CA1054224A - Method for applying electrodes to ceramic electrochemical gas analysers - Google Patents
Method for applying electrodes to ceramic electrochemical gas analysersInfo
- Publication number
- CA1054224A CA1054224A CA234,545A CA234545A CA1054224A CA 1054224 A CA1054224 A CA 1054224A CA 234545 A CA234545 A CA 234545A CA 1054224 A CA1054224 A CA 1054224A
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- CA
- Canada
- Prior art keywords
- layer
- metal
- electrode
- substrate
- platinum
- 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.)
- Expired
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- 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
- G01N27/4075—Composition or fabrication of the electrodes and coatings thereon, e.g. catalysts
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- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Biochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Molecular Biology (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Measuring Oxygen Concentration In Cells (AREA)
- Continuous Casting (AREA)
- Investigating And Analyzing Materials By Characteristic Methods (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
This specification discloses an electrochemical gas sensor having a zirconia substrate and electrodes each comprising a thin substantially continuous layer of platinum securely bonded to the substrate and a relatively thicker electrically conductive metal bonded to said thin layer. In one form the thicker metal comprises a layer of porous platinum bonded to said thin layer, the thin layer being from .08µm and 1.5µm to 500µm thick. In an alternative form the thicker metal comprises a fine electrically platinum wire bonded to the thin layer by a similar thin layer of platinum applied over the wire. A method of applying the electrodes to the substrate is also disclosed.
This specification discloses an electrochemical gas sensor having a zirconia substrate and electrodes each comprising a thin substantially continuous layer of platinum securely bonded to the substrate and a relatively thicker electrically conductive metal bonded to said thin layer. In one form the thicker metal comprises a layer of porous platinum bonded to said thin layer, the thin layer being from .08µm and 1.5µm to 500µm thick. In an alternative form the thicker metal comprises a fine electrically platinum wire bonded to the thin layer by a similar thin layer of platinum applied over the wire. A method of applying the electrodes to the substrate is also disclosed.
Description
This invention relates to a method of applying to solid ceramic electrolyte members, such as zirconia, electrodes of suitable noble metals such as platinum, palladium, gold or silver, in the manufacture or repair of sensors suitable for use in the analysis of gases such as oxygen. The invention also applies to the sensor produced by the method.
Gas sensors of the type with which the present in~ention is concerned are widely used in the measurement of oxygen content in gases as a means of monitoring the efficiency of a combustion process or the suitability of a gas for use for other purposes such as an inert atmosphere. The main field of interest to the applicant is the iron and steel industry but such sensors are used in other areas such as the brick kilns, incinerators, automobile exhausts, etc.
Platinum electrodes for stabilised zirconia electrolyte electrochemical oxygen gas analysers are currently prepared by painting platinum paste comprising a suspension of finely divided platinum in an organic vehicle onto the zirconia electrolyte, drying in air and then firing in oxidising atmospheres to around 1000C to produce a sintered porous platinum electrode. In service, these electrodes are prone to peel off the zirconia substrate. The reasons for this include:
~054;Z Z~
(1) Reducing gases cause recrystallisation of platinum with subsequent embrittlement. (2) Phase changes such as water boiling in porous struct~re. ~3) Combustion in the porous structure of unburnt reducing gases with excess oxygen. (4) Reaction of fine dust particles of fly ash, slag etc. with the zirconia after penetration into the porous platinum, resulting in breakage of the zirconia to platinum bond. (5) Volatilization of the platinum when ambient temperatures exceed about 1000C.
The object of this invention is to provide an electro-chemical gas sensor and a method of applying the electrodes thereof to a solid electrolyte substrate.
According to one aspect of the invention there is provided in an electrochemical gas sensor comprising a solid electrolyte substrate and an outer electrically-conducting porous electrode layer of electrode metal which in use of the sensor element is exposed to gases the oxygen content of which is to be measured, the improvement which comprises an electrically conducting intermediate layer of substantially continuous electrode metal bonded to the substrate and to the outer porous electrode layer and providing strong adherence of the porous electrode layer to the substrate, the porous electrode layer having a thickness of ahout 5 ~m to about 500 ~m and pr~viding the bulk of the electrical conductivity of the sensor, and the intermediate layer having a thickness of about 0.08 ~m to about 1.5 ~m thereby being sufficiently thin to permit penetration of oxygen.
According to another aspect of the invention there is provided a method of applying an electrode to a solid electrolyte substrate comprising applying to the substrate ~,J: ~ - 3 -.i,.''' ~
1054Z;~4 a substantially continuous thin coating comprising electrode metal precursor having a thickness of from 0.08~m to l.5~m, treating said coating to form said electrode metal to bond said metal to said substrate, and bonding to said metal a layer of electrically conductive metal having thickness of from 5~m to 500~m.
In a preferred form the relatively thicker metal comprises a fine electrically conductive metal wire bonded to said thin layer.
Preferably the electrolyte is zirconia and the electrode metal is bright platinum. Where a porous electrode - 3a -B
is used, the electrode is fired platinum paste. Where wire is used the wire is similarly platinum.
The bright platinum may be from approximately 0.08~m to 1.5~m thick and preferably about l~m. The porous electrode is from 5~m up to about 500~m thick, although thicker electrodes may be used in very hot environments (about 1300C) where excessive platinum loss will occur. The platinum wire may range from 0.05mm to 0.125mm in diameter.
The lower limit for the thickness of the thin layer is fairly arbitrary and is dictated by the need for continuity, good electrical conductivity being an indicative parameter, while the upper limit is set by the need for a good mechanical bond to the electrolyte.
In practice, the sensor may comprise a closed end zirconia tube having an electrode according to the invention at least outside thereof. However the invention is equally applicable to sensors of any configuration.
In another form the invention provides a method of applying an electrode to a solid electrolyte substrate comprising applying to the substrate a substantially continuous thin coating of electrode metal, drying and firing said coating to bond said coating to said substrate, and bonding to said thin coating a relatively thicker electrically conductive metal.
In a preferred form the thicker metal comprises a layer of electrode metal paste applied to said fired thin coating, said paste layer being fired to form a porous electrode layer bonded to said thin coating.
In an alternative form, the thicker metal comprises a fine metal wire bonded to said thin coating by the application of a further thin coating of a similar electrode metal over said wire.
The thin layer is preferably bright platinum applied in the thickness range stated above and the firing temperature may be from 650 to 800C in a strongly oxidising atmosphere of air or oxygen. m e firing step comprises heating the layer from room temperature to a temperature in the above range over about 2 to 3 hours followed by soaking at the firing temperature for not less than about 20 minutes.
The thicker porous layer is preferably a platinum paste from 5~m to 500~m thick, and typically about lOO~m for low temperatures <1000C and 500~m for high temperatures. me firing of the paste layer comprises heating up to about 800 to 1000C over about 3 or 4 hours followed by soaking for not less than 20 minutes at the firing temperature.
me following preferred form of the process has ; been successfully tested by the inventors: (1) The application by painting of a precoat of a platinum organometallic compound ("bright platinum") onto the zirconia, air drying and firing in a stream of oxygen or air at 700C for 20 minutes. The temperature was raised slowly over 3 hours to avoid blistering. The layer was found to be continuous and strongly adhering.
A second coat can be applied if necessary to ensure continuity. (2) Onto the bright platinum layer was applied, by painting or dipping r a coating of platinum paste which was air dried and brought slowly over 4 hours to 850C in oxidising conditions and held at this temperature for 1 hour. The final electrode thickness was about 100~m. The thickness shou-ld not exceed about 500~m as above this thickness peeling may occur.
The precoat layer of bright platinum acted as a strongly adhering substrate to which the platinum paste layer was bonded. The top layer of platinum paste provided the bulk of the electrical conductivity of the electrode combination while the bright platinum layer improved the cell resistance allowing the use of cheaper low resistance readout equipment.
Being continuous, the bright platinum layer protects the zirconia from dust reaction but is thin enough not to impede penetration by oxygen or reducing gases whilst at the same time providing a strongly adhering substrate.
It will be appreciated that in prac~ice an electrode will be applied to the two sides of the electrolyte, one ~0S4ZZ4 electrode serving as a reference electrode and the other serving as the variable electrode.
Where the reference gas is air, the reference electrode may comprise a standard porous platinum electrode without the bright platinum base layer. Closed end zirconia tubes having an outer diameter of about 10 mm and an inner diameter of about 8 mm with electrodes according to the above description applied thereto were tested and found to have cell resistances ranging from 25 to 50Q, equilibrium output voltages at 700C for a calibration gas of from 48.0 to 61.5 mV and response times ranging from 15 to 180 secs. to reach greate-r than 94~ of the eguilibrium output. Thus, the parameters of the cells were found to be quite satisfactory.
In a modified form of the invention, the porous platinum layer is replaced by multiple turns of fine metal wire overlaying the thin coating of electrode metal. The wire is preferably bonded to the base coating by a further coating of electrode metal and serves to conduct the voltage signal developed on the electrode layer to a suitable measuring instrument. In each case, the electrode metal coating is applied in accordance with the conditions stipulated in the first embodiment.
In a preferred form the base metal and further coating are platinum applied in the manner and within the thickness range described in the first embodiment.
The wire diameter may be within a range of from 0.05 mm to 0.125 mm.
Tests have been conducted using 0.125 mm wire wound onto a closed end zirconia tube having an outer diameter of about 10 mm and an inner diameter of about 8 mm at five turns per millimeter over a length of about 1 cm. The performance of this arrangement was found to be particularly effective for reducing gas situations, that is, where the output of the cell is in the range 750-1300 m~ for a cell temperature in the range 600-1100C.
It has been found that cells constructed in this way have a very fast response time taking onl~ about one second to reach 1300 mV from 0 mV. The response time of this arrangement is faster than for the first embodiment due to the substantially lower surface area of the bright platinum electrode layer and the smooth nature of the surface exposed to the gas under test.
Since the fine wire is used to conduct the voltage signal in this alternative embodiment, the electrode metal need only be applied to that region of the tube or other refractory body that is exposed to the maximum temperature of the gas under test. Since the tip of the tube is exposed to the maximum temperature, the electrode and wire are applied to a short section adjacent the tip.
The length over which the wire should be wound depends on the diameter of the wire but may vary between about 3 and 10 mm.
lOS4ZZ4 ; The stated range for suitable wire diameter is fairly arbitrary, the lower limit being determined by the practical handling characteristics of the wire and the upper limit being determined by the desirability of keeping the diameter as small as possible. The stated upper limit has been selected having regard to the desirability to have as many points of contact with the platinum electrode as possible, so as to ensure proper transmission of the voltage signal developed on the electrode, and bearing in mind the desirability of not exceeding the dimensions of the first embodiment, so that the alternative is interchangeable with the first form. Of course, where the cell is larger, the wire diameter in excess of 0.125 may be practical.
While the invention has been described specifically in relation to zirconia electrolyte having a platinum electrode, the invention may be equally applicable to other electrolyte/electrode combinations.
Gas sensors of the type with which the present in~ention is concerned are widely used in the measurement of oxygen content in gases as a means of monitoring the efficiency of a combustion process or the suitability of a gas for use for other purposes such as an inert atmosphere. The main field of interest to the applicant is the iron and steel industry but such sensors are used in other areas such as the brick kilns, incinerators, automobile exhausts, etc.
Platinum electrodes for stabilised zirconia electrolyte electrochemical oxygen gas analysers are currently prepared by painting platinum paste comprising a suspension of finely divided platinum in an organic vehicle onto the zirconia electrolyte, drying in air and then firing in oxidising atmospheres to around 1000C to produce a sintered porous platinum electrode. In service, these electrodes are prone to peel off the zirconia substrate. The reasons for this include:
~054;Z Z~
(1) Reducing gases cause recrystallisation of platinum with subsequent embrittlement. (2) Phase changes such as water boiling in porous struct~re. ~3) Combustion in the porous structure of unburnt reducing gases with excess oxygen. (4) Reaction of fine dust particles of fly ash, slag etc. with the zirconia after penetration into the porous platinum, resulting in breakage of the zirconia to platinum bond. (5) Volatilization of the platinum when ambient temperatures exceed about 1000C.
The object of this invention is to provide an electro-chemical gas sensor and a method of applying the electrodes thereof to a solid electrolyte substrate.
According to one aspect of the invention there is provided in an electrochemical gas sensor comprising a solid electrolyte substrate and an outer electrically-conducting porous electrode layer of electrode metal which in use of the sensor element is exposed to gases the oxygen content of which is to be measured, the improvement which comprises an electrically conducting intermediate layer of substantially continuous electrode metal bonded to the substrate and to the outer porous electrode layer and providing strong adherence of the porous electrode layer to the substrate, the porous electrode layer having a thickness of ahout 5 ~m to about 500 ~m and pr~viding the bulk of the electrical conductivity of the sensor, and the intermediate layer having a thickness of about 0.08 ~m to about 1.5 ~m thereby being sufficiently thin to permit penetration of oxygen.
According to another aspect of the invention there is provided a method of applying an electrode to a solid electrolyte substrate comprising applying to the substrate ~,J: ~ - 3 -.i,.''' ~
1054Z;~4 a substantially continuous thin coating comprising electrode metal precursor having a thickness of from 0.08~m to l.5~m, treating said coating to form said electrode metal to bond said metal to said substrate, and bonding to said metal a layer of electrically conductive metal having thickness of from 5~m to 500~m.
In a preferred form the relatively thicker metal comprises a fine electrically conductive metal wire bonded to said thin layer.
Preferably the electrolyte is zirconia and the electrode metal is bright platinum. Where a porous electrode - 3a -B
is used, the electrode is fired platinum paste. Where wire is used the wire is similarly platinum.
The bright platinum may be from approximately 0.08~m to 1.5~m thick and preferably about l~m. The porous electrode is from 5~m up to about 500~m thick, although thicker electrodes may be used in very hot environments (about 1300C) where excessive platinum loss will occur. The platinum wire may range from 0.05mm to 0.125mm in diameter.
The lower limit for the thickness of the thin layer is fairly arbitrary and is dictated by the need for continuity, good electrical conductivity being an indicative parameter, while the upper limit is set by the need for a good mechanical bond to the electrolyte.
In practice, the sensor may comprise a closed end zirconia tube having an electrode according to the invention at least outside thereof. However the invention is equally applicable to sensors of any configuration.
In another form the invention provides a method of applying an electrode to a solid electrolyte substrate comprising applying to the substrate a substantially continuous thin coating of electrode metal, drying and firing said coating to bond said coating to said substrate, and bonding to said thin coating a relatively thicker electrically conductive metal.
In a preferred form the thicker metal comprises a layer of electrode metal paste applied to said fired thin coating, said paste layer being fired to form a porous electrode layer bonded to said thin coating.
In an alternative form, the thicker metal comprises a fine metal wire bonded to said thin coating by the application of a further thin coating of a similar electrode metal over said wire.
The thin layer is preferably bright platinum applied in the thickness range stated above and the firing temperature may be from 650 to 800C in a strongly oxidising atmosphere of air or oxygen. m e firing step comprises heating the layer from room temperature to a temperature in the above range over about 2 to 3 hours followed by soaking at the firing temperature for not less than about 20 minutes.
The thicker porous layer is preferably a platinum paste from 5~m to 500~m thick, and typically about lOO~m for low temperatures <1000C and 500~m for high temperatures. me firing of the paste layer comprises heating up to about 800 to 1000C over about 3 or 4 hours followed by soaking for not less than 20 minutes at the firing temperature.
me following preferred form of the process has ; been successfully tested by the inventors: (1) The application by painting of a precoat of a platinum organometallic compound ("bright platinum") onto the zirconia, air drying and firing in a stream of oxygen or air at 700C for 20 minutes. The temperature was raised slowly over 3 hours to avoid blistering. The layer was found to be continuous and strongly adhering.
A second coat can be applied if necessary to ensure continuity. (2) Onto the bright platinum layer was applied, by painting or dipping r a coating of platinum paste which was air dried and brought slowly over 4 hours to 850C in oxidising conditions and held at this temperature for 1 hour. The final electrode thickness was about 100~m. The thickness shou-ld not exceed about 500~m as above this thickness peeling may occur.
The precoat layer of bright platinum acted as a strongly adhering substrate to which the platinum paste layer was bonded. The top layer of platinum paste provided the bulk of the electrical conductivity of the electrode combination while the bright platinum layer improved the cell resistance allowing the use of cheaper low resistance readout equipment.
Being continuous, the bright platinum layer protects the zirconia from dust reaction but is thin enough not to impede penetration by oxygen or reducing gases whilst at the same time providing a strongly adhering substrate.
It will be appreciated that in prac~ice an electrode will be applied to the two sides of the electrolyte, one ~0S4ZZ4 electrode serving as a reference electrode and the other serving as the variable electrode.
Where the reference gas is air, the reference electrode may comprise a standard porous platinum electrode without the bright platinum base layer. Closed end zirconia tubes having an outer diameter of about 10 mm and an inner diameter of about 8 mm with electrodes according to the above description applied thereto were tested and found to have cell resistances ranging from 25 to 50Q, equilibrium output voltages at 700C for a calibration gas of from 48.0 to 61.5 mV and response times ranging from 15 to 180 secs. to reach greate-r than 94~ of the eguilibrium output. Thus, the parameters of the cells were found to be quite satisfactory.
In a modified form of the invention, the porous platinum layer is replaced by multiple turns of fine metal wire overlaying the thin coating of electrode metal. The wire is preferably bonded to the base coating by a further coating of electrode metal and serves to conduct the voltage signal developed on the electrode layer to a suitable measuring instrument. In each case, the electrode metal coating is applied in accordance with the conditions stipulated in the first embodiment.
In a preferred form the base metal and further coating are platinum applied in the manner and within the thickness range described in the first embodiment.
The wire diameter may be within a range of from 0.05 mm to 0.125 mm.
Tests have been conducted using 0.125 mm wire wound onto a closed end zirconia tube having an outer diameter of about 10 mm and an inner diameter of about 8 mm at five turns per millimeter over a length of about 1 cm. The performance of this arrangement was found to be particularly effective for reducing gas situations, that is, where the output of the cell is in the range 750-1300 m~ for a cell temperature in the range 600-1100C.
It has been found that cells constructed in this way have a very fast response time taking onl~ about one second to reach 1300 mV from 0 mV. The response time of this arrangement is faster than for the first embodiment due to the substantially lower surface area of the bright platinum electrode layer and the smooth nature of the surface exposed to the gas under test.
Since the fine wire is used to conduct the voltage signal in this alternative embodiment, the electrode metal need only be applied to that region of the tube or other refractory body that is exposed to the maximum temperature of the gas under test. Since the tip of the tube is exposed to the maximum temperature, the electrode and wire are applied to a short section adjacent the tip.
The length over which the wire should be wound depends on the diameter of the wire but may vary between about 3 and 10 mm.
lOS4ZZ4 ; The stated range for suitable wire diameter is fairly arbitrary, the lower limit being determined by the practical handling characteristics of the wire and the upper limit being determined by the desirability of keeping the diameter as small as possible. The stated upper limit has been selected having regard to the desirability to have as many points of contact with the platinum electrode as possible, so as to ensure proper transmission of the voltage signal developed on the electrode, and bearing in mind the desirability of not exceeding the dimensions of the first embodiment, so that the alternative is interchangeable with the first form. Of course, where the cell is larger, the wire diameter in excess of 0.125 may be practical.
While the invention has been described specifically in relation to zirconia electrolyte having a platinum electrode, the invention may be equally applicable to other electrolyte/electrode combinations.
Claims (13)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In an electrochemical gas sensor comprising a solid electrolyte substrate and an outer electrically-conducting porous electrode layer of electrode metal which in use of the sensor element is exposed to gases the oxygen content of which is to be measured, the improvement which comprises an electrically conducting intermediate layer of substantially continuous electrode metal bonded to the substrate and to the outer porous electrode layer and providing strong adherence of the porous electrode layer to the substrate, the porous electrode layer having a thickness of about 5 µm to about 500 µm and providing the bulk of the electrical conductivity of the sensor, and the intermediate layer having a thickness of about 0.08 µm to about 1.5 µm thereby being sufficiently thin to permit penetration of oxygen.
2. An electrochemical gas sensor as in claim 1 wherein the intermediate electrode metal layer is a noble metal.
3. An electrochemical gas sensor as in claim 1 wherein the intermediate electrode metal layer is a noble metal deposited on the substrate by firing a noble metal organo compound.
4. An electrochemical gas sensor as in claim 1 wherein the intermediate electrode metal layer is bright platinum.
5. An electrochemical gas sensor as in claim 1 wherein the outer porous electrode layer is a noble metal.
6. An electrochemical gas sensor as in claim 1 wherein the outer porous electrode layer is platinum deposited by firing a noble metal paste which has been applied to the intermediate electrode metal layer.
7. An electrochemical gas sensor as in claim 6 wherein the noble metal is platinum.
8. In a device for measuring the oxygen content of a gaseous mixture and having an electrochemical gas sensor which is exposed at one side to gases the oxygen content of which is to be measured, an improved sensor element comprising a solid electrolyte substrate supporting an outer electrically-conducting porous electrode layer of electrode metal on said one side of said element, said porous electrode layer being strongly adhered to the substrate by an electrically-conducting intermediate layer of substantially continuous electrode metal which is bonded to the substrate and to the porous electrode layer, the intermediate layer having a thickness of about 0.08 µm to about 1.5 µm thereby being sufficiently thin to permit penetration of oxygen and the porous electrode layer having a thickness of about 5 µm to about 500 µm and providing the bulk of the electrical conductivity of the sensor.
9. A method of applying an electrode to a solid electrolyte substrate comprising applying to the substrate a substantially continuous thin coating comprising electrode metal precursor having a thickness of from 0.08µm to 1.5µm, treating said coating to form said electrode metal to bond said metal to said substrate, and bonding to said metal a layer of electrically conductive metal having thickness of from 5µm to 500µm.
10. A method according to claim 9, wherein said thicker metal comprises a layer of electrode metal paste applied to said thin coating, said paste layer being fired to form a porous electrode layer bonded to said thin coating.
11. A method according to claim 9 wherein said thin electrode metal is a noble metal and the treatment of said metal precursor comprises drying and firing the coating to a temperature of from 650 to 800°C in a strongly oxidising atmosphere of air or oxygen over a period of 2 or 3 hours, and maintaining said temperature for not less than 20 minutes.
12. A method according to claim 10 wherein the metal paste is a noble metal and said firing step comprises heating the layer to a temperature of about 800°C to 1000°C over a period of about 3 to 4 hours and maintaining said tem-perature for not less than 20 minutes.
13. A method according to claim 11 or 12 wherein said noble metal is platinum.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU871474 | 1974-09-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1054224A true CA1054224A (en) | 1979-05-08 |
Family
ID=3699425
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA234,545A Expired CA1054224A (en) | 1974-09-02 | 1975-09-02 | Method for applying electrodes to ceramic electrochemical gas analysers |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JPS5152892A (en) |
| AU (1) | AU8441575A (en) |
| CA (1) | CA1054224A (en) |
| DE (1) | DE2539001A1 (en) |
| FR (1) | FR2283438A1 (en) |
| GB (2) | GB1505983A (en) |
| NL (1) | NL7510323A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5683570A (en) * | 1993-06-04 | 1997-11-04 | Dalhousie University | Gas detection method |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5310491A (en) * | 1976-07-16 | 1978-01-30 | Nippon Denso Co Ltd | Oxygen concentration detector |
| JPS5397896A (en) * | 1977-02-08 | 1978-08-26 | Hitachi Ltd | Oxygen concentration sensor and preparation thereof |
| US4107018A (en) * | 1977-09-01 | 1978-08-15 | Bendix Autolite Corporation | Solid electrolyte gas sensor having a protective bonding layer |
| US4253934A (en) * | 1979-04-17 | 1981-03-03 | General Motors Corporation | Aging treatment for exhaust gas oxygen sensor |
| FR2488408A1 (en) * | 1980-08-08 | 1982-02-12 | Carbonisation Entr Ceram | Oxygen determn. appts. esp. for exhaust gas from motor vehicles - using thin solid electrolyte coated on each side with thin metal film electrode to make probe which can be rapidly heated |
| JP5799649B2 (en) * | 2011-08-10 | 2015-10-28 | トヨタ自動車株式会社 | Manufacturing method of oxygen sensor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2206216C3 (en) * | 1972-02-10 | 1978-12-21 | Robert Bosch Gmbh, 7000 Stuttgart | Sensors for the determination of the oxygen content in exhaust gases, mainly from internal combustion engines, as well as processes for the production of such sensors |
-
1974
- 1974-09-02 AU AU84415/75A patent/AU8441575A/en not_active Expired
-
1975
- 1975-09-01 GB GB3590075A patent/GB1505983A/en not_active Expired
- 1975-09-02 JP JP50106478A patent/JPS5152892A/ja active Pending
- 1975-09-02 NL NL7510323A patent/NL7510323A/en not_active Application Discontinuation
- 1975-09-02 DE DE19752539001 patent/DE2539001A1/en active Pending
- 1975-09-02 CA CA234,545A patent/CA1054224A/en not_active Expired
- 1975-09-02 FR FR7526892A patent/FR2283438A1/en not_active Withdrawn
-
1977
- 1977-01-12 GB GB119177A patent/GB1499038A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5683570A (en) * | 1993-06-04 | 1997-11-04 | Dalhousie University | Gas detection method |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2283438A1 (en) | 1976-03-26 |
| NL7510323A (en) | 1976-03-04 |
| GB1505983A (en) | 1978-04-05 |
| DE2539001A1 (en) | 1976-03-18 |
| AU8441575A (en) | 1977-03-03 |
| GB1499038A (en) | 1978-01-25 |
| JPS5152892A (en) | 1976-05-10 |
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