JPS58118953A - Preparation of gas sensitive element - Google Patents
Preparation of gas sensitive elementInfo
- Publication number
- JPS58118953A JPS58118953A JP85482A JP85482A JPS58118953A JP S58118953 A JPS58118953 A JP S58118953A JP 85482 A JP85482 A JP 85482A JP 85482 A JP85482 A JP 85482A JP S58118953 A JPS58118953 A JP S58118953A
- Authority
- JP
- Japan
- Prior art keywords
- gas
- sensitive element
- catalyst
- gas sensitive
- oxide semiconductor
- 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.)
- Granted
Links
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
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
Abstract
Description
【発明の詳細な説明】
１）発明の技術分野
本発明は感ガス素子の製造方法に係り、特に触媒を改良
した感ガス素子の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION 1) Technical Field of the Invention The present invention relates to a method for manufacturing a gas-sensitive element, and particularly to a method for manufacturing a gas-sensitive element using an improved catalyst.
２）従来技術及び問題点
従来、金属酸化物半導体を用いたガス検知素子は、ガス
が半導体表面に吸着した際に半導体表面の比抵抗が変化
することを利用したものである。2) Prior Art and Problems Conventionally, gas sensing elements using metal oxide semiconductors utilize the fact that the specific resistance of the semiconductor surface changes when gas is adsorbed to the semiconductor surface.
例えば、ｎａ１半導性を示すＺｎＯ，Ｓｎｏｗ 、Ｆ＠
Ｏｓ等に還元性ガスが接触すると抵抗値は減少し、また
酸化性ガスが吸着すると抵抗値は増加する。さらにＰ盤
半導性を示す金属酸化物半導体においては抵抗値の増減
は逆の関係を示す。金属酸化物半導体と各種ガスとの反
応性は、半導体表面温度、表面電子レベルの構造、気孔
率および気孔の大龜さ等により決まるが、一般には金属
酸化物半導体のみでは感ガス素子としては感度が小さい
２．そこで、Ｐｌ。For example, ZnO, Snow, F@ exhibiting na1 semiconductivity
When a reducing gas comes into contact with Os or the like, the resistance value decreases, and when an oxidizing gas is adsorbed, the resistance value increases. Furthermore, in a metal oxide semiconductor exhibiting P-disc semiconductor, the increase and decrease in resistance value exhibits an inverse relationship. The reactivity of metal oxide semiconductors with various gases is determined by the semiconductor surface temperature, structure at the surface electron level, porosity, pore size, etc., but in general, metal oxide semiconductors alone have insufficient sensitivity as gas-sensitive elements. is small 2. Therefore, Pl.
Ｐｄ等の貴金属触媒を酸化物半導体への添加、あるいは
、シリカ・アルミナ化合物等に担持させた担持触媒とし
て用いることＫより、感度を向上させる試みがなされて
いる。Attempts have been made to improve the sensitivity by adding a noble metal catalyst such as Pd to an oxide semiconductor or by using it as a supported catalyst supported on a silica/alumina compound or the like.
金属酸化物、半導体を用いたガス検知素子は各種ガス費
報器としての用途が広い、特に家庭用燃料として用いら
れるＬＰガスおよび都市ガスレタン土成分あるいは、メ
タン、水素を主成分とする）のガス漏れ検出用として用
いられる。Gas detection elements using metal oxides and semiconductors have a wide range of uses as various gas meter, especially for gases such as LP gas and city gas (mainly composed of methane, hydrogen, etc.) used as household fuel. Used for leak detection.
さらには、ガスおよび液体燃料の不光全燃焼に共なう一
酸化炭素の発生が社会問題となりつつあり、−酸化炭素
検出用としても需要が高まっている。Furthermore, the generation of carbon monoxide due to the complete combustion of gas and liquid fuels is becoming a social problem, and demand is increasing for use in detecting carbon oxide.
３）発明の目的
本発明は、ＬＰガス、都市ガスおよび一酸化炭素ガスに
対し優れた感度を有する感ガス素子の製造方法を提供す
ることを目的とする。3) Purpose of the Invention The object of the present invention is to provide a method for manufacturing a gas-sensitive element having excellent sensitivity to LP gas, city gas, and carbon monoxide gas.
４）発明の［要
本発明はＶ、 Ｃｒ、 Ｍｎ、 Ｃｏ、 Ｎｉ、 Ｃｕ
、 Ｍｏ、 Ｗのうち少なくとも一種の金属元素とＴＩ
Ｏ，とを混合してなる触媒を感ガス能を有する金属酸化
物半導体に混合してなるガス感応体を一対の電極間に設
ける事を％徴とした感ガス素子の製造方法、および感ガ
ス能を有する金属酸化物半導体からなるガス感応素体表
面に、Ｖ、 Ｃｒ、 Ｍｎ、 Ｃｏ、 Ｎｉ、 Ｃｕ、
Ｍｏ、 Ｗのうち少なくとも一種の金属元素とＴＩＯ
２とを混合してなる触媒層を設ける事を特徴とした感ガ
ス素子の製造方法である。4) The essential features of the invention are V, Cr, Mn, Co, Ni, Cu
, Mo, and at least one metal element among W and TI
A method for producing a gas-sensitive element, the method comprising disposing a gas-sensitive element formed by mixing a catalyst formed by mixing O, with a metal oxide semiconductor having gas-sensitive ability between a pair of electrodes, and a gas-sensitive element. V, Cr, Mn, Co, Ni, Cu,
At least one metal element among Mo and W and TIO
This is a method for manufacturing a gas-sensitive element characterized by providing a catalyst layer made of a mixture of 2 and 3.
なお、実用−ヒＴ ＩＯ２に対する前記金属の量は０．
１〜２０ ｗｔ 襲が好ましい。すなわち、担持される
金属蓋が０．１ ｗ を−未満では充分な感度を得るこ
とが困難となり、また２０ｗｔ ｌを超えると触媒効果
が充分に表われない。In addition, the amount of the above-mentioned metal with respect to practical human T IO2 is 0.
1 to 20 wt is preferred. That is, if the supported metal cap is less than 0.1 wtl, it will be difficult to obtain sufficient sensitivity, and if it exceeds 20 wtl, the catalytic effect will not be sufficiently exhibited.
また本発明方法において用いる感ガス能を有する金属酸
化物半導体としては、通常感ガス木刀にすべて便用でき
、ＺｎＯ，５ｆｌｏ、 、 Ｆｅ２０１やこれらに添加
物を加えたものも使えることはもちろんのことである。Furthermore, as the metal oxide semiconductor having gas-sensitive ability used in the method of the present invention, all of the usual gas-sensitive wooden swords can be conveniently used, and it goes without saying that ZnO, 5flo, , Fe201, and those with additives added thereto can also be used. It is.
例えば象加物を加え九ものとしてＺｎＯに５ｔ）Ｏ，、
人＆Ｏｓ 、 Ｆ ｅｔ０３ 、 Ｓ ｎｏ、
、 Ｔ ｉＯｚ 、％ Ｏ＠ 、Ｎｂ、ｏ、、
’ＷＯ＠ 。For example, adding elephant material to ZnO and adding 5t) O,,
Person&Os, F et03, S no,
, T iOz , % O@ , Nb, o, ,
'WO@.
Ｍｏｂ＠などを加えたものやＳｎＯ２にＳｂ、Ｏ，、Ａ
Ｊ、Ｏ，、Ｔｌ０１゜Ｖ２Ｏ６、Ｎｂ！ｏ＠ 、 ＷＯ
３、Ｍｏｂ、などがあり、通常ガスに感じで抵抗を変え
るいわゆる金属酸化物半導体は総て１史うことかできる
う
５）発明の実施例
以下本発明方法を具体例により詳細に説明する。Mob@, etc., and SnO2 plus Sb, O,, A
J, O,, Tl01°V2O6, Nb! o@, WO
3. Mob, etc., and all the so-called metal oxide semiconductors that change resistance depending on the feeling of gas have a long history.5) Examples of the Invention The method of the present invention will be explained in detail below using specific examples.
例えば第１図及び第２図に断面的に示すごとく、筒状絶
縁体ｔｌ）外局面に一対の電極ｔ２）を胸し、紡記筒状
絶縁体（１）および電享（２）を被覆するようにガス感
応体（３）もしくはガス感応素体（濁が設けられ、本発
明に係る感ガス素子（４）が得られる。なお、本発明に
係る触媒は第１図に示す如くガス感応体（３）中に浸入
する事も可能であるが、高温安定性、経時特性等の点か
ら第２図に示す如くガス感応素体（，１）表面に触媒層
（５）として設けられる。また前記のように構成された
感ガス素子（４）は例えば第３図に斜視的に示す如くビ
ン足止に組み立てられる。なお、第３図中（６）はヒー
タ用リード線を、（力は電極用リード線を、（８）は加
熱用ヒータを、（９）は絶縁板をそれぞれ示す
また、例えば第２図の如き本発明方法に係る感カス素子
は以下の如く製造される。For example, as shown in cross section in Figs. 1 and 2, a pair of electrodes t2) are placed on the outer surface of a cylindrical insulator tl), and a spinning cylindrical insulator (1) and an electric conductor (2) are covered. As shown in FIG. Although it is possible to penetrate into the gas-sensitive element body (3), from the viewpoint of high temperature stability, aging characteristics, etc., it is provided as a catalyst layer (5) on the surface of the gas-sensitive element body (1) as shown in FIG. Further, the gas-sensitive element (4) configured as described above is assembled into a bottle stopper, for example, as shown perspectively in Fig. 3. In Fig. 3, (6) indicates the heater lead wire (8) represents a heater for heating, and (9) represents an insulating plate. For example, a gas-sensitive element according to the method of the present invention as shown in FIG. 2 is manufactured as follows.
捷ずＴ１０．を所定量秤量し、前記金属の塩化物あるい
は硝酸化物の所定濃度水溶液中に加え、よくかくはん後
放置する。放置後１００Ｃで充分乾燥した後、粉末化し
電気炉で約３００〜７００Ｃで焼成することにより触媒
用材料が得られる。次にガス感応素体とし、て例えば金
属酸化物半導体としてＺｎＯと５ｂ２（、）、を所定量
秤取し、メチルセルロース等のバインダーを適当量加え
てボールミルなどで一定時間混合しペーストとする。こ
のペーストを前記電極（２）を有する筒状絶縁基体（１
）表面に塗布し、乾燥後３００−１０００Ｃで焼成する
。次に前記ガス感応素体（画表面に前記触媒のペースト
を塗布、乾燥した後３００−７００Ｃで焼成することに
より触媒層（５）を形成する。。Selection T10. A predetermined amount of is weighed out, added to an aqueous solution of a predetermined concentration of the metal chloride or nitrate, stirred thoroughly, and then left to stand. After being left to stand, it is sufficiently dried at 100C, then powdered and fired in an electric furnace at about 300 to 700C to obtain a catalyst material. Next, predetermined amounts of ZnO and 5b2 (, ) as metal oxide semiconductors are weighed out as a gas-sensitive element, an appropriate amount of a binder such as methylcellulose is added, and the mixture is mixed in a ball mill or the like for a predetermined time to form a paste. This paste is applied to the cylindrical insulating substrate (1) having the electrode (2).
) Coat on the surface, dry and then bake at 300-1000C. Next, a catalyst layer (5) is formed by applying a paste of the catalyst on the surface of the gas-sensitive element (image), drying it, and then firing it at 300-700C.
上記の如く製造した第２図の如き構造の感ガス素子（４
）は第３図の如く取り付けて使用される。The gas-sensitive element (4
) is installed and used as shown in Figure 3.
次に一ヒ述の如き方法によ知得た本発明に係る感ガス素
子について説明する。まず、ガス感応素体として、Ｚｎ
Ｏ（９６ｗｔ＊） −ｓｂ、ｏ、 （４ｗｔｌＧ）系酸
化物半導体として用い、各金属元素をＴｉｅ、に担持さ
せた触媒（Ｔｉ０１に対する各金属元素の担持量はＳＷ
ｔ＊）を用いた素子の各種還元性ガス２０００ｐｐｍに
対する感度を′＄１表に実施例として示し九。また、比
較例１〜３として、Ａ右０．担持金属触媒を用い九場合
と、比較例−４としてＴｉＯ２担体のみを用い九場合に
りいて示した。なお、感度はＲａ Ｉ ｒ／Ｒｇａ ｓ
（Ｒａ Ｉ ｒ ；空気中における抵抗値、Ｒｇａｓ
；ガス中における抵抗値）で示し、Ｒｇａｓは素子をガ
ス雰囲気中に置いて約１分後の値を用いた。まえ、素子
動作温度線約４０００である。Next, the gas-sensitive element according to the present invention, which was obtained by the method described above, will be explained. First, as a gas-sensitive element body, Zn
A catalyst used as an O(96wt*) -sb, o, (4wtlG)-based oxide semiconductor and supporting each metal element on Tie (the amount of each metal element supported on Ti01 is SW
The sensitivity of the element using t*) to 2000 ppm of various reducing gases is shown as an example in Table 9. In addition, as Comparative Examples 1 to 3, A right 0. Nine cases using a supported metal catalyst and nine cases using only a TiO2 carrier as Comparative Example-4 were shown. Note that the sensitivity is Ra I r/Rga s
(Ra I r ; resistance value in air, Rgas
;resistance value in gas), and Rgas used the value approximately 1 minute after placing the element in the gas atmosphere. First, the element operating temperature line is approximately 4000°C.
第 １ 表
以下余白
第 ２ 表
第１表から明らかなように、ＴｉＯ２担持効果は明らか
であり、本発明に係る素子は従来のＰｔ、 Ｐｄ、Ｒｈ
等の貴金属触媒を用いた素子よりも還元性ガスに付して
高感度を示し、特にＣ（Ｊ、 ＣＨ，に対する感度が増
大していることが％倣的である。As is clear from Table 1, the effect of supporting TiO2 is clear, and the element according to the present invention is similar to conventional Pt, Pd, Rh
It shows higher sensitivity to reducing gases than elements using noble metal catalysts such as, and it is particularly noteworthy that the sensitivity to C(J, CH, is increased).
さらに第２＆には、本素子の応答特性を示し丸。Furthermore, the second circle indicates the response characteristics of this device.
すなわち、応答時間５秒での抵抗変化を１分後の抵抗変
化に対する変化率（（Ｒａｉｒ−Ｒ”””）／（Ｒａｌ
ｒ−ａｓ
Ｒ３？＋５））刈００（＊）で示した。第２表より明ら
かなように、Ｈｌ 、 ＣＯ，Ｉ ５ｏ−Ｃ４Ｈ１（１
に対しては、いずれの触媒を用いた場合にも、１分後の
抵抗変化率の９４−以上の抵抗変化を示し、一般に検出
しにくいＣ）（４に対しては、やや低い値であるが、８
〇−以上の変化率を示すことがわかる。In other words, the resistance change at a response time of 5 seconds is expressed as the rate of change in resistance after 1 minute ((Rair-R""")/(Ral
r-as R3? +5)) Indicated by 00 (*). As is clear from Table 2, Hl, CO, I5o-C4H1(1
For C), whichever catalyst is used, the resistance change rate after 1 minute is 94 or more, and is generally difficult to detect (for C) (4, it is a slightly lower value). But 8
It can be seen that the rate of change is greater than or equal to 〇-.
また第１図に示す如き感ガス素子は例えば以下の如く製
造される。Further, the gas-sensitive element as shown in FIG. 1 is manufactured, for example, as follows.
すなわちＴｉ０１を所定量秤取し、前金属の塩化物もし
くは硝酸化物の所定濃度水溶中に加えよくかくはん後、
放置する。一定時間放置後１００ｔ：’で乾燥し、初析
して粉末を得る。これを電気炉で約３００〜７００Ｃで
涜成し触媒粉末を得る。一方別に半導体として例えばＺ
ｎＯを秤取し、これに必要量のｓｂ、ｏ。That is, a predetermined amount of Ti01 is weighed out, added to an aqueous solution containing a predetermined concentration of chloride or nitrate of the metal, and stirred well.
put. After being left for a certain period of time, it is dried at 100 t:' and pro-eutectoid to obtain a powder. This is agitated in an electric furnace at about 300 to 700 C to obtain a catalyst powder. On the other hand, as a semiconductor, for example, Z
Weigh out nO and add the required amount of sb and o to it.
など添加物を加え、これに前記触媒粉末を必豊量加え、
さらにバインダとしてメチルセルロース水溶液など加え
てボールミルなどで十分喪ぐ混合しペースト状とする。Add additives such as, add the necessary amount of the catalyst powder to this,
Furthermore, a methyl cellulose aqueous solution is added as a binder and thoroughly mixed using a ball mill or the like to form a paste.
このペーストを既にのべＩＦＩＩと同様な電極を有する
絶縁基体上に塗布し、乾燥後３００−１０００Ｇで焼成
する。これを適当なステム上に組立て、ヒータをとりつ
けて素子を得る。This paste is applied onto an insulating substrate that already has electrodes similar to IFII, and after drying, it is fired at 300-1000G. This is assembled on a suitable stem and a heater is attached to obtain an element.
なお上記の如くして得た感ガス素子も上記実施例と同様
に優れた感匿を示す事は確認された。しかしながら経時
変化を考慮した場合には第２図に示す如き構造とした方
がより好ましい。It was confirmed that the gas-sensitive element obtained as described above also exhibited excellent sensitivity similar to the above-mentioned example. However, in consideration of changes over time, a structure as shown in FIG. 2 is more preferable.
６）発明の効果
以上のように、本発明方法に係る感ガス素子は還元性ガ
スに高感度を有し、応答特性に優れており、さらに嵩温
安定であるために各種還元性ガス検出素子として有効で
あることがわかるう6) Effects of the Invention As described above, the gas-sensitive element according to the method of the present invention has high sensitivity to reducing gases, excellent response characteristics, and is stable at bulk temperature, so it can be used in various reducing gas detection elements. It can be seen that it is effective as
第１図及び第２図は本発明方法に係る感ガス素子の構造
例を示す断面図、第３図は本発明方法により得た感ガス
素子を用いた装置例を示す斜視図。
ｌ・・・筒状絶縁体、 ２・・・電極、３・・・ガ
ス感応体（ガス感応素体）、４・・・感ガス素子、
５・・・触媒層。
代理人 弁理士 則近慧佑（他１名）1 and 2 are cross-sectional views showing an example of the structure of a gas-sensitive element according to the method of the present invention, and FIG. 3 is a perspective view showing an example of a device using the gas-sensitive element obtained by the method of the present invention. l... Cylindrical insulator, 2... Electrode, 3... Gas sensitive body (gas sensitive element), 4... Gas sensitive element,
5... Catalyst layer. Agent Patent attorney Keisuke Norichika (1 other person)
Claims (1)
、 Ｍｏ、 Ｗのうち少なくとも一種の金属元素とｒｉ
へとを混合してなる触媒を感ガス能を有する金属酸化物
半導体に混合してなるガス感応体を一対の電極間に設け
る事を特徴とした感ガス素子の製造方法。 ２）感ガス能を有する金属酸化物半導体からなるガス感
応素体表面に、Ｖ、 Ｃｒ、 Ｍｎ、 Ｃｏ、 Ｎｌ、
Ｃｕ、 Ｍｏ、 Ｗのうち少なくとも一種の金属元素
とＴｉｅ、と全混合してなる触媒層を設ける事を％徴と
した感ガス素子の製造方法。[Claims] 1) V, Cr, Mn, Co, Ni, Cu
, Mo, and at least one metal element among W and ri
1. A method for manufacturing a gas-sensitive element, characterized in that a gas-sensing body made of a metal oxide semiconductor having a gas-sensing ability is provided between a pair of electrodes. 2) V, Cr, Mn, Co, Nl,
A method for manufacturing a gas-sensitive element, comprising providing a catalyst layer completely mixed with at least one metal element among Cu, Mo, and W and Tie.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP85482A JPS58118953A (en) | 1982-01-08 | 1982-01-08 | Preparation of gas sensitive element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP85482A JPS58118953A (en) | 1982-01-08 | 1982-01-08 | Preparation of gas sensitive element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58118953A true JPS58118953A (en) | 1983-07-15 |
| JPS6152419B2 JPS6152419B2 (en) | 1986-11-13 |
Family
ID=11485226
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP85482A Granted JPS58118953A (en) | 1982-01-08 | 1982-01-08 | Preparation of gas sensitive element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58118953A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6156951A (en) * | 1984-08-28 | 1986-03-22 | Nemoto Tokushu Kagaku Kk | Air pollution detecting element |
| DE3604594A1 (en) * | 1986-02-14 | 1987-08-20 | Schott Glaswerke | Thin-film gas sensors having high measuring sensitivity as multilayer systems based on dipped indium oxide layers for detection of gas traces in carrier gases |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3043892U (en) * | 1997-05-30 | 1997-12-02 | 株式会社間組 | Wiring equipment |
-
1982
- 1982-01-08 JP JP85482A patent/JPS58118953A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6156951A (en) * | 1984-08-28 | 1986-03-22 | Nemoto Tokushu Kagaku Kk | Air pollution detecting element |
| DE3604594A1 (en) * | 1986-02-14 | 1987-08-20 | Schott Glaswerke | Thin-film gas sensors having high measuring sensitivity as multilayer systems based on dipped indium oxide layers for detection of gas traces in carrier gases |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6152419B2 (en) | 1986-11-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4242303A (en) | Gas detecting element | |
| JPS58118953A (en) | Preparation of gas sensitive element | |
| WO1985004859A1 (en) | Composition | |
| JP3026523B2 (en) | Gas sensor | |
| JP3046387B2 (en) | Gas sensor | |
| JPH0444691B2 (en) | ||
| JP2922264B2 (en) | Gas sensor | |
| JP3171734B2 (en) | Carbon monoxide gas sensing element | |
| JPH08226909A (en) | Contact-combustion-type carbon monoxide gas sensor | |
| JPS604849A (en) | Nitrogen oxide detecting element | |
| JPS5950352A (en) | Detection element for nox | |
| JPS58113849A (en) | Semiconductor gas sensor | |
| JP2002139469A (en) | Gas detection element and gas detection device having the gas detection element | |
| JPS63279150A (en) | Semiconductor type gas sensor | |
| JPH07198651A (en) | Thin film type gas sensor | |
| JPS6363064B2 (en) | ||
| JPH0735716A (en) | Thick film gas sensor and manufacture thereof | |
| JP2726886B2 (en) | Contact combustion type carbon monoxide sensor | |
| JPS6011489Y2 (en) | gas sensing element | |
| JPH02263145A (en) | Semiconductor type gas sensor | |
| JPS5840696B2 (en) | gas sensing element | |
| JP2575479B2 (en) | Gas sensor | |
| JPS6128932B2 (en) | ||
| JPH0390848A (en) | Gas sensor | |
| JPS58624B2 (en) | gas sensing element |