JP2014016335A - Integrated reference electrode - Google Patents
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本発明は一体型参照電極に関し、特に軽水炉構造材料等の腐食電位（ＥＣＰ）測定の際に適用して有用なものである。 The present invention relates to an integrated reference electrode, and is particularly useful when applied to the measurement of corrosion potential (ECP) of light water reactor structural materials and the like.
軽水炉構造材料の腐食電位（ＥＣＰ）測定は炉内環境モニタリングに最も適した技術である。炉内ＥＣＰ測定には長期間安定に動作する参照電極が必要であるが、放射線照射下で簡便に利用できる電極は存在しない。そこで、この種の用途に、セラミックス管を酸素伝導体として用いる金属／酸化物電極が提案されている。かかる金属／酸化物電極は、化学的に安定で、酸化還元系から影響を受けない。そのため炉内用参照電極として金属／酸化物電極の適用が期待できる（例えば、非特許文献１および非特許文献２参照）。 Corrosion potential (ECP) measurement of light water reactor structural materials is the most suitable technique for in-reactor environmental monitoring. In-furnace ECP measurement requires a reference electrode that operates stably for a long period of time, but there is no electrode that can be easily used under irradiation. Therefore, a metal / oxide electrode using a ceramic tube as an oxygen conductor has been proposed for this type of application. Such metal / oxide electrodes are chemically stable and unaffected by the redox system. Therefore, application of a metal / oxide electrode as a reference electrode for a furnace can be expected (for example, see Non-Patent Document 1 and Non-Patent Document 2).
図１１は、従来技術に係る、この種の金属／酸化物電極で構成した参照電極を概念的に示す説明図である。同図に示すように、参照電極IIIは、セラミックス管０１中に、金属／金属酸化物の混合物で形成するＭ／Ｏ電極０２を固体電解質として封入したものである。ここで、セラミックス管０１は、例えばイットリア安定化ジルコニア（ＹＳＺ）で形成され、Ｍ／Ｏ電極０２は、例えばＮｉ／ＮｉＯで形成される。また、セラミックス管０１はその上端部で構造材としての金属ケース０３にロウ付けにより固着された状態で、例えば原子炉内等の所定の計測部位に設置される。Ｍ／Ｏ電極０２には導線０４の先端を当接させてあり、Ｍ／Ｏ電極０２の電位を外部で計測し得るように構成してある。 FIG. 11 is an explanatory diagram conceptually showing a reference electrode composed of this type of metal / oxide electrode according to the prior art. As shown in the figure, the reference electrode III is a ceramic tube 01 in which an M / O electrode 02 formed of a metal / metal oxide mixture is sealed as a solid electrolyte. Here, the ceramic tube 01 is made of, for example, yttria stabilized zirconia (YSZ), and the M / O electrode 02 is made of, for example, Ni / NiO. The ceramic tube 01 is installed at a predetermined measurement site such as in a nuclear reactor, for example, with its upper end fixed to a metal case 03 as a structural material by brazing. The tip of the conducting wire 04 is brought into contact with the M / O electrode 02 so that the potential of the M / O electrode 02 can be measured externally.
上述の如き参照電極IIIは、放射線照射下ではＭ／Ｏ電極０２を封入しているセラミックス管０１と金属ケース０３との接合部０５で腐食が生じ、この部分が破損する場合がある。破損した場合には、環境の溶液がセラミックス管０１内に流入し、またはセラミックス管０１からＭ／Ｏ電極０２を形成する粉末状の金属／金属酸化物が環境の溶液内に流出して、これを汚損する虞がある。 The reference electrode III as described above may be corroded at the joint portion 05 between the ceramic tube 01 enclosing the M / O electrode 02 and the metal case 03 under radiation irradiation, and this portion may be damaged. In the case of breakage, the environmental solution flows into the ceramic tube 01, or the powdered metal / metal oxide forming the M / O electrode 02 flows out of the ceramic tube 01 into the environmental solution. There is a risk of fouling.
さらに、セラミックス管０１は溶液中でのインピーダンスが低温（室温程度）で非常に高い。このためＭ／Ｏ電極０２は専ら高温（９０℃以上）で動作させるものとして使用していた。この結果、例えば軽水炉の起動停止等の低温時のＥＣＰ測定には利用することができない。 Furthermore, the ceramic tube 01 has a very high impedance in solution at a low temperature (about room temperature). For this reason, the M / O electrode 02 has been used exclusively for operation at a high temperature (90 ° C. or higher). As a result, it cannot be used for ECP measurement at low temperatures, such as starting and stopping a light water reactor.
また、セラミックス管０１は機械的および熱的な衝撃に弱く、セラミックス管０１の破損に伴う高温蒸気の外部への漏えいやＭ／Ｏ電極０２に用いる固体電解質の環境中への漏洩が懸念される。 Further, the ceramic tube 01 is vulnerable to mechanical and thermal shocks, and there is a concern about leakage of high-temperature steam to the outside due to breakage of the ceramic tube 01 and leakage of the solid electrolyte used for the M / O electrode 02 into the environment. .
本発明は、上記従来技術に鑑み、環境温度の低温域から高温域の広い温度領域において安定した電位を示し、また機械的にも頑強な一体型参照電極を提供することを目的とする。 An object of the present invention is to provide an integrated reference electrode that exhibits a stable potential in a wide temperature range from a low temperature range to a high temperature range and is mechanically robust in view of the above-described prior art.
上記目的を達成する本発明は、次の知見を基礎とするものである。すなわち、上述の如き従来技術に係る参照電極IIIの問題を解決する参照電極として、セラミックスと酸化物を金属基板上に成膜した一体型参照電極が考えられる。かかる一体型参照電極を形成することができれば、高い動作温度（例えば１５０℃以上）で使用することができると同時に、セラミックスの薄膜化によりインピーダンスを下げることが可能であるため、低い温度領域でも使用し得ると考えられる。 The present invention that achieves the above object is based on the following knowledge. That is, as a reference electrode that solves the problem of the reference electrode III according to the prior art as described above, an integrated reference electrode in which a ceramic and an oxide film are formed on a metal substrate can be considered. If such an integrated reference electrode can be formed, it can be used at a high operating temperature (for example, 150 ° C. or higher), and at the same time, the impedance can be lowered by reducing the thickness of the ceramic. It is considered possible.
ただ、Ｍ／Ｏ電極０２を薄膜化した場合、Ｍ／Ｏ電極０２を構成する金属と金属酸化物との比率を制御することが困難であるため、両者の比率がどのようなものになるか予想が付かない。従来、金属と金属酸化物との比率は１対１またはその近傍であることが望ましいとされ、実際、従来のＭ／Ｏ電極０２における金属と金属酸化物の比率は１対１またはその近傍となるように形成されていた。 However, when the thickness of the M / O electrode 02 is reduced, it is difficult to control the ratio of the metal and the metal oxide constituting the M / O electrode 02. I can't predict. Conventionally, it is desirable that the ratio of metal to metal oxide is 1: 1 or the vicinity thereof. In fact, the ratio of metal to metal oxide in the conventional M / O electrode 02 is 1: 1 or the vicinity thereof. It was formed to become.
そこで、本発明者等は、金属と金属酸化物の薄膜化の可能性を検証すべく、図１１に示す構造の参照電極IIIにおいて、Ｍ／Ｏ電極０２を構成する金属と金属酸化物の比率を種々変化させて、比率を変化させた場合の電極電位の特性を調べた。具体的には、最適な固体電解質の組成として選定したＮｉ／ＮｉＯ比とＭ／Ｏ電極０２の電極電位との関係を調べた。 Therefore, the present inventors have examined the possibility of thinning the metal and metal oxide, and in the reference electrode III having the structure shown in FIG. 11, the ratio of the metal and metal oxide constituting the M / O electrode 02 is as follows. The characteristics of the electrode potential when the ratio was changed with various changes were investigated. Specifically, the relationship between the Ni / NiO ratio selected as the optimal solid electrolyte composition and the electrode potential of the M / O electrode 02 was examined.
その結果を図１２に示す。ここで、実験値は環境の環境温度が２８８℃に到達後、電極電位が安定したときの計測値を統計的に処理した値である。併せてＮｉ／ＮｉＯの平衡反応から求めた理論値を破線で示す。 The result is shown in FIG. Here, the experimental value is a value obtained by statistically processing the measured value when the electrode potential is stabilized after the environmental temperature of the environment reaches 288 ° C. In addition, the theoretical value obtained from the equilibrium reaction of Ni / NiO is indicated by a broken line.
図１２を参照すれば、Ｍ／Ｏ電極０２の電極電位はＮｉ／ＮｉＯ比に対して顕著な影響がなく、許容できる範囲に収まることが確認できる。Ｎｉが過剰な場合、電極電位はほぼ一定である。一方、ＮｉＯの割合が増加するにつれ電極電位が貴側にシフトするが、高温水中での電位測定のばらつきと比較すると十分に許容できる。かかる結果は短期間の試験を繰り返した結果である。そのため、長期間の試験では固体電解質の継時変化で酸化物の割合が増加し、図１２とは傾向が異なる可能性が考えられるが、Ｎｉ／ＮｉＯ比が１：１０と１０：１と極端に変化した場合のＭ／Ｏ電極０２の電極電位の差は高温での電位計測のばらつきと比較して小さく、固体電解質の継時変化による影響は少ないと推測される。 Referring to FIG. 12, it can be confirmed that the electrode potential of the M / O electrode 02 has no significant influence on the Ni / NiO ratio and falls within an allowable range. When Ni is excessive, the electrode potential is almost constant. On the other hand, as the proportion of NiO increases, the electrode potential shifts to the noble side, but it is well tolerated as compared with the variation in potential measurement in high temperature water. Such a result is a result of repeated short-term tests. Therefore, in the long-term test, the ratio of the oxide increases due to the change of the solid electrolyte over time, and it is possible that the tendency is different from that in FIG. 12, but the Ni / NiO ratio is extremely extreme at 1:10 and 10: 1. The difference in the electrode potential of the M / O electrode 02 when it is changed to is smaller than the variation in potential measurement at a high temperature, and it is estimated that the influence of the change in the solid electrolyte over time is small.
この結果より、高温水中でＮｉ／ＮｉＯ電極は理論値に近い値を示し、Ｎｉ／ＮｉＯ比による電極電位への影響が少ないことから、Ｎｉ／ＮｉＯを薄膜化しても電極電位は十分許容範囲に収まると考えられる。 From this result, the Ni / NiO electrode shows a value close to the theoretical value in high-temperature water, and the influence of the Ni / NiO ratio on the electrode potential is small. It is thought that it will fit.
かかる知見を基礎とする本願発明の第１の態様は、
金属基板上に金属酸化物膜を形成し、さらに前記金属酸化物膜の表面を覆うように前記金属酸化物膜上にセラミックス膜を形成したことを特徴とする一体型参照電極にある。
The first aspect of the present invention based on such knowledge is as follows:
In the integrated reference electrode, a metal oxide film is formed on a metal substrate, and a ceramic film is formed on the metal oxide film so as to cover the surface of the metal oxide film.
本態様によれば、セラミックス膜部分のインピーダンスを飛躍的に低減し得るので測定環境が低温であっても参照電極としての所定の機能を発揮させることができる。また、機械的強度の脆弱部である他の部材との接合部がないので、機械的な寿命を向上させることができ、長期に亘る所定の安定な機能を保証することができる。 According to this aspect, since the impedance of the ceramic film portion can be drastically reduced, a predetermined function as the reference electrode can be exhibited even if the measurement environment is low temperature. Moreover, since there is no joint part with the other member which is a weak part of mechanical strength, a mechanical lifetime can be improved and the predetermined stable function over a long period can be ensured.
本発明の第２の態様は、
金属基板の表面を熱酸化させて前記金属基板上に金属酸化物膜を形成し、さらに前記金属酸化物膜の表面を覆うように前記金属酸化物膜上にセラミックス膜を形成したことを特徴とする一体型参照電極にある。
The second aspect of the present invention is:
The surface of the metal substrate is thermally oxidized to form a metal oxide film on the metal substrate, and a ceramic film is formed on the metal oxide film so as to cover the surface of the metal oxide film. The integrated reference electrode.
本態様によれば、第１の態様に記載する一体型参照電極と同様の作用・効果に加え、さらに金属基板の熱酸化による酸化膜で所定の金属酸化物膜を形成しているので、金属基板と金属酸化物膜との界面における剥離を防止することができ、長期に亘り安定した電極電位特性を得ることができる。 According to this aspect, in addition to the same operation and effect as the integrated reference electrode described in the first aspect, the predetermined metal oxide film is formed by the oxide film formed by thermal oxidation of the metal substrate. Separation at the interface between the substrate and the metal oxide film can be prevented, and stable electrode potential characteristics can be obtained over a long period of time.
本発明の第３の態様は、
第２の態様に記載する一体型参照電極において、
前記熱酸化による酸化膜は、前記金属基板を、５００℃以上に加熱して形成したことを特徴とする一体型参照電極にある。
The third aspect of the present invention is:
In the integrated reference electrode described in the second aspect,
The oxide film formed by thermal oxidation is an integrated reference electrode formed by heating the metal substrate to 500 ° C. or higher.
本発明の第４の態様は、
第３の態様に記載する一体型参照電極において、
前記熱酸化による酸化膜は、前記金属基板を、６００℃以上に加熱して形成することを特徴とする一体型参照電極にある。
The fourth aspect of the present invention is:
In the integrated reference electrode described in the third aspect,
The oxide film formed by thermal oxidation is an integrated reference electrode formed by heating the metal substrate to 600 ° C. or higher.
本発明の第５の態様は、
請求項１〜請求項４の何れか一つに記載する一体型参照電極において、
前記セラミックス膜で覆われた前記金属酸化物膜の感応部を除く前記金属酸化物膜および金属基板を覆合部材で覆うことにより一体化したことを特徴とする一体型参照電極にある。
According to a fifth aspect of the present invention,
In the integrated reference electrode according to any one of claims 1 to 4,
In the integrated reference electrode, the metal oxide film and the metal substrate excluding the sensitive part of the metal oxide film covered with the ceramic film are integrated by covering with a covering member.
本態様によれば、当該一体型参照電極を一つの構造体として十分な機械的強度を備えたものとすることができる。 According to this aspect, the integrated reference electrode can be provided as a single structural body with sufficient mechanical strength.
本発明の第６の態様は、
第１〜第５の態様の何れか一つに記載する一体型参照電極において、
前記金属はＮｉ、前記金属酸化物膜はＮｉＯ、セラミックス膜はイットリア安定化ジルコニア（ＹＳＺ）を用いたことを特徴とする一体型参照電極にある。
The sixth aspect of the present invention is:
In the integrated reference electrode according to any one of the first to fifth aspects,
In the integrated reference electrode, the metal is Ni, the metal oxide film is NiO, and the ceramic film is yttria stabilized zirconia (YSZ).
本態様によれば、当該一体型参照電極を容易かつ適確に形成することができる。 According to this aspect, the integrated reference electrode can be formed easily and accurately.
本発明の第７の態様は、
第１〜第６の態様の何れか一つに記載する一体型参照電極において、
測定対象の環境のｐＨに対する電極電位の特性であるｐＨ特性が既知であることを特徴とする一体型参照電極にある。
The seventh aspect of the present invention is
In the integrated reference electrode according to any one of the first to sixth aspects,
The integrated reference electrode has a known pH characteristic that is a characteristic of an electrode potential with respect to a pH of an environment to be measured.
本態様によれば、別途環境のｐＨを計測しておくことで、容易に当該一体型参照電極の電位を適正な値に補正することができる。 According to this aspect, the potential of the integrated reference electrode can be easily corrected to an appropriate value by separately measuring the pH of the environment.
本発明によれば、セラミックス膜を用いることで簡単に薄膜化が可能となり、電極のインピーダンスを低下させることができる結果、室温での電極電位の測定が可能になる。さらに、セラミックス膜により環境の構成要素である溶液と固体電解質を隔離でき、溶液中の酸化還元雰囲気に対して電極電位が影響を受けず、一体型参照電極電位は溶液中のｐＨのみで決定される。これらのことより、本発明に係る一体型参照電極は溶液中のｐＨが既知の場合、参照電極として用いることができる。 According to the present invention, it is possible to easily reduce the thickness by using a ceramic film, and to reduce the impedance of the electrode. As a result, it is possible to measure the electrode potential at room temperature. In addition, the ceramic membrane can separate the solution, which is a component of the environment, from the solid electrolyte, the electrode potential is not affected by the redox atmosphere in the solution, and the integrated reference electrode potential is determined only by the pH in the solution. The Accordingly, the integrated reference electrode according to the present invention can be used as a reference electrode when the pH in the solution is known.
さらに、本発明に係る一体型参照電極は従来型金属／酸化物電極の主な破損原因となるセラミックス管およびその接合部が存在しない。この結果、固体電解質の溶液への漏洩を回避することができる。 Furthermore, the integrated reference electrode according to the present invention does not have a ceramic tube and its joint which are the main cause of damage of the conventional metal / oxide electrode. As a result, leakage of the solid electrolyte into the solution can be avoided.
以下、本発明の実施の形態を図面に基づき詳細に説明する。 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
＜第１の実施の形態＞
図１は本発明の実施の形態に係る一体型参照電極を概念的に示す説明図である。同図に示すように、本形態に係る一体型参照電極Ｉは、金属基板２Ａ上に金属酸化物膜２Ｂを形成し、さらに金属酸化物膜２Ｂの表面を覆うように金属酸化物膜２Ｂ上にセラミックス薄膜１を形成したものである。ここで、金属基板２Ａと金属酸化物膜２ＢとがＭ／Ｏ電極２を構成している。
<First Embodiment>
FIG. 1 is an explanatory diagram conceptually showing an integrated reference electrode according to an embodiment of the present invention. As shown in the figure, the integrated reference electrode I according to this embodiment forms a metal oxide film 2B on a metal substrate 2A, and further covers the surface of the metal oxide film 2B so as to cover the surface of the metal oxide film 2B. The ceramic thin film 1 is formed. Here, the metal substrate 2 </ b> A and the metal oxide film 2 </ b> B constitute the M / O electrode 2.
さらに、本形態に係る一体型参照電極Ｉは、セラミックス薄膜１で覆われた金属酸化物膜２Ｂの感応部を除く金属酸化物膜２Ｂおよび金属基板２Ａを覆う金属等の覆合部材３で一体化してある。このように一体化することは必須ではないが、かかる構成とすることにより、一体型参照電極Ｉを一つの構造体として十分な機械的強度を備えたものとすることができる。 Further, the integrated reference electrode I according to the present embodiment is integrated with a covering member 3 such as a metal covering the metal oxide film 2B and the metal substrate 2A excluding the sensitive part of the metal oxide film 2B covered with the ceramic thin film 1. It has become. Such integration is not essential, but by adopting such a configuration, the integrated reference electrode I can be provided as a single structural body with sufficient mechanical strength.
本形態においては、金属基板２ＡをＮｉ、金属酸化物膜をＮｉＯ、セラミックス薄膜をイットリア安定化ジルコニア（ＹＳＺ）でそれぞれ形成した。さらに具体的には、Ｎｉの金属基板２Ａ上に５００ｎｍのＮｉＯ薄膜からなる金属酸化物膜２Ｂと、１００ｎｍのＹＳＺ薄膜からなるセラミックス薄膜１を、例えばスパッタリングによる蒸着により形成した。 In this embodiment, the metal substrate 2A is formed of Ni, the metal oxide film is formed of NiO, and the ceramic thin film is formed of yttria stabilized zirconia (YSZ). More specifically, a metal oxide film 2B made of a 500 nm NiO thin film and a ceramic thin film 1 made of a 100 nm YSZ thin film were formed on a Ni metal substrate 2A by, for example, vapor deposition by sputtering.
かかる一体型参照電極Ｉにおいて、緩衝液中（室温、大気飽和）でのｐＨ応答を調べた。同図を参照すれば、一体型参照電極Ｉの電極電位はｐＨの増加に対して−５０．３ｍＶ／ｐＨの傾きで直線的に減少し、図１１に示す従来のＭ／Ｏ電極０２では動作しない室温でｐＨ電極としての動作が確認できた。 In the integrated reference electrode I, the pH response in a buffer solution (room temperature, atmospheric saturation) was examined. Referring to FIG. 11, the electrode potential of the integrated reference electrode I decreases linearly with a slope of −50.3 mV / pH with respect to the increase in pH, and the conventional M / O electrode 02 shown in FIG. The operation as a pH electrode was confirmed at room temperature.
本形態によれば、ＹＳＺの薄膜で形成したセラミックス薄膜１は１００ｎｍとごく薄いので、この部分のインピーダンスを飛躍的に低減し得る。この結果、測定環境が低温であっても参照電極としての所定の機能を発揮させることができる。 According to this embodiment, since the ceramic thin film 1 formed of a YSZ thin film is as thin as 100 nm, the impedance of this portion can be drastically reduced. As a result, a predetermined function as a reference electrode can be exhibited even when the measurement environment is low temperature.
また、Ｎｉの金属基板２Ａ上にＮｉＯの金属酸化物膜２Ｂを形成し、さらに金属酸化物膜２ＢをＹＳＺの薄膜で形成したセラミックス薄膜１で覆ったので、図１１に示す従来の参照電極IIIの如き、機械的強度の脆弱部である他の部材との接合部０５がない。この結果、機械的な寿命を向上させることができ、長期に亘る所定の安定な機能を保証することができる。 Since the NiO metal oxide film 2B is formed on the Ni metal substrate 2A, and the metal oxide film 2B is covered with the ceramic thin film 1 formed of a YSZ thin film, the conventional reference electrode III shown in FIG. Thus, there is no joint portion 05 with another member that is a weak portion of mechanical strength. As a result, the mechanical life can be improved, and a predetermined stable function can be ensured over a long period of time.
測定対象の環境のｐＨに対する電極電位の特性であるｐＨ特性が既知であるので、別途環境のｐＨを計測しておくことで、容易に当該一体型参照電極Ｉの電位を適正な値に補正することができる。 Since the pH characteristic that is the characteristic of the electrode potential with respect to the pH of the environment to be measured is known, the potential of the integrated reference electrode I can be easily corrected to an appropriate value by separately measuring the pH of the environment. be able to.
＜第２の実施の形態＞
図１に示す第１の実施の形態に係る一体型参照電極Ｉによれば、上述の如き作用・効果を発揮させることができる。ところが、所定の溶液に浸漬した通常の使用態様では、時間の経過とともに電極電位が著しく減少する。これは、時間の経過とともに金属酸化物膜２Ｂが金属基板２Ａから剥離するためであると考えられる。実際、電極電位が著しく減少した一体型参照電極Ｉを透過型電子顕微鏡（ＴＥＭ）により分析した結果、金属基板（Ｎｉ基板）２Ａと酸化物膜（ＮｉＯ薄膜）２Ｂの界面が剥離していることが判明した。
<Second Embodiment>
According to the integrated reference electrode I according to the first embodiment shown in FIG. 1, the above-described actions and effects can be exhibited. However, in a normal usage mode immersed in a predetermined solution, the electrode potential is remarkably reduced with time. This is considered to be because the metal oxide film 2B peels off from the metal substrate 2A with time. In fact, as a result of analyzing the integrated reference electrode I with a significantly reduced electrode potential using a transmission electron microscope (TEM), the interface between the metal substrate (Ni substrate) 2A and the oxide film (NiO thin film) 2B is peeled off. There was found.
この結果、第１の実施の形態に係る一体型参照電極Ｉは、所定の機能を発揮する一体型参照電極としての寿命が短いという問題を有している。 As a result, the integrated reference electrode I according to the first embodiment has a problem that the lifetime as an integrated reference electrode that exhibits a predetermined function is short.
本形態は、かかる問題を解消し得るように第１の実施の形態をさらに改良したものである。 In the present embodiment, the first embodiment is further improved so that such a problem can be solved.
図３は本発明の第２の実施の形態に係る一体型参照電極を概念的に示す説明図である。なお、図３中、図１と同一部分には同一番号を付し、重複する説明は省略する。 FIG. 3 is an explanatory view conceptually showing an integrated reference electrode according to the second embodiment of the present invention. In FIG. 3, the same parts as those in FIG.
図３に示すように、本形態に係る一体型参照電極IIは、金属基板１２Ａの表面を熱酸化させて金属基板１２Ａ上に金属酸化物膜１２Ｃを形成するとともに、さらに金属酸化物膜１２Ｃの表面を覆うようにセラミックス薄膜１を形成したものである。したがって、本形態においては金属基板１２Ａおよび金属酸化物膜１２ＣでＭ／Ｏ電極１２を構成している。 As shown in FIG. 3, the integrated reference electrode II according to this embodiment forms a metal oxide film 12C on the metal substrate 12A by thermally oxidizing the surface of the metal substrate 12A. The ceramic thin film 1 is formed so as to cover the surface. Therefore, in this embodiment, the M / O electrode 12 is constituted by the metal substrate 12A and the metal oxide film 12C.
さらに具体的には、本形態においては、Ｎｉの金属基板１２Ａを加熱手段である、例えばマッフル炉に収納して所定の高温で所定時間加熱することにより金属基板１２Ａの表面を熱酸化させて、例えば５００ｎｍ程度の金属酸化物膜１２Ｃを形成する。その後、金属酸化物膜１２Ｃの表面に、例えば１００ｎｍ程度のＹＳＺ薄膜からなるセラミックス薄膜１を、例えばスパッタリングによる蒸着により形成する。このときの加熱温度は５００℃以上、好ましくは６００℃以上とする。 More specifically, in this embodiment, the surface of the metal substrate 12A is thermally oxidized by storing the Ni metal substrate 12A in a muffle furnace as a heating means, for example, and heating it at a predetermined high temperature for a predetermined time, For example, a metal oxide film 12C having a thickness of about 500 nm is formed. Thereafter, the ceramic thin film 1 made of a YSZ thin film of about 100 nm, for example, is formed on the surface of the metal oxide film 12C, for example, by vapor deposition by sputtering. The heating temperature at this time is 500 ° C. or higher, preferably 600 ° C. or higher.
図４は、本形態に係る一体型参照電極IIを所定の溶液（例えば、ｐＨ６．８９の中性リン酸標準液）に浸漬した場合の浸漬時間と電極電圧との関係を、第１の実施の形態に係る一体型参照電極Ｉとの比較において示す特性図である。同図において、Ａは本形態に係る一体型参照電極IIの特性、Ｂは第１の実施の形態に係る一体型参照電極Ｉの特性、Ｃは溶液の温度特性をそれぞれ示している。同図を参照すれば、本形態に係る一体型参照電極IIの場合、浸漬時間が経過してもほぼ一定の電極電位を維持しているのに対し、第１の実施の形態に係る一体型参照電極Ｉは浸漬時間の経過とともに急激に電極電位が低下している。すなわち、本形態に係る一体型参照電極IIの電位の変動は、第１の実施の形態に係る一体型参照電極Ｉに比較してドリフトが１／１０〜１／１００程度に収まる。このとき、溶液温度は２５℃程度で一定である。 FIG. 4 shows the relationship between the immersion time and the electrode voltage when the integrated reference electrode II according to this embodiment is immersed in a predetermined solution (for example, neutral phosphate standard solution of pH 6.89). It is a characteristic view shown in comparison with the integrated reference electrode I which concerns on a form of. In the figure, A indicates the characteristics of the integrated reference electrode II according to the present embodiment, B indicates the characteristics of the integrated reference electrode I according to the first embodiment, and C indicates the temperature characteristics of the solution. Referring to the figure, in the case of the integrated reference electrode II according to the present embodiment, the substantially constant electrode potential is maintained even after the immersion time has elapsed, whereas the integrated reference electrode II according to the first embodiment is maintained. In the reference electrode I, the electrode potential rapidly decreases as the immersion time elapses. That is, the fluctuation of the potential of the integrated reference electrode II according to the present embodiment has a drift of about 1/10 to 1/100 compared with the integrated reference electrode I according to the first embodiment. At this time, the solution temperature is constant at about 25 ° C.
図５は、第２の実施の形態に係る一体型参照電極IIを所定の溶液に浸漬した場合の前記溶液のｐＨと電極電圧の関係を、室温をパラメータとして示す特性図である。同図を参照すれば、第１の実施の形態に係る一体型参照電極Ｉと同様にｐＨの変化に対して電極電位が変化することが分かる。この場合の傾きは、理論値と比較して５％程度小さい。ちなみに、第１の実施の形態に係る一体型参照電極Ｉは１５％である。 FIG. 5 is a characteristic diagram showing the relationship between the pH of the solution and the electrode voltage when the integrated reference electrode II according to the second embodiment is immersed in a predetermined solution, using room temperature as a parameter. Referring to the figure, it can be seen that the electrode potential changes with respect to the change in pH, as in the integrated reference electrode I according to the first embodiment. The slope in this case is about 5% smaller than the theoretical value. Incidentally, the integrated reference electrode I according to the first embodiment is 15%.
上述の如き一体型参照電極IIにおいて適正な加熱温度、すなわち良好な金属酸化物膜１２Ｃが形成される加熱温度を調べた。さらに詳言すると、Ｎｉの金属基板１２Ａをマッフル炉で１時間程度加熱して得られた金属基板１２Ａ上に５００ｎｍのＮｉＯ薄膜からなる金属酸化物膜１２Ｃが形成された試料のラマンスペクトル強度を調べた。その結果を図６に示す。 In the integrated reference electrode II as described above, an appropriate heating temperature, that is, a heating temperature at which a good metal oxide film 12C is formed was examined. More specifically, the Raman spectral intensity of a sample in which a metal oxide film 12C made of a NiO thin film of 500 nm is formed on a metal substrate 12A obtained by heating the Ni metal substrate 12A in a muffle furnace for about 1 hour is examined. It was. The result is shown in FIG.
図６は、加熱温度（４００℃、４５０℃、５００℃、５５０℃、６００℃、８００℃）をパラメータとして熱酸化させた各試料のラマンシフトに対するラマンスペクトルの強度を示す特性図、図７は各試料の外観を示す写真である。 FIG. 6 is a characteristic diagram showing the intensity of the Raman spectrum with respect to the Raman shift of each sample thermally oxidized using the heating temperature (400 ° C., 450 ° C., 500 ° C., 550 ° C., 600 ° C., 800 ° C.) as a parameter. It is a photograph which shows the external appearance of each sample.
金属酸化物膜１２Ｃが形成されると、図６中に点線で示すラマンシフトの位置には、ラマンスペクトル強度のピークが形成される。図６を参照すれば、加熱温度が５００℃以上の場合に、ＮｉＯに対応するラマンシフトの位置で、良好な金属酸化物膜１２Ｃが形成されていることを示すピークが認められる。 When the metal oxide film 12C is formed, a peak of Raman spectrum intensity is formed at the position of the Raman shift indicated by a dotted line in FIG. Referring to FIG. 6, when the heating temperature is 500 ° C. or higher, a peak indicating that a good metal oxide film 12C is formed at the Raman shift position corresponding to NiO is recognized.
これは、図７に示す試料の外観を表す写真でも確認することができる。すなわち、図７の上列の最も左側に示す加熱前の試料は、Ｎｉの色である銀色であるが、加熱による酸化が進むにつれ赤褐色（４００℃）、青味がかった赤褐色（４５０℃）、薄い緑（５００℃、５５０℃）および濃い緑（６００℃、８００℃）と変化している。試料の色は緑が濃くなるにつれ良好な金属酸化物膜１２Ｃが形成されていることを表す。 This can also be confirmed by a photograph showing the appearance of the sample shown in FIG. That is, the sample before heating shown on the leftmost side of the upper row of FIG. 7 is silver which is the color of Ni, but reddish brown (400 ° C.), bluish reddish brown (450 ° C.) as oxidation by heating proceeds, It has changed from light green (500 ° C., 550 ° C.) and dark green (600 ° C., 800 ° C.). The color of the sample indicates that a good metal oxide film 12C is formed as green becomes darker.
図８および図９は、図７に示す各試料の断面のＴＥＭ像を示す写真で、図８（ａ）が４００℃で熱酸化させた場合、同図（ｂ）が４５０℃で熱酸化させた場合、図９（ａ）が５００℃で熱酸化させた場合、同図（ｂ）が５５０℃で熱酸化させた場合、同図（ｃ）が６００℃で熱酸化させた場合、同図（ｄ）が８００℃で熱酸化させた場合をそれぞれ示している。 8 and 9 are photographs showing TEM images of cross sections of the samples shown in FIG. 7. When FIG. 8 (a) is thermally oxidized at 400 ° C., FIG. 8 (b) is thermally oxidized at 450 ° C. 9 (a) is thermally oxidized at 500 ° C., FIG. 9 (b) is thermally oxidized at 550 ° C., and FIG. 9 (c) is thermally oxidized at 600 ° C. (D) shows the case where it is thermally oxidized at 800 ° C., respectively.
これらの図を参照すれば、４００℃および４５０℃で加熱した図８（ａ）および同図（ｂ）では２０〜３０ｎｍの薄い金属酸化物膜（ＮｉＯ膜）１２Ｃしか形成されず、酸化が不十分な部位が認められる。ちなみに、金属酸化物膜（ＮｉＯ膜）１２Ｃがぼやけた画像となり、金属基板１２Ａとの界面が明瞭な金属酸化物膜１２Ｃとはなっていない。 Referring to these figures, in FIGS. 8A and 8B heated at 400 ° C. and 450 ° C., only a thin metal oxide film (NiO film) 12C having a thickness of 20 to 30 nm is formed, and oxidation is not caused. Sufficient sites are observed. Incidentally, the metal oxide film (NiO film) 12C becomes a blurred image, and the interface with the metal substrate 12A is not a clear metal oxide film 12C.
一方、図９（ａ）〜図９（ｄ）においては、比較的厚い（１００ｎｍ以上）の安定した金属酸化物膜１２Ｃが認められた。そして、金属酸化物膜１２Ｃは温度が高くなるほど厚い良好な酸化膜となっている。 On the other hand, in FIGS. 9A to 9D, a relatively thick (100 nm or more) stable metal oxide film 12C was observed. The metal oxide film 12C is a good oxide film that is thicker as the temperature is higher.
これらの実験結果より、本形態における金属酸化物膜１２Ｃの形成に際しては、５００℃以上、好ましくは６００℃以上で加熱すれば良いことが分かる。 From these experimental results, it can be seen that the metal oxide film 12C in this embodiment may be heated at 500 ° C. or higher, preferably 600 ° C. or higher.
図１０は、第１の実施の形態に係る一体型参照電極Ｉと同様に、Ｎｉの金属基板２Ａの表面にＮｉＯの金属酸化物膜２Ｂを形成した試料を室温、空気飽和のもとで、ｐＨ６．８９中性リン酸標準液に５０時間程度浸漬した後におけるその断面のＴＥＭ像を示す写真である。同図に示す状態では、金属酸化物膜（ＮｉＯ薄膜）２Ｂが金属基板（Ｎｉ基板）２Ａから剥離していることが分かる。 FIG. 10 shows a sample in which a NiO metal oxide film 2B is formed on the surface of a Ni metal substrate 2A in the same manner as the integrated reference electrode I according to the first embodiment. It is a photograph which shows the TEM image of the cross section after being immersed in pH 6.89 neutral phosphoric acid standard solution for about 50 hours. In the state shown in the figure, it can be seen that the metal oxide film (NiO thin film) 2B is peeled off from the metal substrate (Ni substrate) 2A.
なお、上述の如く上記第１および第２の実施の形態では、一体型参照電極Ｉ、IIの固体電解質としてＮｉ／ＮｉＯを用いたが、他にもＣｕ／Ｃｕ２Ｏ、Ｆｅ／Ｆｅ３Ｏ４等が考えられる。 As described above, in the first and second embodiments, Ni / NiO is used as the solid electrolyte of the integrated reference electrodes I and II, but Cu / Cu 2 O and Fe / Fe 3 O are also used. 4 mag is considered.
本発明は密閉された原子炉構造物の健全性を検出する必要がある原子力産業等の産業分野において有効に利用することができる。 The present invention can be effectively used in industrial fields such as the nuclear power industry where it is necessary to detect the soundness of sealed reactor structures.
Ｉ、II 一体型参照電極
１ セラミックス薄膜
２ Ｍ／Ｏ電極
２Ａ 金属基板
２Ｂ 金属酸化物膜
３ 覆合部材
４ 導線
１２ Ｍ／Ｏ電極
１２Ａ 金属基板
１２Ｃ 金属酸化物膜
I, II Integrated reference electrode 1 Ceramic thin film 2 M / O electrode 2A Metal substrate 2B Metal oxide film 3 Cover member 4 Conductor 12 M / O electrode 12A Metal substrate 12C Metal oxide film
Claims (7)
前記熱酸化による酸化膜は、前記金属基板を、５００℃以上に加熱して形成したことを特徴とする一体型参照電極。 The integrated reference electrode according to claim 2,
The integrated reference electrode according to claim 1, wherein the oxide film formed by thermal oxidation is formed by heating the metal substrate to 500 ° C or higher.
前記熱酸化による酸化膜は、前記金属基板を、６００℃以上に加熱して形成することを特徴とする一体型参照電極。 The integrated reference electrode according to claim 3,
The integrated reference electrode according to claim 1, wherein the oxide film formed by thermal oxidation is formed by heating the metal substrate to 600 ° C or higher.
前記セラミックス膜で覆われた前記金属酸化物膜の感応部を除く前記金属酸化物膜および金属基板を覆合部材で覆うことにより一体化したことを特徴とする一体型参照電極。 In the integrated reference electrode according to any one of claims 1 to 4,
An integrated reference electrode, wherein the metal oxide film and the metal substrate excluding the sensitive part of the metal oxide film covered with the ceramic film are integrated by covering with a covering member.
前記金属はＮｉ、前記金属酸化物膜はＮｉＯ、セラミックス膜はイットリア安定化ジルコニア（ＹＳＺ）を用いたことを特徴とする一体型参照電極。 In the integrated reference electrode according to any one of claims 1 to 5,
An integrated reference electrode, wherein the metal is Ni, the metal oxide film is NiO, and the ceramic film is yttria stabilized zirconia (YSZ).
測定対象の環境のｐＨに対する電極電位の特性であるｐＨ特性が既知であることを特徴とする一体型参照電極。 In the integrated reference electrode according to any one of claims 1 to 6,
An integrated reference electrode having a known pH characteristic, which is a characteristic of an electrode potential with respect to a pH of an environment to be measured.
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5677751A (en) * | 1979-10-12 | 1981-06-26 | Gen Electric | Sensor for hydrogen ion |
| JPS59211854A (en) * | 1983-05-11 | 1984-11-30 | インタ−ナショナル ビジネス マシ−ンズ コ−ポレ−ション | Metallic oxide electrode |
| JPS63501379A (en) * | 1985-04-17 | 1988-05-26 | ベイヤ− ダイアグノステイク ウント エレクトロニクゲ−エムベ−ハ− | electrochemical sensor |
| JPH0445960U (en) * | 1990-08-22 | 1992-04-20 | ||
| JPH055717A (en) * | 1990-08-22 | 1993-01-14 | Toa Denpa Kogyo Kk | Ph-measuring electrode and its manufacture |
| JPH0599887A (en) * | 1991-10-09 | 1993-04-23 | Omron Corp | Amperometric electrode |
| JPH0868888A (en) * | 1994-05-23 | 1996-03-12 | General Electric Co <Ge> | Shroud electrochemical-potential monitor |
| WO1999040420A1 (en) * | 1998-02-04 | 1999-08-12 | Sanwa Newtec Co., Ltd. | Liquid sensor and body fluid leak sensing device comprising the same |
| JP2003004887A (en) * | 2001-06-21 | 2003-01-08 | Hitachi Ltd | CORROSION POTENTIAL SENSOR, BOILING WATER REACTOR POWER PLANT AND pH SENSOR |
| JP2004077482A (en) * | 2002-08-15 | 2004-03-11 | General Electric Co <Ge> | Ceramic electrochemical corrosion potential sensor probe with extended lifetime |
| JP2005140608A (en) * | 2003-11-06 | 2005-06-02 | Hitachi Ltd | Corrosion potential sensor |
| JP2006189344A (en) * | 2005-01-06 | 2006-07-20 | Denso Corp | Electrode pair for detecting acidity and basicity of oil, and deterioration detector for oil |
-
2012
- 2012-10-24 JP JP2012235088A patent/JP6004477B2/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5677751A (en) * | 1979-10-12 | 1981-06-26 | Gen Electric | Sensor for hydrogen ion |
| JPS59211854A (en) * | 1983-05-11 | 1984-11-30 | インタ−ナショナル ビジネス マシ−ンズ コ−ポレ−ション | Metallic oxide electrode |
| JPS63501379A (en) * | 1985-04-17 | 1988-05-26 | ベイヤ− ダイアグノステイク ウント エレクトロニクゲ−エムベ−ハ− | electrochemical sensor |
| JPH0445960U (en) * | 1990-08-22 | 1992-04-20 | ||
| JPH055717A (en) * | 1990-08-22 | 1993-01-14 | Toa Denpa Kogyo Kk | Ph-measuring electrode and its manufacture |
| JPH0599887A (en) * | 1991-10-09 | 1993-04-23 | Omron Corp | Amperometric electrode |
| JPH0868888A (en) * | 1994-05-23 | 1996-03-12 | General Electric Co <Ge> | Shroud electrochemical-potential monitor |
| WO1999040420A1 (en) * | 1998-02-04 | 1999-08-12 | Sanwa Newtec Co., Ltd. | Liquid sensor and body fluid leak sensing device comprising the same |
| JP2003004887A (en) * | 2001-06-21 | 2003-01-08 | Hitachi Ltd | CORROSION POTENTIAL SENSOR, BOILING WATER REACTOR POWER PLANT AND pH SENSOR |
| JP2004077482A (en) * | 2002-08-15 | 2004-03-11 | General Electric Co <Ge> | Ceramic electrochemical corrosion potential sensor probe with extended lifetime |
| JP2005140608A (en) * | 2003-11-06 | 2005-06-02 | Hitachi Ltd | Corrosion potential sensor |
| JP2006189344A (en) * | 2005-01-06 | 2006-07-20 | Denso Corp | Electrode pair for detecting acidity and basicity of oil, and deterioration detector for oil |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2016188838A (en) * | 2015-03-30 | 2016-11-04 | 一般財団法人電力中央研究所 | Method of manufacturing integrated reference electrode and integrated reference electrode |
| WO2019049945A1 (en) * | 2017-09-08 | 2019-03-14 | 国立大学法人三重大学 | Reference electrode |
| JPWO2019049945A1 (en) * | 2017-09-08 | 2020-08-20 | 国立大学法人三重大学 | Reference electrode |
| JP7154510B2 (en) | 2017-09-08 | 2022-10-18 | 国立大学法人三重大学 | reference electrode |
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