the boundary of the electrolyte and counter - electrode. ions adsorbed on the surface of the counter-electrode. The processes in the electric double layer, is described in detail in the book. Damascus B. B. and Petri O. A. - Introduction to electrochemical kinetics, 1975, High school, M., S. 105 - 130. When charging of the double layer potential of the counter-electrode is ocessi reversible oxidation or chemical recovery of surface compounds. These processes are described in the book Tarasevich, M. R. electrochemistry of carbon materials, 1984, Nauka, M., S. 253. The current in the outer conductive circuit is proportional to the concentration of the gas, turning on the measuring electrode with the formation of ions. When the current flows over time increases the charge of the electric double layer and changes the potential of the counter-electrode. Valid change of potential depends on the electrochemical stability of the used electrolyte. If the potential of the counter-electrode higher than the potential of the decomposition of the electrolyte, the current in the external conductive circuit is no longer proportional to the gas concentration. This leads to a distortion determination of gas concentration, i.e. the concentration of gas is possible, while the potential of the counter-electrode lies within acceptable limits. The service life of the sensor corresponds to the time during which the change of potential of the counter-electrode does not exceed the maximum allowable change. Below is the calculation of the service life of the sensor. The capacity C of the double layer corresponds to the charge qcthat must be fed to a counter-electrode to change its capacity by one unit. . Thou tcthat would change the potential of the counter-electrode at :. If within the maximum allowable change of potential and if there is only charging of the double layer, the lifetime of the sensor . The capacity of the double layer is proportional to the size S of the surface of the counter-electrode (C = KcS, where Kc- a constant of proportionality), and formula (3) gives: . On the counter-electrode flow, moreover, the reversible processes of recovery or oxidation chemical surface compounds. These processes (Faraday processes) are described by the laws of Faraday: qfKf= m (5) , where m - converted amount of the substance; Kf- a constant of proportionality; qfthe amount of charge consumed during the recovery or oxidation. The amount of charge qfdepends on the current I and the time within which the proceeds of the Faraday processes: qf= I x tf< / BR> This gives: I tfKf= m (6) . On the counter-electrode are various surface connections, which correspond to different values of the potential recovery or oxidation. These values lie in let Haradok above, than the capacity of the double layer. Therefore, the change of potential of the counter-electrode when restoring or oxidation of the surface of the connection runs much slower than when the charging of the double layer. In some areas of the curve of the charging potential of the applied amount of charge), the potential remains for some time unchanged. Faraday process lead to the fact that the potential of the counter-electrode remains in the valid range for much longer and the lifetime of the sensor will increase greatly. After full recovery or oxidation of a specific surface connection potential begins again to change according to equation (2), until it reaches the value at which you want to restore or more oxidized surface connection. The potential of the counter-electrode varies, therefore, according to equation (2) with interruptions caused by the Faraday processes. For surface compounds i are really: I tfiKfi= mi(7) where tfithe time for recovery or oxidation of the surface of the compound i; Kfi- a constant of proportionality to conduct the time, during which the flow of the Faraday processes, the following: . The number of surface compounds is proportional to the surface S of protivoelektrodom: mi= KiS (9) . This gives: . The lifetime t of the sensor corresponds to the sum of: t = tc+ tfi. This gives: . The service life of the sensor is greater, the greater the surface of the counter-electrode, a valid change of potential, the number of surface compounds and less than the current flowing through the electrode. Amperage can accordingly be adjusted by selecting the material, design and position of the membrane 7 and the measuring electrode 5. These parameters should be chosen so as to ensure the required accuracy of measurement and the corresponding measurement range. In most cases, the current lies in the range of μa. Valid change of potential of the counter-electrode depends on the electrochemical stability of the electrolyte. For applied solid electrolyte this change is 0,4 - 0,6 Century The area of the counter-electrode when the specific surface area of activated charcoal 1000 - 1700 m2/g and the mass of the counter-electrode about the Loya (several thousand farads (f)), for example, activated carbon with a specific surface area of 1500 m2/g specific capacity is 400 f/, For the counter-electrode 10 g of activated carbon, the admissible change of the potential of 0.4 V and a current of 20 μa according to equation (3) follows: . The amount of chemical surface compounds can be determined. In M. R. Tarasevich the ("electrochemistry of carbon materials, 1984, Nauka, M., S. 35), the maximum oxygen content in the activated carbon is 0.5 to 3 mmol/g, the Oxygen is on the surface of activated carbon, inter alia, in the form of compounds, for example, quinone/hydroquinone, which has been proved experimentally defined and known in the literature (catalogue company HEK, Japan, 1982) reversibility of electrochemical processes on the surface of activated carbon used in the range of the potential. Assuming that in such compounds contains about half the amount of oxygen, the amount of these compounds can be calculated as a maximum of about 3 mmol/g of activated carbon (functional group quinones contains one atom of oxygen). Because recovery or oxidation of the functional group of compounds of the type quinone/hydroquinone associated with the transfer of one electron to the = 26,8 A PM mol-13 10-3mol/g = 0,08 And h/g Of qf= tf1 follows: , i.e. for the above example (when the mass of the electrode 10 g): . According to equation (11) is valid: t = tc+ tf= 20000 + 40000 = 60000 hours i.e. more than 6 years. If the specific surface area of coal is 2000 m2/g, from this evaluation, the service life is about 80000 hours, i.e. about 9 years. The use of activated carbon with higher specific surface increases the service life of the sensor, however, is associated with high costs. Maximal known specific surface area of activated carbon is about 3000 m2/g (Alvin B., Steel C. - Bearers and deposited catalysts. Theory and practice, M.: Chemistry, 1991, S. 111). The use of activated carbon with a specific surface area of 40 to 1000 m2/g provides the service life of the sensors corresponding to the service life of the majority of known sensors (about 1 year). For example, a counter-electrode of activated carbon with a specific surface area of 40 m2/g and a weight of 50 g has a lifespan of 8,000 hours (less than 1 year). Electrochemical properties of chemical surface compounds exclude the possibility of passivation PA. The electrochemical reaction involving the chemical surface compounds are reversible. The known system, the so-called super capacitor (catalogue company HEK, Japan, 1982 ), contains two electrodes of activated carbon and is used as a capacitor with very high capacitance. In this system, both electrodes run the same processes as described above for protivoelektrodom sensor Due to the reversibility of electrochemical processes at the electrodes of activated carbon and, therefore, an unlimited number of cycles of charge-discharge the capacitor has an unlimited lifespan. Without changing the parameters has been reached 1500 cycles. In accordance with literature and experimental data sensors according to the invention can but the end-of-life to regenerate by a change in the polarization of the electrodes by application of an external voltage. Then on both the sensor electrode reactions proceed, reverse the above-described electrochemical reactions. In the hydrogen sensor, for example, with a change of polarization on the measuring electrode of the proton electrolyte formed hydrogen (2H++ 2e-H2). On protivorehie sensor or restore corroded chemical surface compounds. If the amount of charge passing in the opposite direction, corresponds to the quantity of charge passed during the time of the sensor, the counter-electrode is in the initial state relative to the charge and potential. On the measuring electrode during the charging process produces a quantity of hydrogen corresponding to the converted when the amount of hydrogen. The sensor returns to its original state and can again be used to determine the hydrogen concentration. Since the processes on the measuring electrode in the hydrogen sensor is reversible, the number of cycles "work-regeneration" theoretically unlimited, i.e., theoretical lifetime of the sensor is also unlimited, if he is constantly regenerated. As a counter-electrode can withstand at least 1500 cycles "work-regeneration", the possibility of regeneration of the sensor is determined by measuring the electrode. For example, the number of cycles for the oxygen sensor is about 50. The possibility of regeneration of the sensor significantly increases the service life compared with all known electrochemical gas sensors. In the sensor according to the invention therefore preferably, if the electronic is the use of such electrolyte composition and concentration are virtually unchanged. For example, the electrolyte containing the protons used in the sensor of hydrogen (H22H++ 2e-), the electrolyte containing fluorine ions, in the sensor of fluorine (F2+ 2e-2f-), the electrolyte containing ions of chlorine) chlorine sensor (C2+ 2e-2C-). Can also be used for other electrolytes, for example, the electrolyte containing F-ions, to determine the concentration of chlorine. This leads, however, to change the composition of the electrolyte in the gas conversion and may affect the service life of the sensor and the distortion of the signals due to changes in the equilibrium potential of the measuring electrode. In Fig. 2 shows a second embodiment of the sensor according to the invention, which, together with the measuring electrode and counter-electrode contains additional electrode. In this case, the regeneration of the sensor may occur during its operation. The position of Fig. 2 corresponds to the position of Fig. 1. The sensor housing of Fig. 2 has a back wall (1b in Fig. 1). Instead, the sensor includes an additional electrode 12 separated by the separator 13 from the counter-electrode. The additional electrode may be made of a catalytically active material (n is electrode. When the sensor between the counter-electrode and an additional electrode applied voltage. Concentration measurement of gas flows in the same way as described for the sensor without additional electrode. Additional electrode provides regeneration of the sensor during operation. For this purpose, the voltage between the additional electrode and the counter-electrode is chosen so that the counter-electrode proceeded processes, reverse the process during normal operation of the sensor (with regard to the measuring electrode). If, for example, a counter-electrode acting on the measuring electrode as a cathode, so that when the sensor processes are charging the electric double layer, the counter-electrode is relatively additional electrode as the anode, so that the simultaneous discharge of the electric double layer and oxidation of surface compounds on the counter-electrode. On the additional electrode is in this electrochemical reaction, for example, the recovery of oxygen from air or hydrogen gas from the electrolyte. The rate of these processes depends on the voltage between the additional electrode and the counter-electrode. The voltage optimally you britnee direction) the average current flowing between the measuring electrode and counter-electrode. Thus when working simultaneously charging and discharging of the counter-electrode. This leads to a significant increase in service life of the sensor. This lifetime is determined valid by changing the potential of the counter-electrode. Through the use of an additional electrode potential of the counter-electrode is changed much more slowly. Service life of such a sensor with an additional electrode is limited by possible changes in the composition of the electrolyte during the electrochemical reactions occurring at the measuring electrode and counter-electrode. In some cases, however, the service life of such a sensor is theoretically unlimited, for example, if the sensor of hydrogen on the additional electrode is hydrogen gas, the composition of the electrolyte does not change. In such a flow sensor the following reactions: - on the measuring electrode: H22H++ 2e-< / BR> the additional electrode: 2H++ 2e-H2< / BR> By using an additional electrode can increase the service life of the sensor and/or to reduce the size of the sensor (the number of activated carbon) without tricategories and tested. The sensor housing was made of polyethylene. The counter-electrode was made of a fabric of activated carbon with a thickness of 30 μm and a specific surface area of 1500 m2/, a counter-electrode had a diameter of 20 mm, the Total weight of the electrode was 2.3, the electrode was made of platinovoi grid and had a diameter of 19 mm, a Separator was made of polypropylene. Used liquid electrolyte (38% sulphuric acid). As diffusion membranes used polietileno film thickness of 20 μm. The sensor had an inner diameter of 24 mm, a height of 20 mm and a weight of 3, the external conductive circuit included ammeter and voltage source. Valid change of potential of the counter-electrode in the electrolyte were 0.4 Century For aeration was applied gas mixture of hydrogen and nitrogen. The concentration of hydrogen was known and amounted to 48%. When the concentration of H24% and the polarization voltage +0.3 V (measuring electrode relative to the counter-electrode) current was 10 μa. When the specific surface area of activated charcoal 1500 m2/g specific capacity was about 400 f/g, which according to the equations(3), (11), (13) allows you to determine service life: < / BR> i.e. more than 3 years. Next was made is polymethylmethacrylate (plexiglass). For the counter-electrode applied powder activated carbon with a specific surface area of more than 1500 m2/year Mass of the counter-electrode was 1.8, the Solid electrolyte was produced from a mixture of methacrylate as a monomer, azobis(isobutyronitrile) as an initiator and sulfuric acid (38%) by polymerization at elevated temperature. The measuring electrode, the separator and the membrane were fabricated as described above sensor. Valid change of potential of the counter-electrode used in the solid electrolyte was 0.6 Century, When the hydrogen concentration of 4% and the polarization voltage +0.3 V current was 12 mA. The lifetime of the sensor was: , i.e. about 2.5 years. After 500 hours of aeration was carried out regeneration of the sensor by the change of direction of the polarization voltage. Example 2. Was manufactured and tested sensor according to the invention with a measuring electrode, a counter-electrode and a reference electrode for measuring the concentration of carbon monoxide. The sensor contains a solid electrolyte made from a mixture of methyl methacrylate as a monomer, azobis(isobutyronitrile) as an initiator and phosphoric acid through the platinum black Teflon membrane. The reference electrode was located between the measuring electrode and counter-electrode was separated from them by a separator. The counter-electrode and the separator were made as in example 1. Valid change of potential of the counter-electrode was used in the solid electrolyte 0,4 Century, the Potential of the measuring electrode is maintained constant relative to the potential of the reference electrode through a scheme of voltage stabilization. When the applied potential difference between the measuring and reference electrodes is 0.1 V and the concentration of CO 30 PM per million in the air current of the sensor was about 1.5 μa. The lifetime of the sensor was calculated in accordance with example 1 as follows: , i.e., more than 20 years. Example 3. Was manufactured and tested sensor according to the invention with an additional electrode. The sensor contains a measuring electrode, a counter-electrode and a solid electrolyte made as in example 2. As an additional electrode used platinum mesh. When the applied potential difference between the measuring electrode and counter-electrode -0,25 In and the hydrogen concentration of 200 million hours in the external conductive circuit runs cathode (relative to the counter-electrode) Toko proceeded anode (relative to the counter-electrode) current 550. This sensor is charging and the discharging of the counter-electrode. The electrolyte composition is not changed, so that the service life of such a sensor is theoretically unlimited. Example 4. Was manufactured and tested sensor according to the invention with two measuring electrodes. One of them was determined that the concentration of hydrogen and one oxygen. The sensor consisted described in example 2, a solid electrolyte. As diffusion membranes used a polyethylene film of thickness 20 μm for measuring hydrogen electrode and 30 μm for oxygen. With an applied voltage of +0.3 V between the hydrogen measuring electrode and counter-electrode and the concentration of H2400 million hours in the external conductive circuit flowed a current of 4.5 mA. When the voltage of-0.2 In between the oxygen measuring electrode and counter-electrode and an oxygen concentration of about 20.8 per cent in the external conductive circuit flowed a current of about 5 μa. Thus occurs simultaneously charging and discharging of the counter-electrode. Effective current, causing the charging of the counter-electrode, consists of the difference between these two currents and is 5 µa - 4.5 μa = 0.5 μa, as associated with the oxidation of H2and vosstanovlenie is 5. The electrolyte according to the invention may contain, instead of oxygen, the mixture of acids. Was manufactured and tested two-electrode sensor for detecting the concentration of carbon monoxide. The solid electrolyte was produced from a mixture of methyl methacrylate as a monomer, azobis(isobutyronitrile) as an initiator and triftoratsetata and phosphoric acid by polymerization at elevated temperatures. This electrolyte has a very low hygroscopicity, so that it is suitable, in particular, for sensors with porous diffusion membrane. Valid change of potential of the counter-electrode is for this electrolyte of 0.2 C. 1. Electrochemical sensor for determining the concentration of a gas, comprising a housing, a measuring electrode containing a catalytically active material that has the ability to cause transformation of the sample gas, a counter-electrode containing a carbon material with the electrochemically active surface compounds that can reversibly oxidize, or to recover, and an electrolyte in contact with the measuring electrode and counter-electrode, wherein the carbon material in protovale what about the carbon material in the counter-electrode has a specific surface area of 1000 - 3000 m2/, 3. The sensor under item 1 or 2, characterized in that the catalytically active material in the measuring electrode using platinum, carbon or gold. 4. The sensor PP.1 to 3, characterized in that the carbon material in the counter-electrode to the use of porous activated carbon with oxygen-containing electrochemically active surface compounds. 5. The sensor under item 4, characterized in that the surface of the connection of the carbon material contains substances such hydroquinone/quinone. 6. The sensor PP.1 to 5, characterized in that the electrolyte is placed in a solid matrix. 7. The sensor PP.1 - 6, characterized in that the sensor housing is made of the inlet for gas to be detected in the gas space situated in contact with the measuring electrode, and the holes for the electrode contacts. 8. The sensor PP.1 to 7, characterized in that between the measuring electrode and counter-electrode is permeable to ions separator. 9. The sensor under item 7 or 8, characterized in that between the gas space and the measuring electrode is gas-permeable diffusion membrane. 11. The sensor PP. 1 to 10, characterized in that it contains a reference electrode. 12. The sensor PP. 1 - 11, characterized in that it contains an additional electrode. 13. The sensor PP.1 - 12, characterized in that it contains several measuring electrodes. 14. The sensor PP.1 - 13, characterized in that it contains as the electrolyte, a solid electrolyte consisting of polymerizate, which is included in the electrolyte solution. 15. The sensor under item 14, characterized in that the solid electrolyte is made by polymerization of at least one monomer, mixed with liquid electrolyte. 16. The sensor under item 15, wherein the solid electrolyte is made by polymerization of a mixture of methyl methacrylate as a monomer, azo-bis (isobutyronitrile) as an initiator and an acid or mixture of acids. 17. The sensor under item 16, characterized in that the acid using sulfuric acid, triftormetilfullerenov, phosphoric acid or their mixture. 18. The method of determining the concentration of one or more gases using an electrochemical sensor, wherein the electrochemical sensor using the sensor consisting of hydrogen, oxygen, carbon monoxide and silane. 20. The method according to p. 18 or 19, characterized in that the electrochemical sensor is attached to the outer conductive circuit between the electrodes of the sensor set suitable external potential and the external conductive circuit to measure current, proportional to the concentration of the sample gas. 21. The method according to p. 20, characterized in that to determine the concentration of hydrogen, and use the sensor containing the measuring electrode made of platinum, a counter-electrode of activated carbon with a specific surface area of 1,000 - 1,700 m2/g and an electrolyte on the basis of a strong mineral acid, with external potential set about 0.3 Century 22. The method according to PP.18 to 21, characterized in that after a predetermined duration of operation of the sensor is again recovered by a change in the polarization of the electrodes by application of an external voltage.
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