JP3928510B2

JP3928510B2 - Conductive sensor, method of manufacturing the same, and apparatus having the same

Info

Publication number: JP3928510B2
Application number: JP2002210743A
Authority: JP
Inventors: 幸生野村; 康之貫名; あづさ志賀
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2002-07-19
Filing date: 2002-07-19
Publication date: 2007-06-13
Anticipated expiration: 2022-07-19
Also published as: JP2004053395A

Description

【０００１】
【発明の属する技術分野】
本発明は、ピロリル基を含有する化学吸着膜を形成後ピロリル基間で共役系を形成した導電性膜が、その雰囲気の変動により導電率が変動することを利用した導電センサーに関する。
【０００２】
【従来の技術】
従来から有機系の導電性膜として、ポリピロールが知られている。これらは、ダイオードや電界効果トランジスタ等のエレクトロニクスデバイスや、エレクトロクロミック素子、光メモリ素子などオプトエレクトロニクスデバイス等に応用されているが、最近ではその雰囲気により導電性が変化することを利用した各種センサーに利用されつつある。
【０００３】
【発明が解決しようとする課題】
しかしながら、この膜を各種センサーに用いる場合、導電性を有する部分のほとんどが膜内部に形成されるため、表面の雰囲気による導電率の変化は小さい、つまり感度が低いという課題があった。また、導電膜の密着性が弱いため、センサーの信頼性に課題があった。
【０００４】
本発明はこの課題を解決するものであり、少なくともピロリル基を有するシラン化合物をシロキサン結合を介して基板表面に固定化し、さらにピロリル基間で共役系を形成した導電膜を各種センサーに用いる場合、導電性を有する共役系を形成したピロール基部分が表面に露出するため、表面の雰囲気による導電率の変化が大きい、つまり感度が高いセンサーとなる。また、その導電膜は化学結合により固定化されるので、信頼性の優れたセンサーとなる。
【０００５】
【課題を解決するための手段】
前記課題を解決するために、本発明の導電センサーは、２つの電極を有する基板表面の少なくとも電極間に、少なくともピロリル基を有するシラン化合物をシロキサン結合を介して基板表面に固定化し、さらにピロリル基間で共役系を形成した膜を有する、その雰囲気の変動により２つの電極間の導電率が変動する構成である。
【０００６】
これによって、導電性を有する共役系を形成したピロール基部分が表面に露出するため、表面の雰囲気による導電率の変化が大きい、つまり感度が高いセンサーとなる。また、その導電膜は化学結合により固定化されるので、信頼性の優れたセンサーとなる。
【０００７】
【発明実施の形態】
請求項１に記載の発明は、２つの電極を有する基板表面の少なくとも電極間に、少なくともピロリル基を有するシラン化合物をシロキサン結合を介して基板表面に固定化し、さらにピロリル基間で共役系を形成した膜を有する、その雰囲気の変動により２つの電極間の導電率が変動する構成の導電センサーにすることにより、導電性を有する共役系を形成したピロール基部分が表面に露出するため、表面の雰囲気による導電率の変化が大きい、つまり感度が高いセンサーとなる。また、その導電膜は化学結合により固定化されるので、信頼性の優れたセンサーとなる。
【０００８】
請求項２に記載の発明は、請求項１に記載の２つの電極をポリピロールもしくはその誘導体にすることにより、本発明の膜のピロール基部分と、ポリピロール電極のピロール基部分が共役系を形成し、膜と電極が電気的に導通するので、電極を通じて、その雰囲気の変動により生じる２つの電極間の導電率が変動を測定できる。
【０００９】
請求項３に記載の発明は、請求項１または２に記載の２つの電極を金、銀、白金、銅のいずれかもしくはそれらの合金にすることにより、本発明の膜のピロール基部分が、電極金属と共役結合を形成し、膜と電極が電気的に導通するので、電極を通じて、その雰囲気の変動により生じる２つの電極間の導電率が変動を測定できる。
【００１０】
請求項４に記載の発明は、２つの電極を有し、少なくともその電極表面上にポリピロール膜もしくはその誘導体膜を有する基板表面の少なくとも電極間に、少なくともピロリル基を有するシラン化合物をシロキサン結合を介して基板表面に固定化し、さらにピロリル基間で共役系を形成した膜を有する、その雰囲気の変動により２つの電極間の導電率が変動する構成と導電センサーとすることにより、本発明の膜のピロール基部分と、電極上のポリピロールのピロール基部分が共役系を形成し、膜と電極がポリピロールを介し電気的に導通するので、電極を通じて、その雰囲気の変動により生じる２つの電極間の導電率が変動を測定できる。
【００１１】
請求項５に記載の発明は、請求項１から４のいずれか１項に記載のピロリル基を有するシラン化合物をシロキサン結合を介して基板表面に固定化し、さらにピロリル基間で共役系を形成した膜が単分子膜であることにより、膜の表面側にピロリル基が固定化され、表面に露出するので、高感度の導電センサーとなる。
【００１２】
請求項６に記載の発明は、請求項１から５のいずれか１項に記載のピロニル基の窒素原子が表面に露出していることにより、膜の表面側にピロリル基の窒素原子が固定化され、表面に露出するので、高感度の導電センサーとなる。
【００１３】
請求項７に記載の発明は、請求項１から６のいずれか１項に記載の基板がガラスであることにより、本発明の膜および電極が外界と絶縁されるので、電極間の導電率を測定することで、導電センサーとなる。
【００１４】
請求項８に記載の発明は、２つの電極を有する基板表面の少なくとも電極間に、少なくともピロリル基を有するシラン化合物を気相もしくは液相で接触させる工程と、基板表面に固定化されたピロリル基を有するシラン化合物間でピロリル基の共役系を形成する工程を少なくとも含むことにより、その雰囲気の変動により２つの電極間の導電率が変動する導電センサーを製造できる。
【００１５】
請求項９に記載の発明は、２つの電極を有する基板表面の電極に、少なくともその電極表面上にポリピロール膜もしくはその誘導体膜を設ける工程と、その電極間に少なくともピロリル基を有するシラン化合物を気相もしくは液相で接触させる工程と、基板表面に固定化されたピロリル基を有するシラン化合物間でピロリル基の共役系を形成する工程を少なくとも含むことにより、本発明の膜のピロール基部分と、ポリピロール電極のピロール基部分が共役系を形成し、膜と電極が電気的に導通するので、電極を通じて、その雰囲気の変動により生じる２つの電極間の導電率が変動する導電センサーを製造できる。
【００１６】
請求項１０に記載の発明は、請求項８と９記載のシラン化合物がクロロシランであることにより、ピロリル基を有するシラン化合物が化学結合でもって基板表面に固定化される。
【００１７】
請求項１１に記載の発明は、請求項８と９に記載の、電極間に少なくともピロリル基を有するシラン化合物を気相もしくは液相で接触させる工程と、基板表面に固定化されたピロリル基を有するシラン化合物間でピロリル基の共役系を形成する工程の間に、過剰なシラン化合物を洗浄する工程を少なくとも含むことにより、ピロリル基間で共役系を形成した膜が単分子膜となるために、膜の表面側にピロリル基が固定化され、表面に露出するので、高感度の導電センサーとなる。
【００１８】
請求項１２に記載の発明は、請求項８と９に記載の、基板表面に固定化されたピロリル基を有するシラン化合物間でピロリル基の共役系を形成する工程が電解重合であることにより、高密度にピロリル基間で共役系を形成した膜となり、表面に露出するので、高感度の導電センサーとなる。
【００１９】
請求項１３から１５の発明は、２つの電極を有する基板表面の少なくとも電極間に、少なくともピロリル基を有するシラン化合物をシロキサン結合を介して基板表面に固定化し、さらにピロリル基間で共役系を形成した膜を有する測定装置であり、その雰囲気中のＣＯもしくはＮＯもしくは水素イオン濃度の変動により２つの電極間の導電率が変動する導電センサーの導電率を測定することにより、ＣＯもしくＮＯもしくは水素イオン濃度を測定できる。
【００２０】
なお、本発明に供されるピロリル基を有するシラン化合物としては一般式Ｃ４Ｈ４Ｎ−（ＣＨ２）ｎ−ＳｉＸ３（ただしＸはハロゲン、イソシアネート基、もしくはアルコキシ基。ｎは２以上の整数）で示される直鎖状化合物が基板との反応活性が高く、有効である。特に、Ｘがクロル基の場合は反応活性がより高く、特に有効である。また、構造としては（化１）、（化２）、（化３）に示す１位、２位、３位のものが有効であるが、特に３位のものは表面に窒素原子が露出するためにセンサーの感度が高くなる。
【００２１】
【化１】

【００２２】
【化２】

【００２３】
【化３】

【００２４】
また溶媒としては、活性水素を含まない非水系溶媒を用いるのが好ましく、水を含まない炭化水素系溶媒、フッ化炭素系溶媒、シリコーン系溶媒などを用いることが可能である。なお、石油系の溶剤の他に具体的に使用可能なものは、石油ナフサ、ソルベントナフサ、石油エーテル、石油ベンジン、イソパラフィン、ノルマルパラフィン、デカリン、工業ガソリン、灯油、リグロイン、ジメチルミリコーン、フェニルシリコーン、アルキル変性シリコーン、ポリエステルシリコーンなどを挙げることができる。また、フッ化炭素系溶媒には、フロン系溶媒や、フロリナート（３Ｍ社製品）、アフルード（旭ガラス社製品）などがある。なお、これらは１種単独で用いてもよいし、よく混合するものなら２種以上を組み合わせてもよい。
【００２５】
さらに基板については、２つの電極を形成でき、しかも電極間が絶縁性を有しかつ表面水酸基を有するものがよく、ガラスが望ましい。またセラミックスでも同様である。また金属でも表面に絶縁性酸化皮膜を形成して絶縁性をもった２つの電極を形成したものでもよい。さらに電極と電極間の表面に表面水酸基を形成可能であるならばプラスチックでも適用可能である。
【００２６】
【実施例】
（実施例１）
導電センサーの作製法を図１に従って説明する。ピロリル基を有するシラン化合物１として、１−ピロリルオクチルトリクロロシランを、その溶媒２として、ヘキサメチルジシロキサンを用いた溶液に、２つの金電極３を有する石英基板４を、無水雰囲気下で１時間浸漬後、過剰な１−ピロリルオクチルトリクロロシランをクロロホルム５で洗浄した。このとき１−ピロリルオクチルトリクロロシランは、そのクロロ基とＡｕ電極領域外の石英基板上の水酸基が脱塩酸反応をおこして、シロキサン結合を介して石英基板に固定化される。また、そのピロリル基は、金電極と化学結合を形成する。この基板をさらに湿度雰囲気下で乾燥させると、隣接クロロ基同士が脱塩酸反応をおこして、１−ピロリルオクチルトリクロロシラン同士がシロキサン結合を介して重合する。不活性ガス雰囲気下で、無水過塩素酸リチウム０．０５ｍｏｌ／Ｌのアセトニトリル溶液中６に浸漬しながら、２つの電極間に電流密度１００μＡ／ｃｍ２となるように、走査速度１００ｍＶ／Ｓで電解重合した。この結果、ピロリル基は隣接どおしで重合をおこし、ポロピロール単分子膜７ができる。
【００２７】
この単分子膜を有する基板を、不活性ガス雰囲気中で２つの電極間に６０Ｈｚの交流をプローブとしての導電率を測定したところ６０ｍＳを示したが、この雰囲気にＣＯを導入し雰囲気濃度を１０ｐｐｍにしたところ、４５ｍＳとなったことから、この単分子膜を有する基板は導電センサーとして作用することがわかる。
【００２８】
同様にして、ＮＯ、メルカプタン、カルボン酸、アルデヒド、アルコール、ケトン等、有害物やにおいの成分なのどガスに対しても同様な作用があることがわかった。
【００２９】
また、水溶液中に浸漬すると、水素イオン濃度に対しても同様な作用があることがわかった。
【００３０】
（実施例２）
実施例１の２つの金電極を有する石英基板の代わりに、２つのポリピロール膜電極を有する石英基板にかえて同様にして導電センサーを作製した。このとき、１−ピロリルオクチルトリクロロシランは、そのピロリル基が、ポリピロール膜電極と重合する。この場合、単分子膜と電極間の導通が向上し、この単分子膜を有する基板を、不活性ガス雰囲気中で２つの電極間に６０Ｈｚの交流をプローブとしての導電率を測定したところ８０ｍＳを示した。
【００３１】
（実施例３）
実施例１の２つの金電極を有する石英基板の代わりに、その２つの金電極上にポリピロール膜を設けた石英基板にかえて同様にして導電センサーを作製した。この場合、単分子膜と電極間の導通が向上し、この薄膜を有する基板を、不活性ガス雰囲気中で２つの電極間に６０Ｈｚの交流をプローブとしての導電率を測定したところ８００ｍＳを示し、この雰囲気にＣＯを導入し雰囲気濃度を１０ｐｐｍにしたところ、６００ｍＳとなったことからセンサーの感度が大幅に向上した。
【００３２】
（実施例４）
実施例１の１−ピロリルオクチルトリクロロシランの代わりに、３−ピロリルオクチルトリクロロシランに代えて同様にして導電センサーを作製した。この場合、雰囲気物質と単分子膜との応答向上し、この単分子膜を有する基板を、不活性ガス雰囲気中で２つの電極間に６０Ｈｚの交流をプローブとしての導電率を測定したところ８５ｍＳを示し、この雰囲気にＣＯを導入し雰囲気濃度を１０ｐｐｍにしたところ、４０ｍＳとなったことからセンサーの感度が大幅に向上した。
【００３３】
【発明の効果】
以上のように、本発明によれば、少なくともピロリル基を有するシラン化合物をシロキサン結合を介して基板表面に固定化し、さらにピロリル基間で共役系を形成した導電膜を各種センサーに用いる場合、導電性を有する共役系を形成したピロール基部分が表面に露出するため、表面の雰囲気による導電率の変化が大きい、つまり感度が高いセンサーとなる。また、その導電膜は化学結合により固定化されるので、信頼性の優れたセンサーとなる。
【００３４】
そしてこれらの効果によって、高品質、高信頼性の導電センサーおよびそれを用いた測定装置を長期間にわたりを提供できることから本発明の効果は絶大である。
【図面の簡単な説明】
【図１】本発明の実施例１における導電センサーの作製法を示す概略図
【符号の説明】
１ピロリル基を有するシラン化合物
３金電極（電極）
４石英基板（基板）
７単分子膜（膜）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a conductive sensor utilizing the fact that the conductivity of a conductive film in which a conjugated system is formed between pyrrolyl groups after forming a chemisorbed film containing pyrrolyl groups varies depending on the atmosphere.
[0002]
[Prior art]
Conventionally, polypyrrole is known as an organic conductive film. These are applied to electronics devices such as diodes and field effect transistors, and optoelectronic devices such as electrochromic elements and optical memory elements. Recently, they are used for various sensors that use the change in conductivity depending on the atmosphere. It is being done.
[0003]
[Problems to be solved by the invention]
However, when this film is used for various sensors, since most of the conductive part is formed inside the film, there is a problem that the change in conductivity due to the atmosphere on the surface is small, that is, the sensitivity is low. Further, since the adhesion of the conductive film is weak, there is a problem in the reliability of the sensor.
[0004]
The present invention solves this problem, when a silane compound having at least a pyrrolyl group is immobilized on a substrate surface via a siloxane bond, and a conductive film in which a conjugated system is formed between pyrrolyl groups is used for various sensors. Since the pyrrole group portion in which the conjugated system having conductivity is formed is exposed on the surface, the change in conductivity due to the atmosphere on the surface is large, that is, the sensor has high sensitivity. Further, since the conductive film is fixed by chemical bonding, the sensor has excellent reliability.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problem, the conductive sensor of the present invention has a silane compound having at least a pyrrolyl group immobilized on a substrate surface via a siloxane bond between at least electrodes on the substrate surface having two electrodes, and further has a pyrrolyl group. It has a structure in which the conductivity between the two electrodes varies depending on the variation of the atmosphere having a film in which a conjugated system is formed.
[0006]
As a result, the pyrrole group portion in which a conjugated system having conductivity is exposed is exposed on the surface, so that the change in conductivity due to the atmosphere on the surface is large, that is, the sensor has high sensitivity. Further, since the conductive film is fixed by chemical bonding, the sensor has excellent reliability.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
According to the first aspect of the present invention, a silane compound having at least a pyrrolyl group is fixed to the substrate surface via a siloxane bond between at least electrodes on the substrate surface having two electrodes, and a conjugated system is formed between the pyrrolyl groups. Since the pyrrole group portion having a conductive conjugated system is exposed on the surface by using the conductive sensor having the structure in which the conductivity between the two electrodes varies due to the change in the atmosphere, the surface of the surface is exposed. The sensor has a large change in conductivity due to the atmosphere, that is, a sensor with high sensitivity. Further, since the conductive film is fixed by chemical bonding, the sensor has excellent reliability.
[0008]
In the second aspect of the invention, the pyrrole group portion of the film of the present invention and the pyrrole group portion of the polypyrrole electrode form a conjugated system by making the two electrodes according to the first aspect polypyrrole or a derivative thereof. Since the film and the electrode are electrically connected, the change in the conductivity between the two electrodes caused by the change in the atmosphere can be measured through the electrode.
[0009]
In the invention according to claim 3, by making the two electrodes according to claim 1 or 2 into one of gold, silver, platinum, copper, or an alloy thereof, the pyrrole group portion of the film of the present invention is Since a conjugate bond is formed with the electrode metal and the film and the electrode are electrically connected, the variation in the conductivity between the two electrodes caused by the variation in the atmosphere can be measured through the electrode.
[0010]
The invention according to claim 4 has two electrodes, and at least a silane compound having a pyrrolyl group is interposed via a siloxane bond between at least electrodes on the substrate surface having a polypyrrole film or a derivative film on the electrode surface. The film of the present invention has a structure in which the conductivity between the two electrodes varies due to the variation of the atmosphere and the conductive sensor, which has a film in which a conjugated system is formed between pyrrolyl groups. Since the pyrrole group part and the pyrrole group part of the polypyrrole on the electrode form a conjugated system, and the film and the electrode are electrically connected via the polypyrrole, the conductivity between the two electrodes caused by the change in the atmosphere through the electrode. Can measure variation.
[0011]
In the invention described in claim 5, the silane compound having the pyrrolyl group described in any one of claims 1 to 4 is immobilized on the substrate surface via a siloxane bond, and a conjugated system is formed between the pyrrolyl groups. Since the film is a monomolecular film, pyrrolyl groups are immobilized on the surface side of the film and exposed to the surface, so that a highly sensitive conductive sensor is obtained.
[0012]
The invention according to claim 6 is that the nitrogen atom of the pyronyl group according to any one of claims 1 to 5 is exposed on the surface, whereby the nitrogen atom of the pyrrolyl group is immobilized on the surface side of the film. And exposed to the surface, it becomes a highly sensitive conductive sensor.
[0013]
The invention according to claim 7 is that the substrate according to any one of claims 1 to 6 is made of glass, so that the film and the electrode of the present invention are insulated from the outside. By measuring, it becomes a conductive sensor.
[0014]
According to an eighth aspect of the present invention, there is provided a step of contacting a silane compound having at least a pyrrolyl group in a gas phase or a liquid phase between at least electrodes on a substrate surface having two electrodes, and a pyrrolyl group immobilized on the substrate surface. By including at least the step of forming a pyrrolyl group conjugated system between the silane compounds having the above, it is possible to manufacture a conductive sensor in which the conductivity between the two electrodes varies due to the variation in the atmosphere.
[0015]
According to the ninth aspect of the present invention, there is provided a step of providing a polypyrrole film or a derivative film thereof on at least the electrode surface of the electrode on the substrate surface having two electrodes, and a silane compound having at least a pyrrolyl group between the electrodes. A pyrrole group portion of the film of the present invention, comprising at least a step of contacting in a phase or a liquid phase, and a step of forming a pyrrolyl group conjugated system between silane compounds having a pyrrolyl group immobilized on the substrate surface; Since the pyrrole group part of the polypyrrole electrode forms a conjugated system and the film and the electrode are electrically connected, a conductive sensor in which the conductivity between the two electrodes caused by the change in the atmosphere can be produced through the electrode.
[0016]
In the invention described in claim 10, when the silane compound described in claims 8 and 9 is chlorosilane, the silane compound having a pyrrolyl group is immobilized on the substrate surface by a chemical bond.
[0017]
The invention according to claim 11 is the step of contacting the silane compound having at least a pyrrolyl group between the electrodes according to claims 8 and 9 in a gas phase or a liquid phase, and a pyrrolyl group immobilized on the substrate surface. In order for the film in which the conjugated system is formed between the pyrrolyl groups to be a monomolecular film by including at least the step of cleaning the excess silane compound during the process of forming the conjugated system of the pyrrolyl group between the silane compounds having Since a pyrrolyl group is immobilized on the surface side of the film and exposed on the surface, a highly sensitive conductive sensor is obtained.
[0018]
In the invention described in claim 12, the step of forming a conjugated system of pyrrolyl groups between silane compounds having pyrrolyl groups immobilized on the substrate surface according to claims 8 and 9 is electrolytic polymerization. It becomes a film in which a conjugated system is formed between pyrrolyl groups at high density and is exposed on the surface, so that a highly sensitive conductive sensor is obtained.
[0019]
In the inventions of claims 13 to 15, a silane compound having at least a pyrrolyl group is fixed to the substrate surface via a siloxane bond between at least electrodes on the surface of the substrate having two electrodes, and a conjugated system is formed between the pyrrolyl groups. Is a measuring device having a film formed by measuring the conductivity of a conductive sensor in which the conductivity between two electrodes varies depending on the concentration of CO, NO, or hydrogen ions in the atmosphere. Ion concentration can be measured.
[0020]
The silane compound having a pyrrolyl group used in the present invention is represented by the general formula C4H4N- (CH2) n-SiX3 (where X is a halogen, an isocyanate group, or an alkoxy group, n is an integer of 2 or more). The chain compound is effective because of its high reaction activity with the substrate. In particular, when X is a chloro group, the reaction activity is higher and it is particularly effective. In addition, the structures shown in (Chemical Formula 1), (Chemical Formula 2), and (Chemical Formula 3) are effective in the 1st, 2nd, and 3rd positions, but in the 3rd position, the nitrogen atom is exposed on the surface. This increases the sensitivity of the sensor.
[0021]
[Chemical 1]

[0022]
[Chemical 2]

[0023]
[Chemical 3]

[0024]
As the solvent, it is preferable to use a non-aqueous solvent that does not contain active hydrogen, and it is possible to use a hydrocarbon solvent, a fluorocarbon solvent, a silicone solvent, or the like that does not contain water. In addition to petroleum-based solvents, petroleum naphtha, solvent naphtha, petroleum ether, petroleum benzine, isoparaffin, normal paraffin, decalin, industrial gasoline, kerosene, ligroin, dimethyl millicorn, phenyl silicone , Alkyl-modified silicone, polyester silicone and the like. In addition, the fluorocarbon solvents include chlorofluorocarbon solvents, Fluorinert (product of 3M), Afludo (product of Asahi Glass). In addition, these may be used individually by 1 type and may mix 2 or more types as long as it mixes well.
[0025]
Further, as the substrate, it is preferable that two electrodes can be formed and that the electrodes have insulating properties and have surface hydroxyl groups, and glass is desirable. The same applies to ceramics. Alternatively, a metal may be used in which an insulating oxide film is formed on the surface to form two insulating electrodes. Further, plastic can be applied as long as a surface hydroxyl group can be formed on the surface between the electrodes.
[0026]
【Example】
Example 1
A method for manufacturing the conductive sensor will be described with reference to FIG. A quartz substrate 4 having two gold electrodes 3 in a solution using 1-pyrrolyloctyltrichlorosilane as a silane compound 1 having a pyrrolyl group, hexamethyldisiloxane as a solvent 2 thereof, and 1 in an anhydrous atmosphere. After immersion for an hour, excess 1-pyrrolyloctyltrichlorosilane was washed with chloroform 5. At this time, 1-pyrrolyloctyltrichlorosilane is immobilized on the quartz substrate through a siloxane bond through a dehydrochlorination reaction between the chloro group and the hydroxyl group on the quartz substrate outside the Au electrode region. The pyrrolyl group forms a chemical bond with the gold electrode. When this substrate is further dried under a humidity atmosphere, adjacent chloro groups undergo a dehydrochlorination reaction, and 1-pyrrolyloctyltrichlorosilane is polymerized via a siloxane bond. Electropolymerization at a scanning speed of 100 mV / S so that the current density is 100 μA / cm 2 between the two electrodes while being immersed in an acetonitrile solution of 0.05 mol / L anhydrous lithium perchlorate in an inert gas atmosphere. did. As a result, the pyrrolyl group is polymerized adjacent to each other, and a polypyrrole monomolecular film 7 is formed.
[0027]
When the conductivity of the substrate having this monomolecular film was measured with an alternating current of 60 Hz as a probe between two electrodes in an inert gas atmosphere, 60 mS was shown. CO was introduced into this atmosphere and the atmospheric concentration was 10 ppm. As a result, since it was 45 mS, it can be seen that the substrate having this monomolecular film acts as a conductive sensor.
[0028]
Similarly, it has been found that NO, mercaptans, carboxylic acids, aldehydes, alcohols, ketones and the like have similar effects on toxic gases such as harmful substances and odor components.
[0029]
It was also found that when immersed in an aqueous solution, the same effect was obtained on the hydrogen ion concentration.
[0030]
(Example 2)
Instead of the quartz substrate having two gold electrodes in Example 1, a conductive sensor was produced in the same manner in place of the quartz substrate having two polypyrrole film electrodes. At this time, the pyrrolyl group of 1-pyrrolyloctyltrichlorosilane is polymerized with the polypyrrole film electrode. In this case, the conduction between the monomolecular film and the electrode is improved, and when the conductivity of the substrate having this monomolecular film is measured using a 60 Hz alternating current probe between the two electrodes in an inert gas atmosphere, 80 mS is obtained. Indicated.
[0031]
(Example 3)
Instead of the quartz substrate having two gold electrodes in Example 1, a conductive sensor was produced in the same manner in place of the quartz substrate in which a polypyrrole film was provided on the two gold electrodes. In this case, conduction between the monomolecular film and the electrode is improved, and when the conductivity of the substrate having this thin film is measured with a 60 Hz alternating current probe between the two electrodes in an inert gas atmosphere, it shows 800 mS, When CO was introduced into this atmosphere and the atmospheric concentration was 10 ppm, the sensitivity of the sensor was greatly improved because it became 600 mS.
[0032]
Example 4
Instead of 1-pyrrolyloctyltrichlorosilane in Example 1, a conductive sensor was produced in the same manner instead of 3-pyrrolyloctyltrichlorosilane. In this case, the response between the atmospheric substance and the monomolecular film was improved, and when the conductivity of the substrate having this monomolecular film was measured using a 60 Hz alternating current probe between two electrodes in an inert gas atmosphere, 85 mS was obtained. As shown in the figure, when CO was introduced into the atmosphere to make the atmosphere concentration 10 ppm, the sensitivity of the sensor was greatly improved because it became 40 mS.
[0033]
【The invention's effect】
As described above, according to the present invention, when a conductive film in which a silane compound having at least a pyrrolyl group is immobilized on a substrate surface through a siloxane bond and a conjugated system is formed between pyrrolyl groups is used for various sensors, Since the pyrrole group portion having a conjugated system having a property is exposed on the surface, the sensor has a large change in conductivity depending on the surface atmosphere, that is, a high sensitivity. Further, since the conductive film is fixed by chemical bonding, the sensor has excellent reliability.
[0034]
Since these effects can provide a high-quality, highly reliable conductive sensor and a measuring apparatus using the same over a long period of time, the effects of the present invention are enormous.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a method for producing a conductive sensor in Example 1 of the present invention.
1 Silane compound having a pyrrolyl group 3 Gold electrode (electrode)
4 Quartz substrate (substrate)
7 Monomolecular film (film)

Claims

Variation of the atmosphere having a film in which a silane compound having at least a pyrrolyl group is fixed to the substrate surface via a siloxane bond between at least electrodes on the substrate surface having two electrodes and a conjugated system is formed between the pyrrolyl groups. Conductivity sensor in which conductivity between two electrodes varies due to

The conductive sensor according to claim 1, wherein the two electrodes are polypyrrole or a derivative thereof.

3. The conductive sensor according to claim 1, wherein the two electrodes are gold, silver, platinum, copper, or an alloy thereof.

A silane compound having at least a pyrrolyl group is immobilized on a substrate surface via a siloxane bond between at least electrodes on a substrate surface having two electrodes and at least a polypyrrole film or a derivative film on the electrode surface. A conductive sensor having a film in which a conjugated system is formed between groups, in which the conductivity between two electrodes fluctuates due to changes in the atmosphere.

5. The film according to claim 1, wherein the silane compound having a pyrrolyl group is immobilized on a substrate surface through a siloxane bond, and a film in which a conjugated system is formed between the pyrrolyl groups is a monomolecular film. The conductive sensor described in 1.

6. The conductive sensor according to claim 5, wherein the nitrogen atom of the pyronyl group is exposed on the surface.

The conductive sensor according to any one of claims 1 to 6, wherein the substrate is made of glass.

A step of contacting a silane compound having at least a pyrrolyl group in a gas phase or a liquid phase between at least electrodes on a substrate surface having two electrodes, and a pyrrolyl group between the silane compound having a pyrrolyl group immobilized on the substrate surface. A method for producing a conductive sensor, comprising at least a step of forming a conjugated system, wherein the conductivity between two electrodes varies due to variation in the atmosphere.

A step of providing a polypyrrole film or a derivative film thereof on at least the electrode surface on an electrode on a substrate surface having two electrodes, and a step of contacting a silane compound having at least a pyrrolyl group between the electrodes in a gas phase or a liquid phase A method for producing a conductive sensor, comprising at least a step of forming a pyrrolyl group conjugated system between silane compounds having a pyrrolyl group immobilized on a substrate surface, wherein the conductivity between the two electrodes varies due to variation in the atmosphere.

10. The method for producing a conductive sensor according to claim 8 or 9, wherein the silane compound is chlorosilane.

Between a step of contacting a silane compound having at least a pyrrolyl group between electrodes in a gas phase or a liquid phase and a step of forming a pyrrolyl group conjugated system between silane compounds having a pyrrolyl group immobilized on the substrate surface, 10. The method for producing a conductive sensor according to claim 8, further comprising at least a step of cleaning excess silane compound.

10. The method for producing a conductive sensor according to claim 8, wherein the step of forming a pyrrolyl group conjugated system between silane compounds having a pyrrolyl group immobilized on the substrate surface is electrolytic polymerization.

A silane compound having at least a pyrrolyl group is fixed to the substrate surface via a siloxane bond between at least electrodes on the substrate surface having two electrodes, and further includes a film in which a conjugated system is formed between the pyrrolyl groups. An apparatus that measures the CO concentration by measuring the conductivity of a conductive sensor in which the conductivity between two electrodes varies due to variation in the CO concentration.

A silane compound having at least a pyrrolyl group is fixed to the substrate surface via a siloxane bond between at least electrodes on the substrate surface having two electrodes, and further includes a film in which a conjugated system is formed between the pyrrolyl groups. A device that measures the NO concentration by measuring the conductivity of a conductive sensor in which the conductivity between two electrodes varies due to the variation in NO concentration.

A silane compound having at least a pyrrolyl group is fixed to the substrate surface via a siloxane bond between at least electrodes on the substrate surface having two electrodes, and further includes a film in which a conjugated system is formed between the pyrrolyl groups. An apparatus that measures the hydrogen ion concentration by measuring the conductivity of a conductive sensor in which the conductivity between two electrodes varies due to the variation of the hydrogen ion concentration.