JP2010185855A - Method and apparatus for stabilizing constant-potential electrolytic gas sensor, manufacturing method of same, gas analyzer, and constant-potential electrolytic gas sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for stabilizing constant-potential electrolytic gas sensors and capable of stabilizing the output sensitivity of the constant-potential electrolytic gas sensors in a short time without affecting a working pole, a counter pole, or further a reference pole which are involved in the detection of electrode reaction at measurement and to provide a manufacturing method of constant-potential electrolytic gas sensors, a gas analyzer, and a constant-potential electrolytic gas sensor. <P>SOLUTION: In the method for stabilizing constant-potential electrolytic gas sensors having two poles of a working pole and a counter pole or three poles of a working pole; a counter pole, and a reference pole in an electrolytic solution housing part housing an electrolytic solution to detect an electrolytic current of a gas to be detected at the working pole, a voltage is applied between a process electrode provided in the electrolytic solution housing part separately from the working pole, the counter pole, or the reference pole and the working pole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention is, for example, a potentiostatic electrolysis used for measuring sulfur dioxide (SO ₂ ), nitrogen oxide (NOx), carbon monoxide (CO), etc. in exhaust gas from waste incinerators, boiler furnaces, engines, etc. The present invention relates to a method and apparatus for stabilizing a gas sensor, a method for manufacturing a constant potential electrolytic gas sensor, a gas analyzer, and a constant potential electrolytic gas sensor.

Conventionally, for example, a test gas such as sulfur dioxide (SO ₂ ), nitrogen oxide (NOx), and carbon monoxide (CO) contained in an incineration exhaust gas incinerated with waste or the like is detected and the amount thereof is measured. There is a constant potential electrolytic gas sensor used for the above.

  The constant potential electrolytic gas sensor has a working electrode that detects a test gas, a counter electrode that allows current to flow between the working electrode, and a reference electrode that controls the potential of the working electrode. These working electrode, counter electrode, and reference electrode are arranged in a space partitioned by a porous gas diffusion membrane (gas permeable diaphragm), and this space is filled with an electrolytic solution. The test gas passes through the gas-permeable diaphragm, dissolves in the electrolyte, and comes into contact with the working electrode. The test gas is electrolyzed at the working electrode in which the potential difference from the reference electrode is kept constant, and the electrolytic current flowing according to the electrochemical reaction between the working electrode and the counter electrode is measured. The constant potential electrolytic gas sensor is configured such that the electrolysis current value is proportional to the concentration of the test gas, and by measuring this electrolysis current value, it can be converted to the concentration of the test gas.

  As described above, the constant potential electrolytic gas sensor measures the electrolytic current accompanying the oxidation reaction or reduction reaction when the gas is electrolyzed at a constant potential, but maintains an equilibrium state in which the reaction between the working electrode and the counter electrode is stable. Under conditions, an electrolysis current proportional to a certain gas concentration is obtained.

  In the initial state when the user uses the potentiostatic gas sensor for the first time, the surface state of the working electrode and the counter electrode in the electrolytic cell (electrolyte container) is not uniform, so there is variation in output and constant A long time aging is required until an output sensitivity of 1 is obtained.

  In order to shorten this time, when an applied voltage is not required, that is, when the electrolytic potential of the test gas is 0 mV, a short aging period is used to provide a fixed aging period before the measurement, such as using a short plug. It is possible to make the surface state between the counter electrodes uniform. However, it is desirable to further reduce the time taken to stabilize the output.

  On the other hand, when an applied voltage is required, this method cannot be applied when the electrolysis potential of the test gas is not 0 mV. Therefore, aging is performed for a very long time (for example, 24 hours to 150 days) before use. It is necessary to start measurement after it becomes stable.

  In addition, when the constant potential electrolytic gas sensor is used for a long time, the output gradually decreases. Therefore, in order to obtain a certain output sensitivity, for example, in Patent Document 1, a current in the same direction as the electrolytic current of the measurement target gas is generated in the working electrode, and the potential at the time of measurement (first It is described that sensitivity recovery is performed by applying a potential (second potential) higher than (potential 1).

JP-A-2005-127828

  It is conceivable to use the sensitivity recovery method of the constant potential electrolytic gas sensor described in Patent Document 1 as a method for stabilizing the output sensitivity of the constant potential electrolytic gas sensor.

  However, in this case, a voltage is applied between the working electrode and the counter electrode in the stabilization process, which may affect the electrode reaction when detecting the electrolysis current of the test gas. In other words, in order to stabilize the interface state of the working electrode, it is considered that when the voltage is applied between the working electrode and the counter electrode using the counter electrode or the reference electrode, the surface state of the counter electrode or the reference electrode disappears from the natural state. Therefore, it is not desirable to apply a voltage between the working electrode using these.

  Therefore, an object of the present invention is to stabilize the output sensitivity of the potentiostatic gas sensor in a shorter time without affecting the working electrode, counter electrode, and reference electrode involved in the detection of the electrode reaction during measurement. The present invention provides a stabilization method and apparatus for a constant potential electrolytic gas sensor, a method for manufacturing a constant potential electrolytic gas sensor, a gas analyzer, and a constant potential electrolytic gas sensor.

  The above object is achieved by the method and apparatus for stabilizing a potentiostatic gas sensor, the method for producing a potentiostatic gas sensor, the gas analyzer, and the potentiostatic gas sensor according to the present invention. In summary, the first aspect of the present invention has two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode in an electrolytic solution container that stores the electrolytic solution. A method for stabilizing a constant-potential electrolytic gas sensor that detects an electrolytic current of a gas, wherein the working electrode, a counter electrode, or a reference electrode provided separately from the working electrode, the counter electrode, or the reference electrode in the electrolytic solution housing portion This is a method for stabilizing a constant potential electrolytic gas sensor, characterized in that a process of applying a voltage is performed.

  According to the second aspect of the present invention, the working electrode and the counter electrode, or the working electrode, the counter electrode, and the reference electrode, are provided in the electrolytic solution storage unit that stores the electrolytic solution. A method for producing a constant potential electrolytic gas sensor for detecting an electrolysis current, the step of providing a processing electrode separately from the working electrode, the counter electrode or the reference electrode in the electrolyte container, the processing electrode and the working electrode, And a step of performing a process of applying a voltage between the two. A method for manufacturing a constant potential electrolytic gas sensor is provided.

  According to the third aspect of the present invention, the working electrode and the counter electrode, or the working electrode, the counter electrode, and the reference electrode are provided in the electrolytic solution storage unit for storing the electrolytic solution. A stabilization apparatus for a constant potential electrolytic gas sensor for detecting a current, wherein a voltage is applied between a processing electrode and a working electrode provided separately from the working electrode, the counter electrode, or the reference electrode in the electrolyte container. There is provided a stabilizing device for a potentiostatic gas sensor, characterized by having a voltage applying means for applying, and performing the above-described processing in the stabilization method of the present invention.

  According to the fourth aspect of the present invention, there are two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode, in the electrolytic solution container that stores the electrolytic solution, and electrolysis of the test gas at the working electrode. A gas analyzer including a constant potential electrolytic gas sensor for detecting a current, wherein the constant potential electrolytic gas sensor includes a processing electrode in the electrolyte solution storage unit separately from the working electrode, the counter electrode, or the reference electrode. And measuring means for measuring the electrolytic current of the test gas at the working electrode detected by the constant potential electrolytic gas sensor, and voltage applying means for applying a voltage between the processing electrode and the working electrode The gas analyzer is characterized in that the processing in the stabilization method of the present invention can be performed.

  According to the fifth aspect of the present invention, there are two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode, in the electrolytic solution container that stores the electrolytic solution, and electrolysis of the test gas at the working electrode. A constant potential electrolytic gas sensor that detects current, and further, a voltage is applied between the working electrode, the working electrode, the counter electrode, and the reference electrode separately from the working electrode, the counter electrode, or the reference electrode in the electrolyte solution storage portion. There is provided a potentiostatic gas sensor characterized by having a processing electrode used for the treatment.

  According to the present invention, the output sensitivity of the potentiostatic gas sensor can be stabilized in a shorter time without affecting the working electrode, counter electrode, and reference electrode involved in the detection of the electrode reaction during measurement. it can.

It is a schematic sectional drawing of one Example of the constant potential electrolytic gas sensor which concerns on this invention. It is a general | schematic assembly fragmentary sectional view of one Example of the constant potential electrolytic gas sensor which concerns on this invention. 1 is a schematic plan view of a sensor main body of one embodiment of a constant potential electrolytic gas sensor according to the present invention. It is a schematic diagram for demonstrating the electrode structure of one Example of the constant potential electrolytic gas sensor which concerns on this invention. It is a schematic block block diagram of the gas analyzer provided with the constant potential electrolytic gas sensor which concerns on this invention. It is a graph which shows the effect of this invention.

  Hereinafter, a stabilization method and apparatus for a constant potential electrolytic gas sensor, a method for manufacturing a constant potential electrolytic gas sensor, a gas analyzer, and a constant potential electrolytic gas sensor according to the present invention will be described in more detail with reference to the drawings.

  In general, a constant potential electrolytic cell is composed of three electrodes, a working electrode (first electrode), a counter electrode (second electrode), and a reference electrode (third electrode), and a current that flows along with an oxidation reaction or a reduction reaction at the working electrode. Measure. In actual measurement, an aging time is required until a circuit is formed in the electrolytic solution, the electrode interface potential reaches the equilibrium potential, and the electrode reaction is stabilized. Electrons necessary for stabilizing the interface potential of the working electrode are supplied through a current flowing from the counter electrode.

  For example, a working electrode such as an oxygen electrode stabilizes the surface state by using a current flowing during operation due to a reduction reaction of oxygen in the atmosphere, so that the interface potential reaches equilibrium relatively quickly, but exists in the atmosphere. A working electrode that does not react with gas is considered to require a long time for stabilization because of a small current flowing during operation.

  In the case where the electrolytic potential of the test gas is 0 mV, it is possible to make the interface potential between the working and the counter electrode uniform by providing a certain aging period before measurement by using a short plug or the like. However, it is desired to further shorten the time required for stabilizing the output. On the other hand, if the electrolytic potential of the test gas is not 0 mV and an applied voltage is required, this method cannot be applied, and it takes a very long time to stabilize the electrode surface, resulting in variations in initial sensitivity.

  Therefore, in the present invention, the current necessary for the working electrode to reach the equilibrium potential at the electrode interface is forcibly applied from the outside, the current necessary for stabilization is supplied before measurement, and the interface potential is increased more quickly. Let the equilibrium state be reached and eliminate variations in initial sensitivity. Specifically, for example, a new constant potential electrolytic gas sensor is subjected to electrolytic treatment by applying a voltage to make the working electrode surface uniform.

  At this time, if the counter electrode and reference electrode used in the measurement circuit are used, the electrode reaction may be affected. Therefore, the dedicated electrode (fourth electrode) necessary to energize the working electrode is used as the “processing electrode”. And energization between the working electrode and the fourth electrode.

  That is, it is important to keep the surface state of the counter electrode and the reference electrode used in the measurement circuit stable. When a voltage is applied between the working electrode and the working electrode in order to stabilize the interface state of the working electrode, the surface state of the working electrode or the reference electrode is forcibly changed. It is thought that it will disappear. For this reason, it may take time for the output when the electrolysis current of the test gas is detected to stabilize. Therefore, in order to stabilize the constant potential electrolytic gas sensor, it is not desirable to apply a voltage between the working electrode using the counter electrode or the reference electrode used in the measurement circuit.

  According to the present invention, a voltage is applied to the working electrode using the dedicated electrode (fourth electrode) in order to stabilize the output sensitivity of the constant potential electrolytic gas sensor. The surface state of the working electrode is stabilized while maintaining the surface state of the reference electrode and the reference electrode stably, and there is no variation in the surface of the electrode in the constant potential electrolytic gas sensor in the initial state or after long-term use, and a constant sensitivity is obtained. It becomes like this. Hereinafter, the present invention will be described in more detail with reference to more specific examples.

Example 1
[Constant potential electrolysis gas sensor]
First, an embodiment of a constant potential electrolytic gas sensor according to the present invention will be described.

  In this embodiment, the constant potential electrolytic gas sensor has a working electrode (first electrode), a counter electrode (second electrode), a reference electrode (third electrode), and the above processing electrode (fourth electrode) in a thin film shape. It is formed. In this specification, a film in which the working electrode, the reference electrode, the counter electrode, and the processing electrode are attached to the surface is collectively referred to as an “electrode carrying film”. In addition, films having the working electrode, reference electrode, counter electrode, and processing electrode attached to the surface are referred to as “working electrode carrying film”, “reference electrode carrying film”, “counter electrode carrying film”, and “processing electrode carrying film”, respectively. . Electrodes such as a working electrode, a reference electrode, a counter electrode, and a processing electrode formed in a thin film shape are collectively referred to as a “thin film electrode”.

  FIG. 1 shows a schematic cross section of a constant potential electrolytic gas sensor 100 of the present embodiment. Moreover, FIG. 2 shows the assembly partial cross section of the constant potential electrolytic gas sensor 100 of a present Example.

  The constant potential electrolytic gas sensor 100 of the present embodiment is roughly divided into an electrolytic cell unit 110 and a filter unit 120. The electrolysis cell unit 110 constitutes a constant potential electrolysis gas sensor main body for measuring the test gas, and the filter unit 120 removes interference gas for the measurement of the test gas.

  First, the electrolytic cell unit 110 will be described. The electrolytic cell unit 110 is roughly composed of a case main body 1 having a recess 13 that constitutes an electrolytic solution storage unit that stores an electrolytic solution S, and electrode supporting film groups 3A, 3B, 3C, and 3D disposed in the case main body 1. And an O-ring 5 that is an elastic member as a sealing member, and a washer 6 and a case lid 7 as pressing members that press and attach the sealing member 5 to the case body 1. Furthermore, the electrolysis cell unit 110 includes first, second, third, and fourth leads 21A, 21B, 21C, and 21D drawn from the electrodes included in the electrode supporting film groups 3A to 3D, and the first to fourth of these. First, second, third, and fourth contact pins 22A, 22B, 22C, and 22D as contact members that are connected to the leads 21A to 21D and exchange electric signals with the outside of the case body 1 are provided. Have. The first to fourth leads 21A to 21D are inserted into the case main body 1, and the first, second, third, and second passages are attached to the first to fourth contact pins 22A to 22D. Four through holes 15A, 15B, 15C, and 15D are formed.

  FIG. 3 shows the upper surface of the case body 1 of the constant potential electrolytic gas sensor 100 of the present embodiment. 1 and 2 show a cross section when the constant potential electrolytic gas sensor 100 is cut along the line AA in FIG. 3, and the first and fourth through holes 15A to 15D are shown in FIG. Four through holes 15A and 15D are shown, and the first and fourth contact pins 22A and 22D among the first to fourth contact pins 22A to 22D are shown.

  Referring to FIG. 2, case body 1 of electrolysis cell portion 110 has a lower large-diameter portion 11 and an upper small-diameter portion 12. The large diameter portion 11 has a substantially cylindrical shape, and the small diameter portion 12 has a substantially cylindrical shape concentric with the large diameter portion 11. The large-diameter portion 11 is formed with a recess 13 having an opening 13 a on the meeting surface with the small-diameter portion 12. The recess 13 is formed as a substantially cylindrical hole. The inner diameter of the concave portion 13 is smaller than the inner diameter of the hollow portion 14 of the small diameter portion 12. Therefore, a substantially annular base 19 surrounding the opening 13 a of the recess 13 is formed on the meeting surface of the large diameter portion 11 and the small diameter portion 12. In addition, a space 16 having an inner diameter smaller than the inner diameter of the recess 13 is further formed as a pressure adjusting portion at the approximate center of the bottom of the recess 13.

  As shown in FIG. 3, first to fourth through holes 15 </ b> A to 15 </ b> D are opened on the base 19 of the large diameter portion 11 along the edge of the opening 13 a of the recess 13. Each of the first to fourth through holes 15A to 15D penetrates the large diameter portion 11 of the case body 1 in the axial direction. The first to fourth contact pins 22A to 22D are attached so as to seal the end portions of the first to fourth through holes 15A to 15D on the side opposite to the base portion 19. In each of the first to fourth through holes 15A to 15D, one end of each of the first to fourth leads 21A to 21D is electrically connected to the first to fourth contact pins 22A to 22D. Connected. The arrangement of the through holes 15A to 15D around the recess 13 is not limited to that of the present embodiment.

  FIG. 4 shows the laminated structure of the electrode supporting film groups 3A to 3D on the case body 1 in more detail. In this embodiment, the counter electrode supporting film 3C, the reference electrode supporting film 3B, the processing electrode supporting film 3D, and the working electrode supporting film 3A are provided in this order from the bottom toward the opening 13a. The working electrode support film 3A, the reference electrode support film 3B, the counter electrode support film 3C, and the processing electrode support film 3D are thin film electrodes each provided with a conductive material on the porous gas permeable films 31A, 31B, 31C, and 31D. A working electrode 32A, a reference electrode 32B, a counter electrode 32C, and a processing electrode 32D are formed.

  A first water retaining sheet 4A as a first electrolyte solution holding member is disposed between the working electrode supporting film 3A and the processing electrode supporting film 3D, and the processing electrode supporting film 3D and the reference electrode supporting film 3B are arranged. A second water retention sheet 4B as a second electrolyte solution holding member is disposed between them, and a third water retention material as a third electrolyte solution holding member is interposed between the reference electrode support film 3B and the counter electrode support film 3C. A sheet 4C is disposed.

  The working electrode support film 3 </ b> A is arranged at the interface between the test gas and the electrolyte S in the case body 1 so as to cover the opening 13 a of the recess 13 serving as a storage part for the electrolyte S, thereby forming a diaphragm. The working electrode 32A is formed on the recess 13 side of the working electrode gas-permeable membrane 31A, that is, on the surface in contact with the first water retention sheet 4A. The processing electrode support film 3D is formed on the surface of the processing electrode gas-permeable film 31D on the side in contact with the first water retention sheet 4A. The reference electrode 32B is formed on the surface of the reference electrode gas-permeable membrane 31B on the side in contact with the second water retention sheet 4B. Furthermore, the counter electrode 32C is formed on the surface of the counter electrode gas-permeable membrane 31C on the side in contact with the third water retention sheet 4C.

  Here, the thin film electrode is a method in which a conductor is deposited on a polymer film by a sputtering method or a vapor deposition method, or a method in which fine particles (conductive fine particles) of a conductor are solidified with a film forming material (such as a resin). The film forming method is used. As the gas permeable films 31 </ b> A to 31 </ b> D, polymer films, in particular, fluororesin-based water-repellent (hydrophobic) films can be used. As the gas permeable membrane, other porous polymer membranes such as silicone membranes can also be used.

  In this example, a thin film made of PTFE (polytetrafluoroethylene), which is a fluororesin-based thin film, was used as the first to fourth gas permeable films 31A to 31D.

  In this embodiment, the working electrode 32A, the reference electrode 32B, the counter electrode 32C, and the processing electrode 32D are obtained by applying a mixture of a film forming material and an electrode material (conductive fine particles) to a polymer film and baking it. Formed by. That is, in this embodiment, the working electrode 32A, the reference electrode 32B, the counter electrode 32C, and the processing electrode 32D are composed of conductive fine particles and PTFE as a film forming material on a gas permeable film (PTFE film) as a polymer film. The resin powder was used to form a thin film.

  As the electrode material of the working electrode 32A, a noble metal such as platinum, palladium, gold, silver, or carbon can be used. As an electrode material of the reference electrode 32B, a noble metal such as platinum, gold or palladium, silver or silver plated with silver chloride, or carbon can be used. As an electrode material of the counter electrode 32C, a noble metal such as platinum, palladium, gold, or silver can be used. Further, platinum can be suitably used as the electrode material of the processing electrode 32D, but in addition, noble metals such as palladium, gold, silver, or carbon can be used.

As the electrolytic solution S, sulfuric acid (H ₂ SO ₄ ), phosphoric acid (H ₂ PO ₄ ) or the like is usually used, but other acid or alkaline solutions can also be used. The concentration of the electrolytic solution S is usually 1 to 10M. In this example, 5M (= mol / L) sulfuric acid (H ₂ SO ₄ ) was used.

  In this embodiment, as the first, second, and third electrolyte solution holding members 4A, 4B, and 4C, non-woven sheets made of polyester fibers were used. As the first, second, and third electrolyte solution holding members 4A, 4B, and 4C, sponges, filter papers, and the like can be used.

  One end of the first lead 21A is disposed between the working electrode 32A and the first water retaining sheet 4A. One end of the fourth lead 21D is disposed between the first water retention sheet 4A and the processing electrode 32D. One end of the second lead 21B is disposed between the second water retention sheet 4B and the reference electrode 32B. Furthermore, one end portion of the third lead 21C is disposed between the third water retention sheet 4C and the counter electrode 32C. The first to fourth leads 21 </ b> A to 21 </ b> D drawn from the interlayer are each folded back along the inner wall of the recess 13 as desired, and opened to the base 19 of the case body 1. Introduced in 15A-15D. And it reaches 1st-4th contact pins 22A-22D attached to the edge part on the opposite side to base 19 of the 1st-4th penetration holes 15A-15D. In the present embodiment, flat leads made of platinum were used as the first to fourth leads 21A to 21D. The first to fourth contact pins were made of brass plated with gold.

  Here, the working electrode 32 </ b> A, the reference electrode 32 </ b> B, the counter electrode 32 </ b> C, and the processing electrode 32 </ b> D are each formed in a substantially disk shape, and the diameter thereof is equal to or smaller than the inner diameter of the recess 13. In addition, the gas permeable membranes 31B, 31C, 31D for the reference electrode, the counter electrode, and the processing electrode, the first, second, and third water retention sheets 4A, 4B, 4C are also formed in a substantially disk shape, The diameter is equal to or smaller than the inner diameter of the recess 13. In the present embodiment, the diameters of the working electrode 32A, the reference electrode 32B, the counter electrode 32C, and the processing electrode 32D are made smaller than the diameters of the gas permeable membranes 31B, 31C, and 31D for the reference electrode, the counter electrode, and the processing electrode. In addition, the diameters of the first, second, and third water retaining sheets 4A, 4B, and 4C are substantially the same as the diameters of the gas permeable films 31B, 31C, and 31D for the reference electrode, the counter electrode, and the processing electrode. On the other hand, the gas permeable membrane 31A for the working electrode is formed in a substantially disc shape having a diameter larger than the inner diameter of the recess 13 and equal to or smaller than the inner diameter of the hollow portion 14 of the small diameter portion 12. . The members of these disk-shaped parts are arranged substantially concentrically with each other and substantially concentrically with the recess 13.

  Accordingly, the working electrode 32A, the reference electrode supporting film 3B (that is, the reference electrode gas-permeable film 31B and the reference electrode 32B), the counter electrode supporting film 3C (that is, the counter electrode gas-permeable film 31C and the counter electrode 32C), and the processing electrode support The membrane 3D (that is, the processing electrode gas-permeable membrane 31D and the processing electrode 32D), the first water retention sheet 4A, the second water retention sheet 4B, and the third water retention sheet 4C are accommodated in the recess 13. On the other hand, the working electrode gas-permeable membrane 31A is not arranged in the recess 13, and a predetermined range inside the outer edge portion of the first gas-permeable membrane 31A is arranged on the base 19 of the case body 1. The In this embodiment, the reference electrode supporting film 3B, the counter electrode supporting film 3C, and the processing electrode supporting film 3D are arranged so that the reference electrode 32B, the counter electrode 32C, and the processing electrode 32D face the upper surface, respectively. These leads 21B, 21C, and 21D may be accommodated in the recess 13 of the case body 1 in such a state that the leads 21B, 21C, and 21D are arranged directly below the respective poles.

  A washer 6 to which an O-ring 5 is attached is disposed on the case body 1 in a state where the electrode supporting film groups 3A to 3D and the first to third water retention sheets 4A to 4C are disposed on the case body 1. Then, the case lid 7 is attached to the case body 1 so as to press the washer 6 against the case body 1.

  That is, the washer 6 is a ring-shaped member having a substantially cylindrical center hole 61, and an outer edge portion on the case body 1 side is cut away to form a seal member holding portion (step portion) 62. The inner diameter of the center hole 61 of the washer 6 is equal to or larger than the inner diameter of the recess 13 of the case body 1. On the other hand, the maximum outer diameter of the washer 6 is equal to or smaller than the inner diameter of the hollow portion 14 of the small diameter portion 12 of the case body 1 and the opening portion 14a. And this washer 6 is arrange | positioned in the hollow part 14 of the small diameter part 12 of the case main body 1 from the side in which the O-ring 5 was provided.

  Thereby, the O-ring 5 is disposed in the vicinity of the outer edge portion of the working electrode carrying film 3 </ b> A disposed on the base 19. In the present embodiment, the first to fourth through holes 15 </ b> A to 15 </ b> D are opened from the edge of the recess 13 on the base 19. Accordingly, the working electrode gas-permeable membrane 31 </ b> A of the working electrode support membrane 3 </ b> A is directly sandwiched between the O-ring 5 and the base portion 19 over the entire circumference of the base portion 19. The O-ring 5 is in pressure contact with the inner wall of the hollow portion 14 of the small diameter portion 12 of the case body 1. In addition to the O-ring 5, other elastic members such as rubber packing may be used as the seal member.

  The electrolytic solution S is disposed after the counter electrode support film 3C, the reference electrode support film 3B, the processing electrode support film 3D, the first, second, and third water retention sheets 4A, 4B, and 4C are disposed in the recess 13. The working electrode support film 3 </ b> A can be accommodated in the recess 13 before being disposed on the case body 1. Alternatively, the case body 1 is separately provided with an opening for filling the electrolytic solution S into the recess 13. For example, after the recess 13 is sealed with the case lid 7 as described above, the recess 13 is opened from the opening. You may make it inject | pour the electrolyte solution S in it.

  The case lid 7 is a cap nut-like member, and a screw portion 73 that meshes with the screw portion 18 formed on the outer periphery of the small diameter portion 12 of the case main body 1 is formed on the inner peripheral surface. The case lid 7 has a center opening 71. The central opening 71 is substantially the same diameter as the central hole 61 of the washer 6 and is arranged concentrically with the central hole 61 of the washer 6 with the case lid 7 attached to the case body 1. After the washer 6 is disposed on the case main body 1, the case lid 7 is screwed into the small-diameter portion 12 of the case main body 1, whereby the washer 6 is attached to the case main body 1 by the flange portion 72 surrounding the central opening 71 of the case lid 7. Can be pressed.

  As described above, in the constant potential electrolytic gas sensor 100 of the present embodiment, the working electrode support film 3 </ b> A is formed on the base 19 surrounding the opening 13 a of the recess 13 of the case body 1 using the washer 6 and the case lid 7. It is pressed by the ring 5. In the figure, the first water retention sheet 4A, the processing electrode support film 3D, the second water retention sheet 4B, the reference electrode support film 3B, the third layer stacked below the working electrode support film 3A and disposed in the recess 13 are provided. The water retention sheet 4 </ b> C and the counter electrode support film 3 </ b> C are pressed by the working electrode support film 3 </ b> A in the recess 13. Accordingly, the recess 13 is sealed in a liquid-tight manner, and the working electrode 32A, the reference electrode 32B, the counter electrode 32C, the processing electrode 32D, and the first, second, and third electrodes disposed in the recess 13 in a stacked state. The fourth leads 21A, 21B, 21C, and 21D are in pressure contact with each other.

  Further, at least a part of each of the first to fourth through holes 15A to 15D from the opening on the base 19 to the first to fourth contact pins 22A to 22D, all in the present embodiment, Fillers 23A, 23B, 23C, and 23D can be filled so as to be sealed in a liquid-tight manner. As the fillers 23A to 23D, those having sufficient resistance to the electrolytic solution S are used. Further, it is preferable that the fillers 23A to 23D are insulating materials so as not to generate an undesired current even if they contact the first to fourth leads 21A to 21D. As the fillers 23A to 23D, a chemical-resistant resin having sufficient resistance to the sulfuric acid used as the electrolytic solution S, for example, an adhesive can be suitably used. For example, an epoxy resin adhesive can be used as the fillers 23A to 23D.

  Next, the filter unit 120 will be described. In the present embodiment, the filter unit 120 includes a filter attachment 8 and an interference gas removal filter 9. The interference gas removal filter 9 is detachably attached to the case body 1 by attaching the interference gas removal filter 9 to the filter attachment 8 attached to the case body 1.

  The fixture 8 is a cylindrical member having a hollow portion 81, and is formed on the outer peripheral surface of the large-diameter portion 11 of the case body 1 on the inner peripheral surface of one end portion in the axial direction (the lower side in the figure). A screw portion 82 that meshes with the screw portion 17 is formed. The attachment 8 is placed from the case lid 7 side of the case body 1 after the case lid 7 is attached, and is screwed into the large diameter portion 11.

An interference gas removal filter 9 is attached to the other end (upper side in the figure) of the attachment 8 in the axial direction. The interference gas removal filter 9 has a filter main body 91 and a filter seal member 92 attached to the outer periphery of the filter main body 91. The interference gas removal filter 9 is firmly attached to the fixture 8 by press-fitting the filter seal portion 92 to the inner peripheral surface of the end of the fixture 8. The filter main body 91 has air permeability and allows the atmospheric gas of the constant potential electrolytic gas sensor 100 to pass toward the electrolytic cell unit 110, and the gas from the electrolytic cell unit 110 to the outside of the constant potential electrolytic gas sensor 100. Although it is allowed to pass through, an absorbent that absorbs interference gas that affects measurement in the electrolytic cell unit 110 is provided in the ventilation path. For example, when the constant potential electrolytic gas sensor 100 is configured as a NO or NO ₂ sensor, the filter main body 91 absorbs NO ₂ and SO ₂ that are interference gases and absorbs and removes NO and SO ₂ . And an absorbent to be removed.

  In the present embodiment, the case main body 1, the washer 6, the case lid 7, and the fixture 8 are molded from plastic.

In this embodiment, the constant potential electrolysis gas sensor 100 has a working electrode (first electrode) 32A, a counter electrode (second electrode) 32C, and a reference electrode (third electrode) 32B as electrodes involved in measurement of the test gas. In addition to this, a processing electrode (fourth pole) 32D is further provided. However, the present invention is not limited to this, and has a working electrode (first electrode) 32 </ b> A and a counter electrode (second electrode) 32 </ b> C as electrodes related to measurement of the test gas (that is, a reference electrode (third electrode)). (Pole) 32B is not included), and in addition to this, a processing electrode (fourth electrode) may be included. For example, in the case of a CO sensor, an O ₂ sensor, or the like in which the measurement target gas is CO or O ₂ , a configuration without the reference electrode (third electrode) 32B may be adopted.

[Gas analyzer]
Next, with reference to FIG. 5, an embodiment of a gas analyzer equipped with the constant potential electrolytic gas sensor 100 according to the present invention will be described.

  The gas analyzer 200 obtains the concentration of the test gas from the electrolysis current when the test gas is electrolyzed at a constant potential. As shown in FIG. 5, the gas analyzer 200 includes a constant potential electrolytic gas sensor 100 and a calculation display unit 300. Typically, the constant potential electrolytic gas sensor 100 is detachable from the calculation display unit 300. The calculation display unit 300 monitors and adjusts the potential between the working electrode 32A and the reference electrode 32B so as to keep the interface between the working electrode 32A and the electrolyte S of the constant potential electrolytic gas sensor 200 at a constant potential. Yes. At that time, the electrolytic current flowing between the working electrode 32A and the counter electrode 32C is amplified and calculated to display the concentration of the test gas. This electrolytic current is obtained by a reaction in which the test gas diffused and absorbed in the electrolyte S through the working electrode gas-permeable diaphragm 31A is oxidized or reduced at the working electrode 32A. The constant potential electrolytic gas sensor 100 is configured such that the electrolysis current value is proportional to the concentration of the test gas, and the calculation display unit 300 measures the electrolysis current value to convert it into the test gas concentration.

  A measurement signal from the constant potential electrolytic gas sensor 100 is transmitted to the calculation display unit 300, and the calculation display unit 300 calculates and displays the concentration of the test gas. In the present embodiment, the calculation display unit 300 includes a converter 301 as measurement means to which the working electrode 32A, the reference electrode 32B, and the counter electrode 32C are connected. The converter 301 includes a constant potential circuit 302 that includes a variable voltage power source and applies a constant potential to the working electrode 32A, and an arithmetic control unit (CPU) 303 that calculates a test gas concentration from the measured electrolytic current value. It has.

  In addition, the arithmetic control unit (CPU) 303 of the converter 301 is configured to execute a stabilization process that embodies the stabilization method according to the present invention. In this embodiment, the processing electrode 32D is also connected to the constant potential circuit 302, and the constant potential circuit 302 applies a voltage to apply a voltage between the working electrode 32A and the processing electrode 32D in the stabilization process. Functions as a means.

  Further, the converter 301 has a storage means (electronic memory) 304 in which an operation program of the gas analyzer 200 such as a measurement procedure and a stabilization processing procedure is stored.

  Further, in the present embodiment, the calculation display unit 300 includes a display unit 305 that displays the calculated gas concentration to be detected, an input unit 306 for inputting various settings, and the like.

  The stabilization process will be described in detail later.

  The electrode material, the type of the electrolyte S, the applied voltage (potential difference between the working electrode 5 and the reference electrode 6, the set electrolysis potential), and the like are selected depending on the type of measurement target gas. Normally, the set electrolysis potential minimizes the influence of the interference gas on the test gas and is limited to the limit current (the current value does not change due to potential fluctuation and is proportional to the test gas concentration). To change).

In this embodiment, as an example, to a constant potential electrolysis type gas sensor 100, NO sensors, the case of using the NO ₂ sensor. Table 1 shows the set electrolytic potential (applied voltage), working electrode, counter electrode, reference electrode, and processing electrode material in an example of a NO sensor and a NO ₂ sensor.

The NO sensor measures an oxidation current due to oxidation of NO to nitric acid (HNO ₃ ) at the working electrode 32A at a set electrolytic potential of +300 mV. The NO ₂ sensor measures the reduction current due to the reduction reaction of NO ₂ to NO at the working electrode 32A at the set electrolysis potential of 0 mV.

The present invention can be applied to, for example, an SO ₂ sensor and a CO sensor in addition to the NO sensor and the NO ₂ sensor. In this case, as an example, the SO ₂ sensor measures an oxidation current due to oxidation of SO ₂ to H ₂ SO ₄ at the working electrode at a set electrolysis potential of 0 mV. Further, as an example, the CO sensor in the setting electrolysis potential 0 mV, measuring the oxidation current due to the oxidation reaction of carbon dioxide to CO at the working electrode (CO _2).

[Stabilization method]
As described above, in the initial state when the user uses the potentiostatic gas sensor 100 for the first time, there are variations in output, and long-term aging is required until a certain output sensitivity is obtained.

  In addition, when the constant potential electrolysis gas sensor 100 is left for a certain period of time, for example, when it is stored in a dry state, the sensitivity is deteriorated, and then a stable output can be obtained again for a long time. Aging may be required.

  In addition, when the potentiostatic gas sensor 100 is used for a long time, the output may gradually decrease, and then long-term aging is required to obtain a stable output again. There is a case.

  Therefore, typically, before using the potentiostatic gas sensor 100 for the first time, or after using the potentiostatic gas sensor 100 for a certain period of time, and before using it for the first time, The stabilization process according to the present invention can be applied to the potentiostatic gas sensor 100. In addition, the stabilization treatment according to the present invention may be performed on the constant potential electrolytic gas sensor 100 before the use is started again after the sensitivity is deteriorated by using the constant potential electrolytic gas sensor 100 for a certain period of time. it can.

  The stabilization treatment according to the present invention has two electrodes, the working electrode 32A and the counter electrode 32C, or the working electrode 32A, the counter electrode 32C, and the reference electrode 32D in the electrolyte solution storage unit 13 that stores the electrolyte S. A method for stabilizing the constant potential electrolytic gas sensor 100 that detects the electrolysis current of the test gas at the working electrode 32A is implemented. What is the working electrode 32A, the counter electrode 32C, or the reference electrode 32B in the electrolyte container 13? A process of applying a voltage between the processing electrode 32D and the working electrode 32A provided separately is performed. This stabilization process is performed in a state in which the constant potential electrolytic gas sensor 100 is assembled and the electrolytic solution S is stored in the electrolytic solution storage unit 13.

  Although not intended to be bound by any theory, when a voltage is applied between the working electrode and another electrode, the surface of the working electrode is physically removed by the electrolytic cleaning. It seems that the time until the sensitivity output is stabilized is drastically reduced. At this time, in order to stabilize the interface state of the working electrode, when a voltage is applied between the working electrode using the counter electrode or the reference electrode, the surface state of the counter electrode or the reference electrode is forcibly changed, The natural state is lost, and therefore it may take time for the output to stabilize during measurement. Therefore, in order to stabilize the constant potential electrolytic gas sensor, it is not desirable to apply a voltage between the working electrode using the counter electrode or the reference electrode used in the measurement circuit.

  In contrast, in the stabilization process according to the present invention, in order to stabilize the output sensitivity of the constant potential electrolytic gas sensor 100, a voltage is applied to the working electrode 32A using the processing electrode 32D that is a dedicated electrode. Therefore, by this stabilization treatment, the surface state of the working electrode 32A is stabilized while maintaining the surface state of the counter electrode 32C and the reference electrode 32D stably, and the electrolytic cell (electrolyte container) ) There is no variation in the pole surface in 13 and a certain sensitivity can be obtained.

  The potential of the voltage applied between the working electrode 32A and the processing electrode 32D in the stabilization processing is typically different from the potential of the working electrode 32A when detecting the electrolytic current of the test gas. The voltage applied in the stabilization process can be appropriately set so as to obtain a desired stabilization time shortening effect. According to the study of the present inventor, the potential of the voltage applied between the working electrode 32A and the processing electrode 32D in the stabilization process is equal to the potential of the working electrode 32A when detecting the electrolytic current of the test gas. The potential may be on the positive side or on the negative side, and typically has a difference of 500 mV or more and 2 V or less with respect to the potential of the working electrode 32A when detecting the electrolysis current of the test gas. It is preferable. That is, the absolute value of the difference between the potential of the working electrode 32A during measurement and the potential of the voltage applied between the working electrode 32A and the processing electrode 32D during the stabilization process is preferably 500 mV to 2 V (that is, If the potential of the working electrode 32A during measurement is 0 mV, the potential of the voltage applied between the working electrode 32A and the processing electrode 32D during the stabilization process is preferably +500 mV to +2 V, or −500 mV to −2 V. ). The voltage applied in the stabilization process may be a direct current (DC) voltage or an alternating current (AC) voltage. In the case of an alternating voltage, it is preferable to apply a voltage that provides a difference in the above range on at least one of the polar sides with respect to the potential of the working electrode 32A when detecting the electrolytic current of the test gas.

  If the voltage applied in the stabilization process is smaller than the above range, the effect of shortening the stabilization time may not be significant. On the other hand, even if the above range is exceeded, the effect of shortening the time required for stabilization is not so much promoted, and instead electrolysis of water, generation of hydrogen, etc. may occur, which may be a problem.

  As described above, typically, the stabilization process is left before using the potentiostatic gas sensor 100 for the first time or without being used for a certain period of time since the use of the potentiostatic gas sensor 100 has been started. Can be done later before first use. The voltage application time in this stabilization process can be appropriately selected according to the desired degree of stabilization. According to the study by the present inventor, the voltage application time in the stabilization process is preferably 1 to 30 minutes. The voltage application in the stabilization process can be performed in a pulse manner at a predetermined time interval. For example, the stabilization process can be performed by applying a voltage between the working electrode 32A and the processing electrode 32B every 0.1 to 10 minutes for 0.1 second to 10 minutes.

  Further, as described above, the stabilization process can be performed before the use is started again after the sensitivity is deteriorated by using the constant potential electrolytic gas sensor 100 for a certain period of time. That is, by using the constant potential electrolysis gas sensor 100, the sensitivity that deteriorates to various degrees by each sensor can be recovered by the stabilization processing according to the present invention, so that a constant sensitivity can be obtained. . In this case, stabilization processing, that is, processing for applying a voltage between the working electrode 32A and the processing electrode 32D can be performed periodically. That is, a voltage is applied between the working electrode 32A and the processing electrode 32D for a predetermined time at a predetermined timing such as every time a constant time elapses by using the constant potential electrolytic gas sensor 100. At this time, the stabilization process is performed in a pulsed manner, that is, the voltage applied between the working electrode 32A and the processing electrode 32D in the stabilization process is applied in a pulsed manner at a predetermined time interval, so that the measurement can be performed for a long time. Sensitivity reduction can be recovered without interruption. For example, for the potentiostatic gas sensor 100 in the measurement state, 0.1 second to 10 minutes every 1 minute to 1 day, usually 0.1 second to 1 minute every 1 minute to 1 hour, preferably 0. The stabilization process can be performed by applying a voltage between the working electrode 32A and the processing electrode 32B for an extremely short time such as 1 second to 10 seconds. Alternatively, a stabilization process may be performed by applying a voltage between the working electrode 32A and the processing electrode 32D every 1 hour to 30 days, usually every 10 hours to 5 days, for 1 minute to 30 minutes. However, the interval for performing the stabilization process and the time for applying the voltage in the stabilization process can be appropriately selected so as to obtain a desired sensitivity recovery effect.

  The stabilization process may be performed in a state where the constant potential electrolytic gas sensor 100 is in the measurement system, that is, in the test gas, or may be performed in the air that does not substantially include the test gas. For example, the stabilization process before starting the use of the potentiostatic gas sensor 100 or leaving it for a certain period and before using it again can be performed in air containing no test gas. Further, for example, when the stabilization process is performed periodically (preferably in a pulse manner) for the constant potential electrolytic gas sensor 100 in use, the constant potential electrolytic gas sensor 100 is stable in a state where it is in the measurement system. Processing can be performed.

  The stabilization process is performed by a circuit for stabilizing the constant potential electrolytic gas sensor 100 incorporated in the electric circuit unit of the calculation display unit 300. In the present embodiment, the constant potential circuit 302 included in the converter 301 of the calculation display unit 300 functions as a voltage applying unit that applies a voltage between the working electrode 32A and the processing electrode 32D in the stabilization process. The operator can execute the stabilization process at an arbitrary timing from the input unit 306 provided in the calculation display unit 300. Alternatively, the calculation control unit (CPU) 303 of the converter 301 may automatically execute the stabilization process according to a computer program stored in the storage unit (electronic memory) 304 of the converter 301.

[Stabilizer]
As described above, the stabilization process according to the present invention can be executed in the gas analyzer 200 including the constant potential electrolytic gas sensor 100 according to the present invention. As described above, the stabilization device (stabilization unit) of the potentiostatic gas sensor 100 may be incorporated in the gas analyzer 200.

  That is, in the present embodiment, the electrolytic solution storage unit 13 that stores the electrolytic solution S has two working electrodes 32A and a counter electrode 32C, or three working electrodes 32A, a counter electrode 32C, and a reference electrode 32B. A stabilization device (stabilization unit) of the constant potential electrolytic gas sensor 100 that detects the electrolysis current of the test gas at the pole 32A is incorporated in the gas analyzer 200. This stabilization device (stabilization unit) applies a voltage between the processing electrode 32D and the working electrode 32A, which are provided in the electrolyte solution storage unit 13 separately from the working electrode 32A, the counter electrode 32C, or the reference electrode 32D. It has a voltage application means and performs the stabilization process according to this invention. In this embodiment, the function of the voltage applying means is provided in the constant potential circuit 302 of the converter 301 provided in the calculation display unit 300. And the stabilization process by this stabilization apparatus (stabilization unit) is performed by the circuit for the stabilization process of the constant potential electrolytic gas sensor 100 incorporated in the electric circuit part of the calculation display part 300. As described above, the stabilization process by the stabilization device (stabilization unit) is performed by an operator instructing from the input unit 306 provided in the calculation display unit 300 or by the calculation control unit (CPU) 303 of the converter 301. Automatically executed by control by

  However, the present invention is not limited to this, and the stabilization device incorporated in the gas analyzer 200 is configured as a special device mainly for the purpose of performing the stabilization process. Also good. For example, as will be described later, this stabilization device can be used when a stabilization process is performed in the manufacturing process of the potentiostatic gas sensor 100.

[Manufacturing Method of Constant Potential Electrolytic Gas Sensor]
According to the present invention, by introducing the stabilization process according to the present invention into the manufacturing process of the controlled potential electrolytic gas sensor 100, it is possible to provide the controlled potential electrolytic gas sensor 100 whose output sensitivity has been stabilized.

  That is, in the method for manufacturing the constant potential electrolytic gas sensor 100 according to the present invention, the working electrode 32A, the counter electrode 32C, or the working electrode 32A, the counter electrode 32C, and the reference electrode are provided in the electrolyte solution storage unit 13 that stores the electrolyte solution S. In manufacturing the constant potential electrolytic gas sensor 100 having the three electrodes 32D and detecting the electrolysis current of the test gas in the working electrode 32A, at least (i) the working electrode 32A and the counter electrode 32C are provided in the electrolyte container 13. Or the process electrode 32D is provided separately from the reference electrode 32D, and (ii) the process of applying a voltage between the process electrode 32D and the working electrode 32A is included.

  The assembly process of the potentiostatic gas sensor 100 including the step (i) of providing the processing electrode 32D is as described above. Further, the process (ii) may be the same as the stabilization process described as being performed before the use of the constant potential electrolytic gas sensor 100. The stabilization process step (ii) is performed in a state in which the constant potential electrolytic gas sensor 100 is assembled and the electrolytic solution S is stored in the electrolytic solution storage unit 13.

  Thereby, the output sensitivity of the potentiostatic gas sensor 100 can be stabilized in a shorter time and without affecting the counter electrode and the reference electrode when the potentiostatic gas sensor 100 is manufactured. Therefore, variation in output sensitivity before the measurement of the constant potential electrolytic gas sensor 100 can be suppressed, and constant output sensitivity can be obtained.

  And since the user does not need to stabilize the output sensitivity before using the provided potentiostatic gas sensor 100 or the time required for the stabilization process is shorter, for example, After the constant potential electrolytic gas sensor 100 is replaced, the measurement can be started or restarted quickly.

Test example 1
Next, test examples for confirming the effects of the present invention will be described.

Using the new NO sensor and NO ₂ sensor according to Example 1, the output sensitivity to the test gas (component NO, NO ₂ ) was measured when the stabilization process according to the present invention was performed and when it was not performed.

In the stabilization process, a voltage of 1.5 V between the working electrode 32A and the processing electrode 32D (that is, 1.2 V for the NO sensor with respect to the potential of the working electrode 32 when measuring the electrolytic current of the test gas). In the NO ₂ sensor, a voltage having a difference of 1.5 V) was applied for 10 minutes. The results are shown in FIG.

  From FIG. 6, by performing the stabilization process according to the present invention, the sensitivity (output current value of 20 μA or more) similar to that when aging for a long time (150 days) is obtained in the stabilization process for a short time (10 minutes). It was. This is presumably because the surface of the working electrode 32A was electrolytically cleaned by the stabilization treatment, and the state of the interface potential became uniform.

  Further, among the plurality of sensors used in the test, the output sensitivity varied before the stabilization process, but the output sensitivity (output current value) became almost constant at 20 μA or more after the stabilization process. Thus, it is considered that the stabilization state of each sensor has almost reached saturation even in a short time in this test.

32A Working electrode 32B Reference electrode 32C Counter electrode 32D Processing electrode 100 Constant potential electrolytic gas sensor 200 Gas analyzer 300 Calculation display unit

Claims (13)

Constant-potential electrolysis type that has two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode in the electrolyte container that contains the electrolyte, and detects the electrolysis current of the test gas at the working electrode A method for stabilizing a gas sensor,
Stabilization of a potentiostatic gas sensor characterized by performing a process of applying a voltage between a working electrode provided separately from the working electrode, counter electrode or reference electrode in the electrolyte container and the working electrode Method.   2. The method for stabilizing a constant potential electrolytic gas sensor according to claim 1, wherein the potential of the voltage in the processing is different from the potential of the working electrode when detecting the electrolytic current of the test gas.   The method for stabilizing a constant potential electrolytic gas sensor according to claim 1 or 2, wherein the voltage in the processing is applied in a pulse manner at a predetermined time interval.   The method for stabilizing a constant potential electrolytic gas sensor according to any one of claims 1 to 3, wherein the voltage in the treatment is applied for 1 to 30 minutes.   The potential of the voltage in the treatment has a difference of 500 mV or more and 2 V or less with respect to the potential of the working electrode when detecting the electrolysis current of the test gas. A method for stabilizing a constant potential electrolysis gas sensor as described in the section. Constant-potential electrolysis type that has two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode in the electrolyte container that contains the electrolyte, and detects the electrolysis current of the test gas at the working electrode A method for manufacturing a gas sensor, comprising:
Providing a treatment electrode separately from the working electrode, counter electrode or reference electrode in the electrolyte container;
Performing a process of applying a voltage between the processing electrode and the working electrode;
A method for producing a constant potential electrolytic gas sensor, comprising:   The method of manufacturing a constant potential electrolytic gas sensor according to claim 6, wherein the potential of the voltage in the processing is different from the potential of the working electrode when detecting the electrolytic current of the test gas.   The method of manufacturing a constant potential electrolytic gas sensor according to claim 6 or 7, wherein the voltage in the treatment is applied in a pulse manner at a predetermined time interval.   The method for producing a constant potential electrolytic gas sensor according to any one of claims 6 to 8, wherein the voltage in the treatment is applied for 1 to 30 minutes.   The potential of the voltage in the treatment has a difference of 500 mV or more and 2 V or less with respect to the potential of the working electrode when detecting the electrolytic current of the test gas. A manufacturing method of a constant potential electrolytic gas sensor described in 1. Constant-potential electrolysis type that has two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode in the electrolyte container that contains the electrolyte, and detects the electrolysis current of the test gas at the working electrode A gas sensor stabilization device comprising:
6. The apparatus according to claim 1, further comprising a voltage applying unit configured to apply a voltage between the working electrode and the working electrode provided separately from the working electrode, the counter electrode, or the reference electrode in the electrolytic solution storage unit. A stabilizing device for a constant potential electrolytic gas sensor, characterized by performing the treatment described in the section. Constant-potential electrolysis type that has two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode in the electrolyte container that contains the electrolyte, and detects the electrolysis current of the test gas at the working electrode A gas analyzer equipped with a gas sensor,
The constant potential electrolytic gas sensor has a processing electrode separately from the working electrode, the counter electrode, or the reference electrode in the electrolyte container, and further, in the working electrode detected by the constant potential electrolytic gas sensor. 6. The measuring device according to claim 1, further comprising: a measuring unit that measures an electrolytic current of the test gas; and a voltage applying unit that applies a voltage between the processing electrode and the working electrode. A gas analyzer characterized in that processing can be performed.   Constant-potential electrolysis type that has two working electrodes and a counter electrode, or three working electrodes, a counter electrode, and a reference electrode in the electrolyte container that contains the electrolyte, and detects the electrolysis current of the test gas at the working electrode A gas sensor, further comprising a processing electrode used for applying a voltage between the working electrode, the counter electrode, or the reference electrode in the electrolytic solution storage unit, separately from the working electrode, for the stabilization process. A constant potential electrolytic gas sensor comprising: