WO2022259883A1 - Hydrogen gas concentration sensor - Google Patents
Hydrogen gas concentration sensor Download PDFInfo
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- WO2022259883A1 WO2022259883A1 PCT/JP2022/021641 JP2022021641W WO2022259883A1 WO 2022259883 A1 WO2022259883 A1 WO 2022259883A1 JP 2022021641 W JP2022021641 W JP 2022021641W WO 2022259883 A1 WO2022259883 A1 WO 2022259883A1
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- electrode
- hydrogen gas
- electrode piece
- gas concentration
- concentration sensor
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- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims description 118
- 239000003792 electrolyte Substances 0.000 claims abstract description 29
- 239000007772 electrode material Substances 0.000 claims abstract description 17
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- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 17
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 16
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 6
- 229910052763 palladium Inorganic materials 0.000 claims description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 4
- 229910052802 copper Inorganic materials 0.000 claims description 4
- 239000010949 copper Substances 0.000 claims description 4
- 229910052697 platinum Inorganic materials 0.000 claims description 4
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 4
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- 229910000990 Ni alloy Inorganic materials 0.000 claims description 3
- 229910001252 Pd alloy Inorganic materials 0.000 claims description 3
- 229910001260 Pt alloy Inorganic materials 0.000 claims description 3
- 229910001069 Ti alloy Inorganic materials 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
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- IYDGMDWEHDFVQI-UHFFFAOYSA-N phosphoric acid;trioxotungsten Chemical compound O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.OP(O)(O)=O IYDGMDWEHDFVQI-UHFFFAOYSA-N 0.000 description 1
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Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/403—Cells and electrode assemblies
- G01N27/406—Cells and probes with solid electrolytes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/416—Systems
Definitions
- the present invention relates to a hydrogen gas concentration sensor.
- hydrogen concentration sensors for controlling hydrogen fuel cells in automobiles and heavy machinery efficiency use of hydrogen gas
- hydrogen concentration sensors for liquids such as lubricating oil for generator bearings and transformer oil
- hydrogen concentration sensor in medical chemicals such as kidney dialysis (promotes treatment effect by dissolving hydrogen)
- hydrogen concentration sensor in solution such as hydrogen water, process control in chemical industry, etc.
- the development of a hydrogen concentration sensor for gas is desired.
- a hydrogen gas concentration sensor for shortening the detection time includes, for example, a first electrode and a second electrode made of materials having different chemical potentials with respect to hydrogen, and an electrolyte in contact with these electrodes.
- a hydrogen gas sensor has been proposed that detects hydrogen gas based on the value of the electromotive force generated in (Patent Document 1).
- the first electrode, the second electrode and the electrolyte are covered with an outer skin.
- the first electrode, which is the sensing electrode be exposed from the skin and immersed in the liquid, while the electrolyte must be sealed from the liquid. Therefore, the structure of the hydrogen gas sensor becomes complicated, and the sealing method poses technical and economic problems.
- An object of the present invention is to provide a hydrogen gas concentration sensor of a novel configuration capable of detecting the concentration of hydrogen gas present in environments such as special gases and liquids used in the chemical industry under high-temperature and high-humidity environments. aim.
- the present invention is as described below.
- the first electrode piece is a first electrode material exhibiting a standard electromotive force value of 0.8 V or more in a cell composed of H 2 ( ⁇ )
- a hydrogen gas concentration sensor with a novel configuration that is capable of detecting the concentration of hydrogen gas in special gases and liquids used in the chemical industry under high-temperature and high-humidity environments.
- FIG. 4 is a graph showing the EMF value when a platinum wire is used as the first electrode piece of the hydrogen gas concentration sensor in the example.
- 4 is a graph showing EMF values when a palladium wire is used as the first electrode piece of the hydrogen gas concentration sensor in the example.
- 4 is a graph showing the hydrogen gas concentration and the EMF value when a platinum wire is used as the first electrode piece of the hydrogen gas concentration sensor in the example.
- 4 is a graph showing the relationship between the hydrogen gas concentration and the EMF value when a palladium wire is used as the first electrode piece of the hydrogen gas concentration sensor in the example.
- FIG. 1 is a schematic configuration diagram of a hydrogen gas concentration sensor according to this embodiment.
- the hydrogen gas concentration sensor 10 of this embodiment includes a first linear electrode piece 11, a second linear electrode piece 12, and an electrolyte 14 in which these electrode pieces are spaced apart. , and a container 15 with one end sealed to accommodate the first electrode piece 11 , the second electrode piece 12 and the electrolyte 14 .
- the container 15 is arranged such that its tip is inserted into the system to be measured. Therefore, the inside of the container 15 is gas-insulated from the system to be measured.
- the first electrode piece 11 functions as a hydrogen gas detection electrode, its tip penetrates through the sealed portion of the electrolyte 14 and is exposed to the outside of the container 15 .
- the portion of the first electrode piece 11 that penetrates the container 15 is melt-sealed.
- the second electrode piece 12 is made of a material with a relatively low chemical potential and does not affect the detection of hydrogen gas. Like the electrode piece 11 , it can be exposed to the outside from the sealed portion of the container 15 . However, in general, it is preferable not to expose the sensor 15 to the outside of the container 15 , because re-melting and sealing is generally required, which complicates the structure and manufacturing process of the hydrogen gas concentration sensor 10 .
- the linear temperature compensating third electrode piece 13 is arranged to eliminate the influence of the environmental temperature. It is The third electrode piece 13 is also arranged with respect to the electrolyte 14 so as to be separated from the first electrode piece 11 and the second electrode piece 12 .
- first electrode piece 11, the second electrode piece 12 and the third electrode piece 13 are connected to the rear end opening of the container 15 on the side opposite to the sealed portion of the container 15 in order to measure the electromotive force associated with the detection of the hydrogen gas concentration. It is arranged so as to extend outward from the container 15 from the part.
- the first electrode piece 11 functions as a detection electrode for hydrogen gas, and when it comes into contact with hydrogen gas, the chemical potential of (atomic) hydrogen changes greatly.
- the second electrode piece 12 functions as a reference electrode for hydrogen gas, and when it comes into contact with hydrogen gas, its chemical potential hardly changes or changes very little.
- the first electrode piece 11 can be made of a first electrode material with a relatively high chemical potential, specifically H 2 ( ⁇ )
- the above materials include materials with relatively high adsorption activity for hydrogen gas, such as platinum and platinum alloys.
- the first electrode piece 11 can be composed of these materials themselves, these materials can be used by carrying them on a predetermined substrate. However, it can be used in any manner as long as it functions as a detection electrode for hydrogen gas without departing from the scope of the present invention.
- the material described above it is also possible to use a material with relatively high adsorption activity for hydrogen gas, such as palladium or a palladium alloy.
- the first electrode piece 11 can be made of these materials themselves, but these materials can also be used by carrying them on a predetermined substrate. However, it can be used in any manner as long as it functions as a detection electrode for hydrogen gas without departing from the scope of the present invention.
- the hydrogen molecules are dissociated, so that the hydrogen gas adsorbed on the first electrode piece 11 is quickly detached. It is suitable as a detection electrode for a hydrogen gas concentration sensor that responds quickly, such as a hydrogen gas concentration sensor dissolved in water.
- the first electrode piece 11 when the first electrode piece 11 is made of a palladium-based material, the amount of hydrogen corresponding to the hydrogen partial pressure dissolves in solid solution, but the dissolved hydrogen is difficult to escape. It takes time. Therefore, when the first electrode piece 11 is made of a palladium-based material, the first electrode piece 11 has a memory function and can be applied as a detection electrode suitable for checking deterioration of transformer oil, for example.
- the second electrode piece 12 can be made of a material with a relatively low chemical potential, specifically H 2 ( ⁇ )
- the second electrode material exhibits a cell standard electromotive force value of less than 0.8V.
- the materials mentioned above include tungsten, tungsten alloys, nickel, nickel alloys, titanium, titanium alloys, copper, copper alloys, iron, iron alloys, aluminum, aluminum alloys and organic conductive materials, which have relatively high adsorption activity for hydrogen gas. Low degree materials can be mentioned. However, it can be used in any manner as long as it functions as a reference electrode for hydrogen gas without departing from the scope of the present invention.
- the third electrode piece 13 is an electrode piece for temperature compensation, and is arranged to offset changes in the environmental temperature of the hydrogen gas concentration sensor 10, that is, the environmental temperature of the first electrode piece 11, which is the detection electrode. Therefore, it is preferable to use the same material as the first electrode piece 11 .
- the electrolyte 14 can be composed of an electrolyte having excellent adhesion to the first electrode 21 and the second electrode 22, such as phosphotungstic acid. Electrolyte 14 may include structural reinforcements such as glass wool in addition to electrolyte materials such as phosphotungsten. In this case, the strength of the electrolyte 14 can be increased, and the adhesion between the first electrode piece 11 and the second electrode piece 12 can be further increased.
- the container 15 is preferably made of glass, resin, ceramics, or the like in order to ensure insulation between the first electrode piece 11 and the second electrode piece 12 .
- the container 15 is made of an electrically conductive material such as metal, it is preferable to insulate the first electrode piece 11 from the container 15 by coating it with resin or ceramic.
- a first electrode material having a value of 0.8 V or more is included, and the second electrode piece 12 includes a second electrode material having a standard electromotive force value of less than 0.8 V in a cell with the same configuration.
- the first electrode piece 11 penetrates the electrolyte 14 and has an end exposed outside from the container 15 .
- the first electrode piece 11 exposed from the container 15 of the hydrogen gas concentration sensor 10 should be immersed in a liquid containing dissolved hydrogen gas. At this time, even if the tip portion of the container 15 is immersed in the liquid, the electrolyte 14 itself is housed and sealed in the container 15 and is therefore not immersed in the liquid. That is, the hydrogen gas concentration sensor 10 can detect the concentration of hydrogen gas dissolved in the liquid by means of the first electrode piece 11, which is the detection electrode, and the second electrode piece 12, which is the reference electrode, both of which are immersed in the liquid. can. Similarly, it is possible to detect the concentration of hydrogen gas in special gases such as those used in high-temperature, high-humidity environments or in the chemical industry.
- the hydrogen gas concentration sensor 10 of this embodiment it is sufficient to immerse the tip portion in the liquid and immerse the first electrode piece 11 as the detection electrode in the liquid. Therefore, unlike the conventional sealed hydrogen gas concentration sensor, it is not necessary to expose at least the first electrode, which is the detection electrode, from the outer skin and immerse it in the liquid, and to seal the electrolyte from the liquid with the outer skin. That is, the hydrogen gas concentration can be detected with an extremely simple configuration.
- the hydrogen concentration of the hydrogen gas concentration sensor 10 of this embodiment is detected by the electromotive force generated between the first electrode piece 11 and the second electrode piece 12.
- the electromotive force is expressed by the following relational expression. generated based on
- E is the EMF value
- F Faraday constant
- E the EMF value
- ⁇ I the electrostatic potential of the first electrode
- ⁇ II the electrostatic potential of the second electrode.
- the temperature compensation by the third electrode piece 13 is ( ⁇ : adsorption energy, k: Boltzmann constant, T: temperature, n: hydrogen concentration) and can be done by subtracting this E value from the EMF value above.
- the hydrogen concentration exceeds 1% (n is 0.01 or more)
- the E value becomes a very small value, so temperature compensation does not need to be considered, and the third electrode piece 13 itself can also be omitted.
- a hydrogen gas concentration sensor 10 shown in FIG. 1 was prepared, and a simple hydrogen gas detection test was carried out.
- a platinum wire and a palladium wire with a diameter of 0.2 mm were used for the first electrode piece 11, and a tungsten wire with a diameter of 0.2 mm was used for the second electrode piece 12.
- the third electrode piece 13 is omitted for simplification.
- the first electrode piece 11 and the second electrode piece 12 are arranged on the electrolyte 14 made of cesium phosphotungstate with a gap of 0.2 mm.
- 14 was housed in a glass tube 15 having a diameter of 6 mm and a length of 25 mm, and the first electrode piece 11 was exposed with a length of 3 mm from the tip of the glass tube 15 and melt-sealed. Note that the exposed portion may be cut off at the root portion.
- the electrolyte and electrodes There are also no special restrictions on the arrangement of the electrolyte and electrodes.
- the first electrode piece 11 and the second electrode piece 12 were exposed from the rear end side of the glass tube 15 so that the electromotive force could be measured by detecting the hydrogen gas concentration.
- FIG. 2 shows the detected voltage (V) when a platinum wire is used as the first electrode piece 11
- FIG. 3 shows the detected voltage (V) when a palladium wire is used as the first electrode piece 11.
- the hydrogen gas concentration was adjusted by filling hydrogen gas into a sealed container having an opening for inserting the glass container 15, and the detected electromotive force was measured at the rear end opening of the glass tube 15. Measured at
- the detection voltage decreases from 0.4 V to 0.03 V by detecting hydrogen gas. It can be seen that the electromotive force immediately recovers to 0.4 V when the voltage is cut off. That is, it can be seen that hydrogen gas desorbs quickly and is suitable as a detection electrode for a hydrogen gas concentration sensor with fast response. Assuming a fuel cell control sensor, the measurement result was obtained at a temperature of 85°C.
- the hydrogen concentration was set to 10% to compare the responsiveness to hydrogen gas.
- the value of the spontaneous electromotive force of the sensor which is a feature of the EMF type hydrogen sensor, was measured at the rear end opening of the glass tube 15 with an electrometer.
- the hydrogen gas concentration sensor 10 configured as shown in FIG. 1 can detect the hydrogen gas concentration and functions as a sensor. Therefore, it can be seen that the hydrogen gas concentration sensor 10 shown in FIG. 1 can be applied to liquids such as oil to detect the concentration of hydrogen gas dissolved in these liquids.
- the detection voltage increases as the hydrogen gas concentration increases while maintaining its memory function. That is, it can be seen that the hydrogen gas concentration sensor 10 configured as shown in FIG. 1 can detect the hydrogen gas concentration and functions as a sensor. Therefore, it can be seen that the hydrogen gas concentration sensor 10 shown in FIG. 1 can be applied to liquids such as oil to detect the concentration of hydrogen gas dissolved in these liquids.
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Abstract
The present invention comprises a first electrode piece, a second electrode piece, an electrolyte in which the electrode pieces are disposed apart from each other, and a container which accommodates the first electrode piece, the second electrode piece, and the electrolyte, wherein: the first electrode piece includes a first electrode material exhibiting a standard electromotive force value of at least 0.8 V in a cell configured from H2 (-), 50 mol/m3 of H2SO4, and a substance sample (+); the second electrode includes a second electrode material exhibiting a standard electromotive force value of less than 0.8 V in a cell having the same configuration; and the first electrode piece penetrates through the electrolyte and has an end that is externally exposed from the container.
Description
本発明は、水素ガス濃度センサに関する。
The present invention relates to a hydrogen gas concentration sensor.
今後の水素エネルギー利用社会において水素爆発の危険性を払拭し安全性が高く、利便性に優れた水素エネルギー利用システムの構築が望まれる。水素ガスセンサの仕様は、大気中に漏れた水素量を瞬時に高精度で検出でき、構造がきわめて単純、信頼性が高いことが求められる。
In the future society that uses hydrogen energy, it is desirable to build a highly safe and convenient hydrogen energy utilization system that eliminates the danger of hydrogen explosions. The specifications of the hydrogen gas sensor are required to be able to instantly detect the amount of hydrogen leaked into the atmosphere with high accuracy, to have an extremely simple structure, and to be highly reliable.
一方で、自動車・重機などの水素燃料電池の制御用水素濃度センサ（水素ガスの効率利用）、発電機軸受用の潤滑油やトランスオイルなど液中用の水素濃度センサ（水素ガスの溶解量やオイル劣化による水素ガス量の検知）や腎臓透析などの医療薬液中の水素濃度センサ（水素を溶存することで治療効果を促進）、水素水など溶液中の水素濃度センサ、化学工業などでのプロセス制御用水素濃度センサの開発が望まれている。
On the other hand, hydrogen concentration sensors for controlling hydrogen fuel cells in automobiles and heavy machinery (efficient use of hydrogen gas), hydrogen concentration sensors for liquids such as lubricating oil for generator bearings and transformer oil (dissolving amount of hydrogen gas and oil detection of hydrogen gas volume due to deterioration), hydrogen concentration sensor in medical chemicals such as kidney dialysis (promotes treatment effect by dissolving hydrogen), hydrogen concentration sensor in solution such as hydrogen water, process control in chemical industry, etc. The development of a hydrogen concentration sensor for gas is desired.
従来の水素ガス濃度センサは半導体型、電離型、燃焼型などの検出方法に基づいている。これらの測定原理は「示量性の物理量」である“キャリア濃度（半導体型）”、“イオン濃度（電離型）”、あるいは“反応熱（燃焼型または燃焼させてその水蒸気圧を測定する”として間接的な検出方法で水素量を検知し、それらを電気的な量に変換してセンサとするものであった。
Conventional hydrogen gas concentration sensors are based on detection methods such as semiconductor type, ionization type, and combustion type. These measurement principles are "quantitative physical quantities" such as "carrier concentration (semiconductor type)", "ion concentration (ionization type)", or "reaction heat (combustion type or by burning and measuring the water vapor pressure"). As an indirect detection method, the amount of hydrogen is detected, and the amount of hydrogen is converted into an electric amount and used as a sensor.
したがって、高温高湿度環境下での水素濃度検知やオイルや薬液などの液体に適用することはできず、当然にこれら液体中に溶存した水素ガスの濃度の検出に適用することはできなかった。
Therefore, it cannot be applied to hydrogen concentration detection in a high temperature and high humidity environment or to liquids such as oil and chemical solutions, and naturally it cannot be applied to detect the concentration of hydrogen gas dissolved in these liquids.
Therefore, it cannot be applied to hydrogen concentration detection in a high temperature and high humidity environment or to liquids such as oil and chemical solutions, and naturally it cannot be applied to detect the concentration of hydrogen gas dissolved in these liquids.
検出時間を短縮化する水素ガス濃度センサとしては、例えば、互いに水素に対する化学ポテンシャルが異なる材料からなる第１の電極及び第２の電極と、これらの電極と接触する電解質とを備え、これら電極間に発生する起電力値に基づいて水素ガスを検出する水素ガスセンサが提案されている（特許文献１）。
A hydrogen gas concentration sensor for shortening the detection time includes, for example, a first electrode and a second electrode made of materials having different chemical potentials with respect to hydrogen, and an electrolyte in contact with these electrodes. A hydrogen gas sensor has been proposed that detects hydrogen gas based on the value of the electromotive force generated in (Patent Document 1).
しかしながら、特許文献１に記載の当該水素ガスセンサは、第１電極、第２電極及び電解質が外皮で覆われているため、当該水素ガスセンサを液体中の溶存水素ガス濃度を測定するようにするためには、少なくとも検出電極である第１電極を外皮から露出させて上記液体中に浸漬させる必要がある一方、電解質は液体からシールしなければならない。したがって、水素ガスセンサの構造が複雑になるとともに、シール方法に技術的及び経済的な課題があった。
However, in the hydrogen gas sensor described in Patent Document 1, the first electrode, the second electrode and the electrolyte are covered with an outer skin. requires that at least the first electrode, which is the sensing electrode, be exposed from the skin and immersed in the liquid, while the electrolyte must be sealed from the liquid. Therefore, the structure of the hydrogen gas sensor becomes complicated, and the sealing method poses technical and economic problems.
本発明は、高温高湿度環境下、化学工業などでの特殊ガス中や液体中などの環境に存在する水素ガス濃度を検出することが可能な新規な構成の水素ガス濃度センサを提供することを目的とする。
An object of the present invention is to provide a hydrogen gas concentration sensor of a novel configuration capable of detecting the concentration of hydrogen gas present in environments such as special gases and liquids used in the chemical industry under high-temperature and high-humidity environments. aim.
本発明は、以下に示す通りである。
（１）第１電極片及び第２電極片と、これら電極片が離隔して配設された電解質と、前記第１電極片、前記第２電極片及び前記電解質を収容する容器と、を備え、前記第１電極片は、Ｈ2（－）｜５０ｍｏｌ／ｍ3Ｈ2ＳＯ4｜物質試料（＋）で構成したセルの標準起電力値が０．８Ｖ以上の値を示す第１電極材料を含み、前記第２電極は、同構成でのセルでの標準起電力値が０．８Ｖ未満の値を示す第２電極材料を含み、前記第１電極片は、前記固体電解質を貫通し、端部が前記容器から外部に露出していることを特徴とする、水素ガス濃度センサ。
（２）前記第１電極材料は、白金、白金合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、（１）に記載の水素ガス濃度センサ。
（３）前記第１電極材料は、パラジウム、パラジウム合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、（１）に記載の水素ガス濃度センサ。
（４）前記第２電極材料は、タングステン、タングステン合金、ニッケル、ニッケル合金、チタン、チタン合金、銅、銅合金、鉄、鉄合金、アルミニウム、アルミニウム合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、（１）～（３）のいずれか１つに記載の水素ガス濃度センサ。
（５）前記容器内に収容され、前記電解質に配設された温度補償用の第３電極片を備えることを特徴とする、（１）～（４）のいずれ１つに記載の水素ガス濃度センサ。 The present invention is as described below.
(1) A first electrode piece, a second electrode piece, an electrolyte in which these electrode pieces are spaced apart, and a container that accommodates the first electrode piece, the second electrode piece, and the electrolyte. , the first electrode piece is a first electrode material exhibiting a standard electromotive force value of 0.8 V or more in a cell composed of H 2 (−)|50 mol/m 3 H 2 SO 4 | material sample (+) wherein the second electrode includes a second electrode material that exhibits a standard electromotive force value of less than 0.8 V in a cell with the same configuration, the first electrode piece penetrates the solid electrolyte, A hydrogen gas concentration sensor, wherein an end portion is exposed outside from the container.
(2) The hydrogen gas concentration sensor according to (1), wherein the first electrode material includes at least one of platinum, platinum alloys, and materials containing these.
(3) The hydrogen gas concentration sensor according to (1), wherein the first electrode material includes at least one of palladium, a palladium alloy, and materials containing these.
(4) The second electrode material includes at least one of tungsten, tungsten alloys, nickel, nickel alloys, titanium, titanium alloys, copper, copper alloys, iron, iron alloys, aluminum, aluminum alloys, and materials containing these. The hydrogen gas concentration sensor according to any one of (1) to (3), characterized by:
(5) The hydrogen gas concentration according to any one of (1) to (4), which is housed in the container and provided with a third electrode piece for temperature compensation disposed in the electrolyte. sensor.
（１）第１電極片及び第２電極片と、これら電極片が離隔して配設された電解質と、前記第１電極片、前記第２電極片及び前記電解質を収容する容器と、を備え、前記第１電極片は、Ｈ2（－）｜５０ｍｏｌ／ｍ3Ｈ2ＳＯ4｜物質試料（＋）で構成したセルの標準起電力値が０．８Ｖ以上の値を示す第１電極材料を含み、前記第２電極は、同構成でのセルでの標準起電力値が０．８Ｖ未満の値を示す第２電極材料を含み、前記第１電極片は、前記固体電解質を貫通し、端部が前記容器から外部に露出していることを特徴とする、水素ガス濃度センサ。
（２）前記第１電極材料は、白金、白金合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、（１）に記載の水素ガス濃度センサ。
（３）前記第１電極材料は、パラジウム、パラジウム合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、（１）に記載の水素ガス濃度センサ。
（４）前記第２電極材料は、タングステン、タングステン合金、ニッケル、ニッケル合金、チタン、チタン合金、銅、銅合金、鉄、鉄合金、アルミニウム、アルミニウム合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、（１）～（３）のいずれか１つに記載の水素ガス濃度センサ。
（５）前記容器内に収容され、前記電解質に配設された温度補償用の第３電極片を備えることを特徴とする、（１）～（４）のいずれ１つに記載の水素ガス濃度センサ。 The present invention is as described below.
(1) A first electrode piece, a second electrode piece, an electrolyte in which these electrode pieces are spaced apart, and a container that accommodates the first electrode piece, the second electrode piece, and the electrolyte. , the first electrode piece is a first electrode material exhibiting a standard electromotive force value of 0.8 V or more in a cell composed of H 2 (−)|50 mol/m 3 H 2 SO 4 | material sample (+) wherein the second electrode includes a second electrode material that exhibits a standard electromotive force value of less than 0.8 V in a cell with the same configuration, the first electrode piece penetrates the solid electrolyte, A hydrogen gas concentration sensor, wherein an end portion is exposed outside from the container.
(2) The hydrogen gas concentration sensor according to (1), wherein the first electrode material includes at least one of platinum, platinum alloys, and materials containing these.
(3) The hydrogen gas concentration sensor according to (1), wherein the first electrode material includes at least one of palladium, a palladium alloy, and materials containing these.
(4) The second electrode material includes at least one of tungsten, tungsten alloys, nickel, nickel alloys, titanium, titanium alloys, copper, copper alloys, iron, iron alloys, aluminum, aluminum alloys, and materials containing these. The hydrogen gas concentration sensor according to any one of (1) to (3), characterized by:
(5) The hydrogen gas concentration according to any one of (1) to (4), which is housed in the container and provided with a third electrode piece for temperature compensation disposed in the electrolyte. sensor.
本発明によれば、高温高湿度環境下、化学工業などの特殊ガス中や液体中に存在する水素ガス濃度を検出することが可能な新規な構成の水素ガス濃度センサを提供することができる。
According to the present invention, it is possible to provide a hydrogen gas concentration sensor with a novel configuration that is capable of detecting the concentration of hydrogen gas in special gases and liquids used in the chemical industry under high-temperature and high-humidity environments.
図１は、本実施形態における水素ガス濃度センサの概略構成図である。
FIG. 1 is a schematic configuration diagram of a hydrogen gas concentration sensor according to this embodiment.
図１に示すように、本実施形態の水素ガス濃度センサ１０は、線状の第１電極片１１及び線状の第２電極片１２と、これら電極片が離隔して配設された電解質１４と、第１電極片１１，第２電極片１２及び電解質１４とを収容する、一端が密閉された容器１５とを備えている。
As shown in FIG. 1, the hydrogen gas concentration sensor 10 of this embodiment includes a first linear electrode piece 11, a second linear electrode piece 12, and an electrolyte 14 in which these electrode pieces are spaced apart. , and a container 15 with one end sealed to accommodate the first electrode piece 11 , the second electrode piece 12 and the electrolyte 14 .
なお、容器１５は、その先端部を測定したい系の中に挿入し配設されているものである。従って、容器１５の内部は測定したい系とガス的に絶縁状態となるが、外界からの湿度などの影響を受けないように、この内部をシールして使用することが望ましい。
It should be noted that the container 15 is arranged such that its tip is inserted into the system to be measured. Therefore, the inside of the container 15 is gas-insulated from the system to be measured.
また、第１電極片１１は水素ガス検出電極として機能するため、その先端部は、電解質１４の密閉部を貫通して、容器１５の外部に露出している。なお、第１電極片１１の容器１５の貫通部分は溶融封止されている。
In addition, since the first electrode piece 11 functions as a hydrogen gas detection electrode, its tip penetrates through the sealed portion of the electrolyte 14 and is exposed to the outside of the container 15 . The portion of the first electrode piece 11 that penetrates the container 15 is melt-sealed.
但し、以下に説明するように、第２電極片１２は相対的に化学ポテンシャルの低い材料から構成されており、水素ガスの検出には影響しないので、第２電極片１２の端部も第１電極片１１と同様に、容器１５の密閉部から外部に露出させることができる。しかしながら、一般には、再度の溶融封止が必要となり、水素ガス濃度センサ１０の構成及び作製工程が煩雑となるため、容器１５外には露出させないことが好ましい。
However, as described below, the second electrode piece 12 is made of a material with a relatively low chemical potential and does not affect the detection of hydrogen gas. Like the electrode piece 11 , it can be exposed to the outside from the sealed portion of the container 15 . However, in general, it is preferable not to expose the sensor 15 to the outside of the container 15 , because re-melting and sealing is generally required, which complicates the structure and manufacturing process of the hydrogen gas concentration sensor 10 .
また、本実施形態の水素ガス濃度センサ１０は、環境温度に依存して検出感度が変化するので、当該環境温度による影響を除去すべく、線状の温度補償用第３電極片１３が配設されている。この第３電極片１３も電解質１４に対して、第１電極片１１及び第２電極片１２と離隔するようにして配設されている。
Further, since the detection sensitivity of the hydrogen gas concentration sensor 10 of the present embodiment changes depending on the environmental temperature, the linear temperature compensating third electrode piece 13 is arranged to eliminate the influence of the environmental temperature. It is The third electrode piece 13 is also arranged with respect to the electrolyte 14 so as to be separated from the first electrode piece 11 and the second electrode piece 12 .
また、第１電極片１１、第２電極片１２及び第３電極片１３は、水素ガス濃度の検出に伴う起電力を測定すべく、容器１５の密閉部と反対側の容器１５の後端開口部より、容器１５の外方に延在するようにして配設されている。
Also, the first electrode piece 11, the second electrode piece 12 and the third electrode piece 13 are connected to the rear end opening of the container 15 on the side opposite to the sealed portion of the container 15 in order to measure the electromotive force associated with the detection of the hydrogen gas concentration. It is arranged so as to extend outward from the container 15 from the part.
第１電極片１１は、水素ガスに対する検出電極として機能し、水素ガスと接触することによって、（原子状）水素の化学ポテンシャルが大きく変化する。第２電極片１２は、水素ガスに対する基準電極として機能し、水素ガスと接触することによって、その化学ポテンシャルがほとんど変化しないか、変化するとしても極微小である。
The first electrode piece 11 functions as a detection electrode for hydrogen gas, and when it comes into contact with hydrogen gas, the chemical potential of (atomic) hydrogen changes greatly. The second electrode piece 12 functions as a reference electrode for hydrogen gas, and when it comes into contact with hydrogen gas, its chemical potential hardly changes or changes very little.
第１電極片１１は、相対的に化学ポテンシャルの高い第１電極材料から構成することができ、具体的にはＨ2（－）｜５０ｍｏｌ／ｍ3Ｈ2ＳＯ4｜物質試料（＋）で構成したセルの標準起電力値が０．８Ｖ以上の値を示す第１電極材料を含む。
The first electrode piece 11 can be made of a first electrode material with a relatively high chemical potential, specifically H 2 (−)|50 mol/m 3 H 2 SO 4 |substance sample (+). It includes a first electrode material that exhibits a standard electromotive force value of 0.8 V or more in the constructed cell.
上述した材料としては、白金、白金合金等の、相対的に水素ガスに対する吸着活性度の高い材料を挙げることができる。第１電極片１１は、これら材料自身から構成することもできるが、これらの材料を所定の基体上に担持させて用いることができる。但し、本発明の範疇を逸脱せず、水素ガスに対する検出電極として機能する限り、任意の態様で使用することができる。
Examples of the above materials include materials with relatively high adsorption activity for hydrogen gas, such as platinum and platinum alloys. Although the first electrode piece 11 can be composed of these materials themselves, these materials can be used by carrying them on a predetermined substrate. However, it can be used in any manner as long as it functions as a detection electrode for hydrogen gas without departing from the scope of the present invention.
また、上述した材料として、パラジウム、パラジウム合金等の、相対的に水素ガスに対する吸着活性度の高い材料から構成することもできる。上記同様に、第１電極片１１は、これら材料自身から構成することもできるが、これらの材料を所定の基体上に担持させて用いることができる。但し、本発明の範疇を逸脱せず、水素ガスに対する検出電極として機能する限り、任意の態様で使用することができる。
In addition, as the material described above, it is also possible to use a material with relatively high adsorption activity for hydrogen gas, such as palladium or a palladium alloy. In the same manner as described above, the first electrode piece 11 can be made of these materials themselves, but these materials can also be used by carrying them on a predetermined substrate. However, it can be used in any manner as long as it functions as a detection electrode for hydrogen gas without departing from the scope of the present invention.
なお、第１電極片１１を白金系の材料から構成した場合は、水素分子を解離することから、第１電極片１１に吸着した水素ガスの離脱が早く、燃料電池の制御用センサや医療薬液等に溶存する水素ガス濃度センサなど、応答性の早い水素ガス濃度センサの検出電極として適している。
When the first electrode piece 11 is made of a platinum-based material, the hydrogen molecules are dissociated, so that the hydrogen gas adsorbed on the first electrode piece 11 is quickly detached. It is suitable as a detection electrode for a hydrogen gas concentration sensor that responds quickly, such as a hydrogen gas concentration sensor dissolved in water.
一方、第１電極片１１をパラジウム系の材料から構成した場合は、水素分圧に応じた水素量を固溶するが、固溶水素は抜けづらいという性質があり、水素ガス検出後の回復に時間を要する。したがって、第１電極片１１をパラジウム系の材料から構成した場合、当該第１電極片１１はメモリ機能を有するので、例えばトランスオイルの劣化を確認するのに適した検出電極として適用できる。
On the other hand, when the first electrode piece 11 is made of a palladium-based material, the amount of hydrogen corresponding to the hydrogen partial pressure dissolves in solid solution, but the dissolved hydrogen is difficult to escape. It takes time. Therefore, when the first electrode piece 11 is made of a palladium-based material, the first electrode piece 11 has a memory function and can be applied as a detection electrode suitable for checking deterioration of transformer oil, for example.
第２電極片１２は、相対的に化学ポテンシャルの低い材料から構成することができ、具体的には、Ｈ2（－）｜５０ｍｏｌ／ｍ3Ｈ2ＳＯ4｜物質試料（＋）で構成したセルの標準起電力値が０．８Ｖ未満の値を示す第２電極材料を含む。
The second electrode piece 12 can be made of a material with a relatively low chemical potential, specifically H 2 (−)|50 mol/m 3 H 2 SO 4 |material sample (+). The second electrode material exhibits a cell standard electromotive force value of less than 0.8V.
上述した材料としては、タングステン、タングステン合金、ニッケル、ニッケル合金、チタン、チタン合金、銅、銅合金、鉄、鉄合金、アルミニウム、アルミニウム合金及び有機導電材料などの、相対的に水素ガスに対する吸着活性度合いの低い材料を挙げることができる。但し、本発明の範疇を逸脱せず、水素ガスに対する基準電極として機能する限り、任意の態様で使用することができる。
The materials mentioned above include tungsten, tungsten alloys, nickel, nickel alloys, titanium, titanium alloys, copper, copper alloys, iron, iron alloys, aluminum, aluminum alloys and organic conductive materials, which have relatively high adsorption activity for hydrogen gas. Low degree materials can be mentioned. However, it can be used in any manner as long as it functions as a reference electrode for hydrogen gas without departing from the scope of the present invention.
なお、第３電極片１３は、温度補償用の電極片であり、水素ガス濃度センサ１０の環境温度、すなわち検出電極である第１電極片１１の環境温度変化を相殺するために配設されているものであるので、第１電極片１１と同じ材料から構成することが好ましい。
The third electrode piece 13 is an electrode piece for temperature compensation, and is arranged to offset changes in the environmental temperature of the hydrogen gas concentration sensor 10, that is, the environmental temperature of the first electrode piece 11, which is the detection electrode. Therefore, it is preferable to use the same material as the first electrode piece 11 .
また、電解質１４は、燐タングステン酸などの、第１電極２１及び第２電極２２との密着性に優れた電解質から構成することができる。電解質１４は、燐タングステンなどの電解質材料に加えてグラスウールなどの構造補強材を含むことができる。この場合、電解質１４の強度を増大させることができるとともに、第１電極片１１及び第２電極片１２との密着性をさらに増大させることができる。
Further, the electrolyte 14 can be composed of an electrolyte having excellent adhesion to the first electrode 21 and the second electrode 22, such as phosphotungstic acid. Electrolyte 14 may include structural reinforcements such as glass wool in addition to electrolyte materials such as phosphotungsten. In this case, the strength of the electrolyte 14 can be increased, and the adhesion between the first electrode piece 11 and the second electrode piece 12 can be further increased.
容器１５は、第１電極片１１及び第２電極片１２との絶縁を担保すべく、ガラスや樹脂、セラミックス等から構成することが好ましい。
The container 15 is preferably made of glass, resin, ceramics, or the like in order to ensure insulation between the first electrode piece 11 and the second electrode piece 12 .
なお、容器１５を金属等の電気伝導性の材料から構成した場合は、第１電極片１１を樹脂やセラミック被覆等して容器１５と絶縁することが好ましい。
When the container 15 is made of an electrically conductive material such as metal, it is preferable to insulate the first electrode piece 11 from the container 15 by coating it with resin or ceramic.
本実施形態の水素ガス濃度センサ１０によれば、第１電極片１１及び第２電極片１２と、これら電極片が離隔して配設された電解質１４と、第１電極片１１、第２電極片１２及び電解質１４を収容する容器１５と、を備え、第１電極片１１は、Ｈ2（－）｜５０ｍｏｌ／ｍ3Ｈ2ＳＯ4｜物質試料（＋）で構成したセルの標準起電力値が０．８Ｖ以上の値を示す第１電極材料を含み、第２電極片１２は、同構成でのセルでの標準起電力値が０．８Ｖ未満の値を示す第２電極材料を含み、第１電極片１１は、電解質１４を貫通し、端部が容器１５から外部に露出している。
According to the hydrogen gas concentration sensor 10 of this embodiment, the first electrode piece 11 and the second electrode piece 12, the electrolyte 14 in which these electrode pieces are separated, the first electrode piece 11 and the second electrode a container 15 containing a piece 12 and an electrolyte 14, wherein the first electrode piece 11 is a standard electromotive force of a cell composed of H 2 (−)|50 mol/m 3 H 2 SO 4 |substance sample (+) A first electrode material having a value of 0.8 V or more is included, and the second electrode piece 12 includes a second electrode material having a standard electromotive force value of less than 0.8 V in a cell with the same configuration. , the first electrode piece 11 penetrates the electrolyte 14 and has an end exposed outside from the container 15 .
したがって、溶存する水素ガス濃度を検出するためには、水素ガス濃度センサ１０の容器１５から露出した第１電極片１１を、溶存水素ガスを含む液体中に浸漬させればよい。この際に、容器１５の先端部分が液体中に浸漬しても、電解質１４自体は容器１５内に収容され、密封されているので、液体に浸漬されることがない。すなわち、水素ガス濃度センサ１０は、液体中に浸漬された検出電極である第１電極片１１と基準電極である第２電極片１２とによって、液体中に溶存した水素ガス濃度を検出することができる。同様に、高温高湿度環境下や化学工業などの特殊ガスの中の水素ガス濃度を検出することができる。
Therefore, in order to detect the dissolved hydrogen gas concentration, the first electrode piece 11 exposed from the container 15 of the hydrogen gas concentration sensor 10 should be immersed in a liquid containing dissolved hydrogen gas. At this time, even if the tip portion of the container 15 is immersed in the liquid, the electrolyte 14 itself is housed and sealed in the container 15 and is therefore not immersed in the liquid. That is, the hydrogen gas concentration sensor 10 can detect the concentration of hydrogen gas dissolved in the liquid by means of the first electrode piece 11, which is the detection electrode, and the second electrode piece 12, which is the reference electrode, both of which are immersed in the liquid. can. Similarly, it is possible to detect the concentration of hydrogen gas in special gases such as those used in high-temperature, high-humidity environments or in the chemical industry.
このように、本実施形態の水素ガス濃度センサ１０によれば、その先端部を液体中に浸漬させ、検出電極である第１電極片１１を当該液体中に浸漬すれば足りる。したがって、従来のシール型水素ガス濃度センサのように、少なくとも検出電極である第１電極を外皮から露出させて液体中に浸漬させ、電解質を外皮によって液体からシールする必要がない。すなわち、極めてシンプルな構成で、水素ガス濃度を検出することができる。
Thus, according to the hydrogen gas concentration sensor 10 of this embodiment, it is sufficient to immerse the tip portion in the liquid and immerse the first electrode piece 11 as the detection electrode in the liquid. Therefore, unlike the conventional sealed hydrogen gas concentration sensor, it is not necessary to expose at least the first electrode, which is the detection electrode, from the outer skin and immerse it in the liquid, and to seal the electrolyte from the liquid with the outer skin. That is, the hydrogen gas concentration can be detected with an extremely simple configuration.
なお、本実施形態の水素ガス濃度センサ１０の水素濃度は、第１電極片１１及び第２電極片１２間に発生する起電力によって検出することになるが、当該起電力は以下の関係式に基づいて生成される。
The hydrogen concentration of the hydrogen gas concentration sensor 10 of this embodiment is detected by the electromotive force generated between the first electrode piece 11 and the second electrode piece 12. The electromotive force is expressed by the following relational expression. generated based on
なお、第３電極片１３による温度補償は、
で表され、このＥ値を上述のＥＭＦ値から差し引くことにより実行することができる。但し、水素濃度が１％を超えるような濃度（ｎが０．０１以上）の場合は、上記Ｅ値は極めて小さい値となるので、温度補償は考慮する必要はなく、第３電極片１３自体も省略することができる。
The temperature compensation by the
and can be done by subtracting this E value from the EMF value above. However, when the hydrogen concentration exceeds 1% (n is 0.01 or more), the E value becomes a very small value, so temperature compensation does not need to be considered, and the
以下に実施例を挙げて本発明をより具体的に説明するが、本発明はこれらに限定されない。
The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these.
図１に示す水素ガス濃度センサ１０を準備し、簡易的に水素ガスの検出試験を実施した。なお、第１電極片１１は直径０．２ｍｍの白金線及びパラジウム線を使用し、第２電極片１２は直径０．２ｍｍのタングステン線を使用した。また、簡略化のために第３電極片１３は省略した。
A hydrogen gas concentration sensor 10 shown in FIG. 1 was prepared, and a simple hydrogen gas detection test was carried out. A platinum wire and a palladium wire with a diameter of 0.2 mm were used for the first electrode piece 11, and a tungsten wire with a diameter of 0.2 mm was used for the second electrode piece 12. Also, the third electrode piece 13 is omitted for simplification.
次いで、第１電極片１１及び第２電極片１２を燐タングステン酸セシウムからなる電解質１４に０．２ｍｍの間隔をあけて配設し、さらに、第１電極片１１，第２電極片１２及び電解質１４を、直径６ｍｍ及び長さ２５ｍｍのガラス管１５内に収納して配設し、当該ガラス管１５の先端部より、第１電極片１１を３ｍｍの長さで露出させるとともに溶融封止した。なお、露出部分は根元部分で切断してもよい。電解質と電極の配置にも特別な制約はない。
Next, the first electrode piece 11 and the second electrode piece 12 are arranged on the electrolyte 14 made of cesium phosphotungstate with a gap of 0.2 mm. 14 was housed in a glass tube 15 having a diameter of 6 mm and a length of 25 mm, and the first electrode piece 11 was exposed with a length of 3 mm from the tip of the glass tube 15 and melt-sealed. Note that the exposed portion may be cut off at the root portion. There are also no special restrictions on the arrangement of the electrolyte and electrodes.
次いで、図１に示すように、ガラス管１５の後端側から第１電極片１１及び第２電極片１２を露出させ、水素ガス濃度の検出による起電力を計測できるようにした。なお、この計測部分は、湿度などから保護するように、シールすることが望ましい。
Next, as shown in FIG. 1, the first electrode piece 11 and the second electrode piece 12 were exposed from the rear end side of the glass tube 15 so that the electromotive force could be measured by detecting the hydrogen gas concentration. In addition, it is desirable to seal this measuring portion so as to protect it from humidity and the like.
図２は、第１電極片１１として白金線を用いた場合の検出電圧（Ｖ）であり、図３は、第１電極片１１としてパラジウム線を用いた場合の検出電圧（Ｖ）である。
2 shows the detected voltage (V) when a platinum wire is used as the first electrode piece 11, and FIG. 3 shows the detected voltage (V) when a palladium wire is used as the first electrode piece 11. FIG.
なお、水素ガス濃度はガラス容器１５が挿入できるような開口が形成された密閉容器内に水素ガスを充填して容器内の水素濃度を調整し、検出起電力はガラス管１５の後端開口部において計測した。
The hydrogen gas concentration was adjusted by filling hydrogen gas into a sealed container having an opening for inserting the glass container 15, and the detected electromotive force was measured at the rear end opening of the glass tube 15. Measured at
図２に示すように、第１電極片１１として白金線を用いた場合は、水素ガスを検出することにより、検出電圧が０．４Ｖから０．０３Ｖまで減少するが、水素ガスとの接触を遮断すると、直ちに起電力が回復して０．４Ｖにまで回復することが分かる。すなわち、水素ガスの離脱が早く、応答性の早い水素ガス濃度センサの検出電極として適していることが分かる。なお、燃料電池制御センサを想定し温度８５℃の測定結果とした。
As shown in FIG. 2, when a platinum wire is used as the first electrode piece 11, the detection voltage decreases from 0.4 V to 0.03 V by detecting hydrogen gas. It can be seen that the electromotive force immediately recovers to 0.4 V when the voltage is cut off. That is, it can be seen that hydrogen gas desorbs quickly and is suitable as a detection electrode for a hydrogen gas concentration sensor with fast response. Assuming a fuel cell control sensor, the measurement result was obtained at a temperature of 85°C.
事例では、水素ガスに対する応答性の比較のため、水素濃度１０％とした。なお、第１電極片１１として白金線を用いた測定は、ＥＭＦ型水素センサの特徴であるセンサの自発起電力の値はエレクトロメーターによりガラス管１５の後端開口部において計測した。
In the example, the hydrogen concentration was set to 10% to compare the responsiveness to hydrogen gas. In the measurement using the platinum wire as the first electrode piece 11, the value of the spontaneous electromotive force of the sensor, which is a feature of the EMF type hydrogen sensor, was measured at the rear end opening of the glass tube 15 with an electrometer.
一方、図３に示すように、第１電極片１１としてパラジウム線を用いた場合は、水素ガスを１２００秒の処で検出すると、検出電圧が０．１５Ｖから０．１Ｖまで減少し水素濃度に応じた検出電圧値となる。水素ガスを３０００秒の処で除去しても元の出力値（０．１５Ｖ）に戻るためには３０００秒（５０分）以上を要することが分かる。すなわち、メモリ機能を有し、例えばトランスオイルの劣化を確認するのに適していることが分かる。なお、室温での利用を想定し温度２０℃の測定結果とした。
On the other hand, as shown in FIG. 3, when a palladium wire is used as the first electrode piece 11, when hydrogen gas is detected at 1200 seconds, the detected voltage decreases from 0.15 V to 0.1 V, and the hydrogen concentration The corresponding detection voltage value is obtained. It can be seen that even if the hydrogen gas is removed at 3000 seconds, it takes 3000 seconds (50 minutes) or more to return to the original output value (0.15 V). That is, it has a memory function and is suitable for checking the deterioration of transformer oil, for example. In addition, the measurement results at a temperature of 20° C. were assumed to be used at room temperature.
次いで、第１電極片１１として同一の白金線を用い、ガラス容器１５が挿入できるような開口が形成された密閉容器内に水素ガスを充填してその濃度を温度８５℃で水素濃度を０～４０体積％まで変化させ、その際の検出電圧を計測した。なお、検出電圧はガラス管１５の後端開口部において計測した。測定は上述のエレクトロメーターを用いた。
Next, using the same platinum wire as the first electrode piece 11, hydrogen gas is filled in a sealed container having an opening for inserting the glass container 15, and the hydrogen concentration is adjusted to 0 to 0 at a temperature of 85 ° C. It was changed to 40% by volume, and the detected voltage at that time was measured. The detected voltage was measured at the rear end opening of the glass tube 15 . The above-mentioned electrometer was used for the measurement.
図４に示すように、第１電極片１１として白金線を用いた場合は、水素ガス濃度の上昇につれて検出電圧が減少することが分かる。すなわち、図１に示す構成の水素ガス濃度センサ１０が水素ガス濃度を検出することができ、センサとして機能することが分かる。したがって、図１に示す水素ガス濃度センサ１０をオイルなどの液体に適用し、これら液体中に溶存した水素ガスの濃度の検出に適用できることが分かる。
As shown in FIG. 4, when a platinum wire is used as the first electrode piece 11, it can be seen that the detected voltage decreases as the hydrogen gas concentration increases. That is, it can be seen that the hydrogen gas concentration sensor 10 configured as shown in FIG. 1 can detect the hydrogen gas concentration and functions as a sensor. Therefore, it can be seen that the hydrogen gas concentration sensor 10 shown in FIG. 1 can be applied to liquids such as oil to detect the concentration of hydrogen gas dissolved in these liquids.
次いで、第１電極片１１として同一のパラジウム線を用い、ガラス容器１５が挿入できるような開口が形成された密閉容器内に水素ガスを充填してその濃度を温度２０℃で水素濃度を０～２０体積％まで変化させ、その際の検出電圧を計測した。なお、検出電圧はガラス管１５の後端開口部において計測した。測定は上述のエレクトロメーターを用いた。
Next, using the same palladium wire as the first electrode piece 11, hydrogen gas is filled in a sealed container having an opening for inserting the glass container 15, and the hydrogen concentration is adjusted to 0 to 0 at a temperature of 20 ° C. It was changed to 20% by volume, and the detection voltage at that time was measured. The detected voltage was measured at the rear end opening of the glass tube 15 . The above-mentioned electrometer was used for the measurement.
図５に示すように、第１電極片１１としてパラジウム線を用いた場合は、そのメモリ機能を維持しながら、水素ガス濃度の上昇につれて検出電圧も上昇することが分かる。すなわち、図１に示す構成の水素ガス濃度センサ１０が水素ガス濃度を検出することができ、センサとして機能することが分かる。したがって、図１に示す水素ガス濃度センサ１０をオイルなどの液体に適用し、これら液体中に溶存した水素ガスの濃度の検出に適用できることが分かる。
As shown in FIG. 5, when a palladium wire is used as the first electrode piece 11, the detection voltage increases as the hydrogen gas concentration increases while maintaining its memory function. That is, it can be seen that the hydrogen gas concentration sensor 10 configured as shown in FIG. 1 can detect the hydrogen gas concentration and functions as a sensor. Therefore, it can be seen that the hydrogen gas concentration sensor 10 shown in FIG. 1 can be applied to liquids such as oil to detect the concentration of hydrogen gas dissolved in these liquids.
以上、本発明のいくつかの実施形態を説明したが、これらの実施形態は例として掲示したものであり、発明の範囲を限定することは意図していない。これら新規な実施形態は、その他の様々な形態で実施されることが可能であり、発明の要旨を逸脱しない範囲で、種々の省略、置き換え、変更を行うことができる。これら実施形態やその変形は、発明の範囲や要旨に含まれるとともに、特許請求の範囲に記載された発明とその均等の範囲に含まれる。
Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof.
１０ 水素ガス濃度センサ
１１ 第１電極片
１２ 第２電極片
１３ 第３電極片
１４ 電解質
１５ 容器 10 hydrogengas concentration sensor 11 first electrode piece 12 second electrode piece 13 third electrode piece 14 electrolyte 15 container
１１ 第１電極片
１２ 第２電極片
１３ 第３電極片
１４ 電解質
１５ 容器 10 hydrogen
Claims (5)
- 第１電極片及び第２電極片と、これら電極片が離隔して配設された電解質と、前記第１電極片、前記第２電極片及び前記電解質を収容する容器と、を備え、
前記第１電極片は、Ｈ2（－）｜５０ｍｏｌ／ｍ3Ｈ2ＳＯ4｜物質試料（＋）で構成したセルの標準起電力値が０．８Ｖ以上の値を示す第１電極材料を含み、
前記第２電極は、同構成でのセルでの標準起電力値が０．８Ｖ未満の値を示す第２電極材料を含み、
前記第１電極片は、前記電解質を貫通し、端部が前記容器から外部に露出していることを特徴とする、水素ガス濃度センサ。 a first electrode piece and a second electrode piece, an electrolyte in which the electrode pieces are spaced apart, and a container for housing the first electrode piece, the second electrode piece and the electrolyte,
The first electrode piece is made of a first electrode material exhibiting a standard electromotive force value of 0.8 V or more in a cell composed of H 2 (−)|50 mol/m 3 H 2 SO 4 | material sample (+). including
The second electrode includes a second electrode material that exhibits a standard electromotive force value of less than 0.8 V in a cell with the same configuration,
The hydrogen gas concentration sensor, wherein the first electrode piece penetrates the electrolyte and has an end exposed outside from the container. - 前記第１電極材料は、白金、白金合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、請求項１に記載の水素ガス濃度センサ。 The hydrogen gas concentration sensor according to claim 1, wherein the first electrode material includes at least one of platinum, platinum alloys, and materials containing these.
- 前記第１電極材料は、パラジウム、パラジウム合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、請求項１に記載の水素ガス濃度センサ。 The hydrogen gas concentration sensor according to claim 1, wherein the first electrode material includes at least one of palladium, a palladium alloy, and materials containing these.
- 前記第２電極材料は、タングステン、タングステン合金、ニッケル、ニッケル合金、チタン、チタン合金、銅、銅合金、鉄、鉄合金、アルミニウム、アルミニウム合金及びこれらを含む材料の少なくとも１つを含むことを特徴とする、請求項１に記載の水素ガス濃度センサ。 The second electrode material includes at least one of tungsten, tungsten alloys, nickel, nickel alloys, titanium, titanium alloys, copper, copper alloys, iron, iron alloys, aluminum, aluminum alloys, and materials containing these. The hydrogen gas concentration sensor according to claim 1, wherein:
- 前記容器内に収容され、前記電解質に配設された温度補償用の第３電極片を備えることを特徴とする、請求項１に記載の水素ガス濃度センサ。 The hydrogen gas concentration sensor according to claim 1, further comprising a temperature-compensating third electrode piece housed in the container and disposed on the electrolyte.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005080957A1 (en) * | 2004-02-19 | 2005-09-01 | Niigata Tlo Corporation | Hydrogen gas sensor |
| JP2007047124A (en) * | 2005-08-12 | 2007-02-22 | Niigata Tlo:Kk | Hydrogen gas sensor |
| JP2008196903A (en) * | 2007-02-09 | 2008-08-28 | Niigata Univ | Hydrogen quantity sensor |
| JP2009243962A (en) * | 2008-03-28 | 2009-10-22 | Niigata Univ | Hydrogen gas sensor |
| JP2010230620A (en) * | 2009-03-30 | 2010-10-14 | Niigata Univ | High concentration hydrogen gas sensor |
| WO2011145150A1 (en) * | 2010-05-21 | 2011-11-24 | 国立大学法人新潟大学 | Hydrogen gas sensor |
| JP2012163506A (en) * | 2011-02-09 | 2012-08-30 | Gunze Ltd | In-oil hydrogen detection sensor |
| JP2017044576A (en) * | 2015-08-26 | 2017-03-02 | 国立研究開発法人産業技術総合研究所 | Gas sensor and method of detecting gas |
-
2022
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Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005080957A1 (en) * | 2004-02-19 | 2005-09-01 | Niigata Tlo Corporation | Hydrogen gas sensor |
| JP2007047124A (en) * | 2005-08-12 | 2007-02-22 | Niigata Tlo:Kk | Hydrogen gas sensor |
| JP2008196903A (en) * | 2007-02-09 | 2008-08-28 | Niigata Univ | Hydrogen quantity sensor |
| JP2009243962A (en) * | 2008-03-28 | 2009-10-22 | Niigata Univ | Hydrogen gas sensor |
| JP2010230620A (en) * | 2009-03-30 | 2010-10-14 | Niigata Univ | High concentration hydrogen gas sensor |
| WO2011145150A1 (en) * | 2010-05-21 | 2011-11-24 | 国立大学法人新潟大学 | Hydrogen gas sensor |
| JP2012163506A (en) * | 2011-02-09 | 2012-08-30 | Gunze Ltd | In-oil hydrogen detection sensor |
| JP2017044576A (en) * | 2015-08-26 | 2017-03-02 | 国立研究開発法人産業技術総合研究所 | Gas sensor and method of detecting gas |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024090472A1 (en) * | 2022-10-27 | 2024-05-02 | 株式会社新潟Tlo | Hydrogen gas concentration sensor |
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