JPS6383661A - Method for measuring humidity by using solid electrolyte - Google Patents
Method for measuring humidity by using solid electrolyteInfo
- Publication number
- JPS6383661A JPS6383661A JP61227960A JP22796086A JPS6383661A JP S6383661 A JPS6383661 A JP S6383661A JP 61227960 A JP61227960 A JP 61227960A JP 22796086 A JP22796086 A JP 22796086A JP S6383661 A JPS6383661 A JP S6383661A
- Authority
- JP
- Japan
- Prior art keywords
- solid electrolyte
- anode
- ion conductivity
- cathode
- oxygen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000007784 solid electrolyte Substances 0.000 title claims abstract description 15
- 238000000034 method Methods 0.000 title claims description 4
- 239000001301 oxygen Substances 0.000 claims abstract description 25
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 25
- 239000007789 gas Substances 0.000 claims abstract description 14
- 238000009792 diffusion process Methods 0.000 claims abstract description 11
- GPRLSGONYQIRFK-UHFFFAOYSA-N hydron Chemical compound [H+] GPRLSGONYQIRFK-UHFFFAOYSA-N 0.000 claims abstract description 7
- -1 oxygen ion Chemical class 0.000 claims description 15
- 239000000969 carrier Substances 0.000 claims description 2
- 238000000691 measurement method Methods 0.000 claims description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 abstract description 4
- 238000005259 measurement Methods 0.000 abstract description 3
- 229910002761 BaCeO3 Inorganic materials 0.000 abstract description 2
- 238000000354 decomposition reaction Methods 0.000 abstract description 2
- 229910052697 platinum Inorganic materials 0.000 abstract description 2
- 238000005868 electrolysis reaction Methods 0.000 abstract 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 5
- 238000000862 absorption spectrum Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000003792 electrolyte Substances 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
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
- G01N27/407—Cells and probes with solid electrolytes for investigating or analysing gases
- G01N27/4073—Composition or fabrication of the solid electrolyte
- G01N27/4074—Composition or fabrication of the solid electrolyte for detection of gases other than oxygen
-
- 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
- G01N27/407—Cells and probes with solid electrolytes for investigating or analysing gases
- G01N27/4071—Cells and probes with solid electrolytes for investigating or analysing gases using sensor elements of laminated structure
- G01N27/4072—Cells and probes with solid electrolytes for investigating or analysing gases using sensor elements of laminated structure characterized by the diffusion barrier
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
- H01M8/124—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte
- H01M8/1246—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte the electrolyte consisting of oxides
- H01M8/126—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte the electrolyte consisting of oxides the electrolyte containing cerium oxide
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Physics & Mathematics (AREA)
- Pathology (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Molecular Biology (AREA)
- Immunology (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- General Chemical & Material Sciences (AREA)
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Measuring Oxygen Concentration In Cells (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は気体中に含まれる水分の量、すなわち絶対湿度
を測定する方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for measuring the amount of moisture contained in a gas, that is, absolute humidity.
（従来の技術）
気体中の湿度を測定する計器類には種々あり、新しい湿
度センサも開発されているが、これら従来の湿度センサ
はほとんどすべて相対湿度を測定するものであり、絶対
湿度を測定するものとしては僅かに水の赤外線吸収スペ
クトルを利用した赤外線吸収湿度計が知られている。(Prior technology) There are various instruments that measure humidity in gas, and new humidity sensors have also been developed, but almost all of these conventional humidity sensors measure relative humidity, not absolute humidity. As a device that does this, an infrared absorption hygrometer that uses the infrared absorption spectrum of water is known.
（発明が解決しようとする問題点）
水の赤外線吸収スペクトルを利用した測定方法による場
合は比較的低濃度（ρｐｍｆ＋ＪＩ域）の水蒸気の測定
は精度よく行ない得るが、パーセントオーダの水蒸気の
濃度測定はほとんど行ない得ないのが実情である。(Problems to be Solved by the Invention) When using a measurement method that utilizes the infrared absorption spectrum of water, water vapor at a relatively low concentration (ρpmf+JI range) can be measured with high accuracy, but the concentration of water vapor on the order of percent cannot be measured. The reality is that it is almost impossible to do so.
（問題点を解決するための手段及び作用）本発明はこの
ような状況の下に種々検討の結果なされたもので、水素
イオン伝導性と酸素イオン伝導性とを合わせ持つ固体電
解質を用いて、酸素イオン伝導性のみを選択的に利用し
て湿度を測定する方法を提供するものである。例えばＢ
ａＣｅＯ３の如きペロプスカイト型酸化物からなる固体
電解質を用い、その両面に多孔性電極を設け、さらに、
アノード側に気体拡散制御層を設け、両電極間に直流電
圧を印加したとき酸素イオンをキャリヤとする電流が飽
和した限界電流から絶対湿度を検出するものである。(Means and effects for solving the problems) The present invention was developed as a result of various studies under these circumstances, and uses a solid electrolyte that has both hydrogen ion conductivity and oxygen ion conductivity. The present invention provides a method for measuring humidity by selectively utilizing only oxygen ion conductivity. For example, B
A solid electrolyte made of a perovskite oxide such as aCeO3 is used, porous electrodes are provided on both sides of the electrolyte, and further,
A gas diffusion control layer is provided on the anode side, and when a DC voltage is applied between both electrodes, the absolute humidity is detected from the limit current at which the current with oxygen ions as carriers is saturated.
（実施例）
第１図は、本発明による湿度測定に用いた湿度センサ素
子の断面図であり、１は水素イオン輸率及び酸素イオン
輸率が共に１である水素イオン伝導性と酸素イオン伝導
性とを合わせ持つ、例えばＢａＣｅＯ３（Ｄ如きペロプ
スカイト型酸化物からなる固体電解質であり、この両面
に多孔質なる白金製電極を設け、その一方をアノード２
、他方をカソード３とし、気体拡散制御層として微小孔
４が形成されたキャップ５がアノード２を蔽うように固
体電解質１に接合されたものであり、本発明による湿度
測定方法は上記の如き湿度センサを用いて湿度を測定す
るものである。(Example) FIG. 1 is a cross-sectional view of a humidity sensor element used for humidity measurement according to the present invention. It is a solid electrolyte made of a perovskite type oxide such as BaCeO3 (D), which has both properties and properties, and porous platinum electrodes are provided on both sides of the electrolyte, and one side is connected to the anode 2.
, the other is a cathode 3, and a cap 5 in which micropores 4 are formed as a gas diffusion control layer is bonded to the solid electrolyte 1 so as to cover the anode 2. Humidity is measured using a sensor.
この原理を述べると、被測定気体中においてアノード２
とカソード３との間に直流電圧を印加すると、各電極上
では次の反応が起こる。To explain this principle, the anode 2 in the gas to be measured.
When a DC voltage is applied between the cathode 3 and the cathode 3, the following reaction occurs on each electrode.
カソード ＨｚＯ＋２ｅ−−’８２ ＋Ｏ”−＋１
）アノード Ｈ２０→１八Ｑ２＋’ｌＨ”
ｆ２１しかし、アノードでのＨｔＯの分解は気体拡散制
御層としてのキャップ５の微小孔４によって抑制される
ので酸素イオン（Ｏ２−）に比して水素イオン（Ｈ゛）
は無視できるほど少なくなる。従って、はとんど酸素イ
オン（Ｏｌ−）のみの電荷の移動により電流が流れ、印
加電圧を高くすると第２図に示す如く上記の出力電流は
増大し、電極の三相界面への水分の拡散量が限界に達す
ると出力電流は飽和するに至る。この飽和した電流を限
界電流と呼ぶが、この限界電流値ｒＬは第３図に示す如
く絶対湿度と比例関係にある。従って、この関係をあら
かじめ求めておけば測定した限界電流値から絶対湿度を
知ることができる。Cathode HzO+2e--'82 +O"-+1
) Anode H20→18Q2+'lH”
f21 However, since the decomposition of HtO at the anode is suppressed by the micropores 4 of the cap 5 as a gas diffusion control layer, hydrogen ions (H゛) are more concentrated than oxygen ions (O2-).
becomes negligible. Therefore, current flows mostly due to the movement of charges of oxygen ions (Ol-), and when the applied voltage is increased, the above output current increases as shown in Figure 2, and moisture flows to the three-phase interface of the electrode. When the amount of diffusion reaches its limit, the output current reaches saturation. This saturated current is called a limiting current, and this limiting current value rL has a proportional relationship with absolute humidity as shown in FIG. Therefore, if this relationship is determined in advance, the absolute humidity can be determined from the measured limiting current value.
前述の如く酸素が存在しない雰囲気中では印加電圧が第
２図における■。以下では水が電気分解しないので出力
電流が観察されず、従って、■。As mentioned above, in an atmosphere without oxygen, the applied voltage is indicated by ■ in FIG. Below, no output current is observed because the water does not electrolyze, and therefore ■.
以上の電圧を印加して測定する。なお、理論的にはＶ、
＃１．Ｉ Ｖであることが知られている。Measure by applying the above voltage. In addition, theoretically V,
#1. It is known that IV.
酸素を含む雰囲気中では酸素が酸素イオンとなる電圧と
、水が分解して酸素イオンが発生する電圧は異なるので
、第４図の如く二段の平坦部をもつ電流特性となる。酸
素が存在するとカソード側では次の反応が起こる。In an atmosphere containing oxygen, the voltage at which oxygen becomes oxygen ions and the voltage at which water decomposes and generates oxygen ions are different, resulting in a current characteristic with two flat parts as shown in FIG. In the presence of oxygen, the following reaction occurs on the cathode side.
カソード ’／ｚ Ｏｘ ＋２ｅ−−’ Ｏ”−（
３１第４図において（１）の領域は上記の反応（３）に
より酸素イオンが発生する領域であり、（ＩＩ）の領域
はこの反応（３）に水が分解して酸素イオンが発生する
前記の反応口）が加わる領域である。従って、この場合
は印加電圧を切り替えることによって二段の飽和電流を
測定してその差へ■、を限界電流値として求め、第３図
の関係から絶対湿度を知ることができる。従って、前記
の酸素を含まない雰囲気中の湿度の測定は、上記の酸素
を含む雰囲気中での測定における酸素が０である場合と
して測定すればよい。Cathode '/z Ox +2e--' O”-(
31 In Figure 4, the region (1) is the region where oxygen ions are generated by the above reaction (3), and the region (II) is the region where water decomposes during this reaction (3) and oxygen ions are generated. This is the area where the reaction port) is added. Therefore, in this case, the two-stage saturation current is measured by switching the applied voltage, and the difference between them is determined as the limiting current value, and the absolute humidity can be determined from the relationship shown in FIG. Therefore, the humidity in the oxygen-free atmosphere may be measured on the assumption that the oxygen content in the oxygen-containing atmosphere is 0.
ところで、本実施例では、アノード面への気体拡散制限
手段として、微小孔が形成されたキャップをカソード上
に被冠させているが、気体拡散を制御する手段としては
種々の実施例を用いることが可能である。例えば、多孔
質セラミックなどでカソード全面あるいは一部を覆って
もよいし、アノード上に薄板を若干の間隙をもたせて載
置し、その間隙の気体拡散制御作用を利用したものなど
、アノード面への気体拡散を制限する手段をすべて含む
ものである。Incidentally, in this embodiment, a cap in which micropores are formed is placed over the cathode as means for restricting gas diffusion to the anode surface, but various embodiments may be used as means for controlling gas diffusion. is possible. For example, the whole or part of the cathode may be covered with porous ceramic, or a thin plate may be placed on the anode with a slight gap, and the gas diffusion control effect of the gap may be used to cover the anode surface. This includes all means for limiting gas diffusion.
（発明の効果）
ペロプスカイト型酸化物よりなる固体電解質はほとんど
大部分のものが水素イオンと酸素イオン両方の伝導性を
有するものが多く、本発明においてはこのような固体電
解質を用いるので材料の選択が容易で、また、従来の赤
外線吸収スペクトルを利用する方法ではｐｐｍ領域の絶
対湿度しか精度よく測定できなかったが、本発明では数
％以下の絶対湿度を精度よく測定することができる。(Effects of the Invention) Most solid electrolytes made of perovskite oxides have conductivity for both hydrogen ions and oxygen ions, and since such solid electrolytes are used in the present invention, the material It is easy to select, and while conventional methods using infrared absorption spectra could only accurately measure absolute humidity in the ppm range, the present invention can accurately measure absolute humidity of several percent or less.
第１図は本発明による湿度測定に用いる湿度センサ素子
の断面図、第２図は本発明に係る湿度センサの印加電圧
と出力電流との関係を示すグラフ、第３図は同じく限界
電流値と絶対湿度との関係を示すグラフ、第４図は同し
く酸素を含む雰囲気中での印加電圧と出力電流との関係
を示すグラフである。
１：固体電解質、２ニアノード、３：カソード、４：微
小孔、５：気体拡散制御層としてのキャップ。
代理人 弁理士 竹 内 ９
第１図
第 ２図
Ｅ’Ｆカロ勾１万ＥFIG. 1 is a cross-sectional view of a humidity sensor element used for humidity measurement according to the present invention, FIG. 2 is a graph showing the relationship between applied voltage and output current of the humidity sensor according to the present invention, and FIG. 3 is a graph showing the relationship between the limiting current value and the output current. A graph showing the relationship with absolute humidity, and FIG. 4 is a graph showing the relationship between applied voltage and output current in an oxygen-containing atmosphere. 1: solid electrolyte, 2 near node, 3: cathode, 4: micropore, 5: cap as gas diffusion control layer. Agent Patent Attorney Takeuchi 9 Figure 1 Figure 2 E'F Calorie 10,000 E
Claims (2)
持った固体電解質の両面に多孔性電極を設け、その一方
をアノード、他方をカソードとし、アノードを蔽う気体
拡散制御層を設けて、両電極間に直流電圧を印加し、雰
囲気中に含まれる水分がカソード上で電気分解すること
により生ずる酸素イオン（Ｏ＾２＾−）をキャリヤとす
る出力電流により湿度を検出することを特徴とする固体
電解質を用いた湿度測定方法。(1) Porous electrodes are provided on both sides of a solid electrolyte that has both hydrogen ion conductivity and oxygen ion conductivity, one of which is used as an anode and the other as a cathode, and a gas diffusion control layer that covers the anode is provided. Humidity is detected by applying a DC voltage between the electrodes and detecting the output current using oxygen ions (O^2^-) as carriers, which are generated by electrolyzing moisture contained in the atmosphere on the cathode. Humidity measurement method using solid electrolyte.
持った固体電解質がＢａＣｅＯ＿３の如きペロブスカイ
ト型酸化物である特許請求の範囲第１項記載の固体電解
質を用いた湿度測定方法。(2) A humidity measuring method using a solid electrolyte according to claim 1, wherein the solid electrolyte having both hydrogen ion conductivity and oxygen ion conductivity is a perovskite oxide such as BaCeO_3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61227960A JPS6383661A (en) | 1986-09-29 | 1986-09-29 | Method for measuring humidity by using solid electrolyte |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61227960A JPS6383661A (en) | 1986-09-29 | 1986-09-29 | Method for measuring humidity by using solid electrolyte |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6383661A true JPS6383661A (en) | 1988-04-14 |
Family
ID=16868953
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61227960A Pending JPS6383661A (en) | 1986-09-29 | 1986-09-29 | Method for measuring humidity by using solid electrolyte |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6383661A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0677741A2 (en) * | 1994-04-12 | 1995-10-18 | Matsushita Electric Industrial Co., Ltd. | Oxygen sensor |
| EP1635171A2 (en) * | 1998-04-06 | 2006-03-15 | Matsushita Electrical Industrial Co., Ltd | Hydrocarbon sensor |
-
1986
- 1986-09-29 JP JP61227960A patent/JPS6383661A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0677741A2 (en) * | 1994-04-12 | 1995-10-18 | Matsushita Electric Industrial Co., Ltd. | Oxygen sensor |
| EP0677741A3 (en) * | 1994-04-12 | 1996-05-01 | Matsushita Electric Ind Co Ltd | Oxygen sensor. |
| EP1635171A2 (en) * | 1998-04-06 | 2006-03-15 | Matsushita Electrical Industrial Co., Ltd | Hydrocarbon sensor |
| EP1635171A3 (en) * | 1998-04-06 | 2009-09-09 | Panasonic Corporation | Hydrocarbon sensor |
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