JP2002122564A - Solid electrolyte type gas sensor - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To be mounted on a small solid electrolyte type gas sensor,
To provide a catalyst layer which can be manufactured by a simple manufacturing method and quality control and has a high catalytic ability. SOLUTION: An oxygen ion conductive solid electrolyte body 13;
The gas-permeable first electrode film 14 and the second electrode film 15 formed thereon, the gas-permeable carrier thin film 16 laminated on the first electrode film 14 to constitute a catalyst layer, and the gas-permeable oxidation catalyst thin film laminated thereon 17; The gas permeable oxidation catalyst thin film 17
Platinum formed by physical vapor deposition is the main component and its X
Assuming that the (111) plane detection peak intensity is a and the (200) plane detection peak intensity is b in the crystal structure analysis by the line diffraction method, the ratio (b / a) is 0.01 to 0.1.
As a result, the catalyst layer is formed by physical vapor deposition,
Moreover, since it has a unique platinum crystal structure, it can be formed by a simple manufacturing method and quality control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small solid electrolyte type gas sensor for detecting the concentration of carbon monoxide and hydrocarbons in the atmosphere, and more particularly, to a gas sensor mounted on this sensor.
The present invention relates to a catalyst layer which can be manufactured by a simple manufacturing method and quality control and has a high catalytic ability.

[0002]

2. Description of the Related Art Many types of solid electrolyte gas sensors have been proposed in the past as gas sensors sensitive to carbon monoxide and the like. FIGS. 9 (a) and 9 (b) show Japanese Unexamined Patent Publication No.
FIG. 9 shows a conventional solid electrolyte gas sensor described in Japanese Patent Publication No. 288593 and a catalyst layer used therein.
FIG. 9A is a cross-sectional view of a solid electrolyte gas sensor, and FIG.
FIG. 3 is a cross-sectional view of a catalyst layer.

[0003] The catalyst layer is composed of a porous layer 1 containing an oxidation catalyst.
This is a configuration in which particles of a noble metal-based or metal oxide-based oxidation catalyst 2 are dispersed in an alkali metal silicate-based or metal phosphate-based binder 3. On the other hand, the porous layer 1 containing the oxidation catalyst may be, in addition to the above-described constitution, supported by a ceramic fiber layer, a method of forming a film together with a film-forming powder by plasma spraying, a method of mixing and coating an enamel, The oxidation catalyst is contained and fixed by using a method of supporting on a sintered body.

In the solid electrolyte type gas sensor, the porous layer 1 containing the oxidation catalyst is formed on the surface of a ceramic porous body 4 having an average pore size of 1000 ° or less. This is a structure in which the first platinum electrode 6 formed on one side is laminated with a protrusion 7 interposed therebetween. Further, a second platinum electrode 8 is also formed on the other surface side of the oxygen ion conductor 5, and a ceramic porous body 10 is laminated with a projection 9 interposed therebetween, and heating means 11 and 12 are provided on both sides. .

Next, the crystal structure of the noble metal catalyst used for the oxidation catalyst 2, particularly platinum will be described. Platinum is also used for the platinum electrode films 6 and 8;
Patent No. 24943 discloses a sputtering method in which a platinum target is discharged in a vacuum argon atmosphere to form a film, and platinum particles are mixed with an organic solvent as described in JP-A-61-45962. It is generally formed by various methods such as a thick film printing method in which a paste is printed to form a film, dried and then fired. However, these conventional examples do not disclose any specific numbers relating to the crystal structure of platinum.

Further, a magazine “Surface Technology” Vol. 41, N
o4, 1990, page 338, describes the crystal structure of a platinum single crystal under the title of "Adsorption of atoms and molecules on the electrode surface and its behavior". The platinum single crystal described in the above document has a (111) plane but has no (200) plane or (220) plane, and no specific figures relating to these crystal planes are disclosed. Regarding the crystal structure of platinum, see the magazine “Surface” Vol. 28, No2, 1
Although it is also described in the title “NO adsorption characteristics and direct decomposition reaction” on page 87 of the 990 issue, only the (111) plane is mentioned, and the (200) plane and the (220) plane are not mentioned at all. The specific figures for these crystal planes are unknown.

Finally, the oxygen ion conductor 5 will be described. The oxygen ion conductor 5 is generally a stabilized zirconia body, and is used in a method of using a sintered plate in JP-A-58-124943, and in a method of using a sputtered film in JP-A-61-155751. It is described that the crystal orientations (111) and (220) are arranged in a specific direction. And these specific examples do not disclose any specific figures relating to the crystal structure of the stabilized zirconia body.

[0008]

SUMMARY OF THE INVENTION A conventional example of Japanese Patent Laid-Open No.
In the case of 288593, if the size of the sensor is large,
The catalyst layer can be formed by a simple manufacturing technique and a rough quality control, and a high catalytic ability can be obtained. However, since the smaller the sensor, the smaller the area of the platinum electrode and the shorter the gap distance with the other platinum electrodes, it is highly sophisticated and complicated to accurately stack the catalyst layer on the ceramic porous body 4 or the platinum electrode 6. There was a problem that a high quality control with high manufacturing technology and high precision was necessary. In addition, because of the configuration in which the particles of the oxidation catalyst are dispersed in the binder, the smaller the catalyst layer, the smaller the exposed area of the particles of the oxidation catalyst. The details will be described below.

The first problem will be described in the case of a catalyst layer using an inorganic adhesive using an alkali metal silicate-based binder. This inorganic adhesive material dries quickly and hardens when exposed to air, so it is poor in workability and is slightly inadvertent. (1) Part of the platinum electrode on the side where the accuracy is lost and the catalyst layer cannot be disposed Or (2) densification occurs,
(3) There is a problem that the sensor output becomes extremely small due to no fixation. This problem also occurs in a method of supporting a ceramic fiber layer and a method of forming a film together with a film forming powder by plasma spraying, in addition to the above-described inorganic adhesive. In order to prevent this problem, the formation of the catalyst layer required sophisticated and complicated manufacturing techniques and high-precision quality control.

The second problem will be described in the case where platinum is used as an oxidation catalyst. When the crystal structure of a conventional standard platinum powder is analyzed with an X-ray diffraction diffractometer, a large detection peak of the (111) plane is detected at 2θ = 40 °, and a medium detection peak of the (200) plane is obtained at 2θ = 46 °. A small detection peak on the (220) plane appears at 2θ = 67 °. And
Assuming that the detected peak intensity of the (111) plane is a and the detected peak intensity of the (200) plane is b, the ratio (b / a) is 0.5. Similarly, if the detected peak intensity on the (220) plane is c, the ratio (c / a) is 0.3. On the other hand, for platinum, it is said that among the above detection peaks, the (111) plane of the first peak particularly adsorbs gas such as oxygen most. Accordingly, as the number of (111) planes increases, that is, the second peak (220) detected peak intensity b
1) The surface detection peak intensity is smaller than a, that is, the ratio (b /
The smaller the value of a), the more carbon monoxide and oxygen are adsorbed, and a gas permeable oxidation catalyst thin film having excellent catalytic action can be obtained.

On the other hand, a platinum film formed by a conventional sputtering method has a problem that a sufficient catalytic ability cannot be obtained because the crystal structure of the platinum film varies in various ways depending on sputtering conditions and the (111) plane is small. is there. Also, platinum particles obtained by drying and calcining a conventional chloroplatinic acid aqueous solution as a starting material,
The crystal structure is the same as the standard platinum powder described above (111)
There is a problem that sufficient catalytic ability cannot be obtained due to the small number of surfaces.

The present invention solves the above-mentioned conventional problems, and has a structure for forming a catalyst layer used in a miniaturized solid electrolyte type gas sensor by a simple manufacturing method and quality control and having a high catalytic ability. The purpose is to provide.

[0013]

In order to solve the above-mentioned conventional problems, the catalyst layer of the solid electrolyte type gas sensor of the present invention is composed of a gas-permeable carrier thin film and a gas-permeable oxidation catalyst thin film laminated thereon. The gas permeable carrier thin film was made of a non-oxygen ion conductive ceramic thin film formed by physical vapor deposition. In addition, the breathable oxidation catalyst thin film,
Platinum formed by physical vapor deposition is the main component and its X
Assuming that the (111) plane detection peak intensity in the crystal structure analysis by the line diffraction method is a and the (200) plane detection peak intensity is b, the ratio (b / a) is 0.01 to 0.1.

Since the gas-permeable carrier thin film and gas-permeable oxidation catalyst thin film constituting the catalyst layer are formed and laminated by using a physical vapor deposition method, they are accurately arranged on the entire surface of the first electrode film and on the minute surroundings thereof. As a result, a catalyst layer having a porosity through which oxygen can pass satisfactorily and having a strong fixing strength can be obtained.

The gas-permeable oxidation catalyst thin film is mainly composed of platinum, and has a peak intensity (a) detected at the (111) plane and a peak intensity (a) at (200).
The ratio (b / a) of the surface detection peak intensities b is 0.01 to 0.1.
1, the (111) plane detection peak intensity a is (20)
0) It is larger than the surface detection peak intensity b. Therefore, a large amount of carbon monoxide and oxygen are adsorbed and oxidized to obtain a catalyst layer having excellent catalytic ability.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention can be embodied in the forms described in the claims.

According to a first aspect of the present invention, there is provided an oxygen ion conductive solid electrolyte, a gas-permeable first electrode film formed on a surface of the oxygen ion conductive solid electrolyte, and a second air electrode.
An electrode film, a gas-permeable carrier thin film laminated on the first electrode film, and a gas-permeable oxidation catalyst thin film laminated on the porous carrier thin film, wherein the gas-permeable carrier thin film is formed by a physical vapor deposition method. The gas-permeable oxidation catalyst thin film is mainly composed of platinum formed by a physical vapor deposition method, and the (111) plane in the crystal structure analysis by the X-ray diffraction method is formed of the non-oxygen ion conductive ceramic thin film formed by the method. Assuming that the detected peak intensity is a and the (200) plane detected peak intensity is b, the ratio (b / a) can be 0.01 to 0.1.

Since the gas-permeable carrier thin film and the gas-permeable oxidation catalyst thin film constituting the catalyst layer are formed and laminated by using the physical vapor deposition method, accurate arrangement on the entire surface of the first electrode film and its minute surroundings is achieved. A catalyst layer that simultaneously satisfies the porosity through which oxygen passes well and the strong fixing strength can be formed by a simple manufacturing method and quality control.

Further, the gas-permeable oxidation catalyst thin film is mainly composed of platinum, and has a peak intensity a (111) plane detection a and a (200)
The ratio (b / a) of the surface detection peak intensities b is 0.01 to 0.1.
1, the (111) plane detection peak intensity a is (20)
0) It is larger than the surface detection peak intensity b. Therefore, a large amount of carbon monoxide and oxygen are adsorbed and oxidized to obtain a catalyst layer having excellent catalytic ability.

According to the second aspect of the present invention, particularly, the gaseous oxidation catalyst thin film according to the first aspect contains platinum as a main component and has a (111) plane detection half width at half maximum in a crystal structure analysis by an X-ray diffraction method. It did not exceed 0.40 °. With this configuration, the crystallinity of the platinum (111) plane is increased, so that a solid electrolyte gas sensor having a catalyst layer with excellent responsiveness can be obtained.

According to a third aspect of the present invention, in particular, the half-width at the (200) plane detection peak in the crystal structure analysis of the gas-permeable oxidation catalyst thin film according to the first aspect which is mainly composed of platinum and which is composed of platinum as a main component by an X-ray diffraction method. It did not exceed 0.5 °. With this configuration, the crystallinity of the platinum (200) plane is increased, so that a solid electrolyte gas sensor having a catalyst layer having excellent responsiveness can be obtained.

According to a fourth aspect of the present invention, in particular, when the gas-permeable oxidation catalyst thin film according to the first aspect is mainly composed of platinum and its crystal structure is analyzed by an X-ray diffraction method, the detected peak intensity of the (220) plane is c. Then, the ratio (c / a) is 0.0
1 to 0.1. With this configuration, since the ratio (c / a) is small, the (111) plane detection peak intensity a becomes higher than the other surface (220) detection peak intensity c. Therefore, it is possible to obtain a solid electrolyte type gas sensor having a catalyst layer in which the detection sensitivity at a low concentration is enhanced by adsorbing more carbon monoxide.

According to a fifth aspect of the present invention, in particular, the gaseous oxidation catalyst thin film according to the first aspect contains platinum as a main component and has a (220) plane detection peak half width in a crystal structure analysis by an X-ray diffraction method. It did not exceed 0.60 °. Platinum (22
Since the crystallinity of the 0) plane increases, a solid electrolyte gas sensor having a highly responsive catalyst layer can be obtained.

According to a sixth aspect of the present invention, in particular, the air-permeable carrier thin film according to the first aspect is an alumina film in which a large number of crystals are arranged in the crystal orientation (113) plane. When the air-permeable carrier thin film is an alumina film in which many are arranged on the (113) plane, a porous and high-surface-area air-permeable carrier thin film is obtained, and the surface area of the air-permeable oxidation catalyst thin film laminated thereon is increased. A solid electrolyte type gas sensor having a catalyst layer with more excellent catalytic ability by adsorbing and oxidizing a large amount of carbon and oxygen can be obtained.

According to a seventh aspect of the present invention, in particular, the second electrode film of the first aspect is formed with an air-permeable coating of an alumina film arranged in a large number on the crystal orientation (113) plane. Since a gas-permeable alumina film was also formed on the second electrode film, the area of the first electrode film and the area of the second electrode film were substantially equal. Is almost zero in a fresh gas atmosphere in which no is contained. Since a sensor output corresponding to the concentration of carbon monoxide is obtained from the zero output as a starting point, a solid electrolyte type gas sensor that can easily detect the sensor output can be obtained.

According to an eighth aspect of the present invention, in particular, the first and second electrode films according to the first aspect are characterized in that platinum is a main component and the (111) plane detection peak in the crystal structure analysis by X-ray diffraction method. Assuming that the intensity is X and the (200) plane detection peak intensity is Y, the ratio (Y / X) is 0.01 to 0.1. Platinum is the main component, (11
1) Since the ratio (Y / X) of the plane detection peak intensity X to the (200) plane detection peak intensity Y is 0.01 to 0.1,
The (111) plane detection peak intensity X becomes larger than the (200) plane detection peak intensity Y. Therefore, it is possible to obtain a solid electrolyte type gas sensor having a platinum electrode film that emits a high sensor output by adsorbing and oxidizing a large amount of carbon monoxide and oxygen.

According to a ninth aspect of the present invention, in particular, the first and second electrode films according to the first aspect are characterized in that the first and second electrode films have a (111) plane detection peak half in a crystal structure analysis by an X-ray diffraction method using platinum as a main component. The value width did not exceed 0.40 °. With this configuration, the crystallinity of the platinum (111) plane is increased, so that a solid electrolyte type gas sensor having a platinum electrode film having excellent responsiveness can be obtained.

The invention described in claim 10 is particularly advantageous in claim 1.
In the crystal structure analysis by X-ray diffraction of the first and second electrode films described in (1) above, assuming that the detected peak intensity on the (220) plane is Z, the ratio (Z / X) is 0. 01 to 0.1. With this configuration, since the ratio (Z / X) is small in this configuration, (11)
1) The surface detection peak intensity X becomes higher than the other surface (220) detection peak intensity Z. Therefore, it is possible to obtain a solid electrolyte type gas sensor having a platinum electrode film having a higher detection sensitivity at a low concentration by adsorbing more carbon monoxide.

The invention described in claim 11 is particularly advantageous in claim 1.
Is a stabilized zirconia body containing 8 mol% of yttrium oxide and 92 mol% of zirconia oxide as main components, and (111) plane detection in crystal structure analysis by X-ray diffraction method. Assuming that the peak intensity is m and the (220) plane detection peak intensity is n, the ratio (n / m) does not exceed 0.5. With this configuration, since the ratio (n / m) is small, the (111) plane detection peak intensity m becomes larger than the other surface (220) detection peak intensity n. Therefore, a stabilized zirconia body having a rough surface having many irregularities is formed, and the platinum electrode film is satisfactorily adhered to the surface, so that a solid electrolyte gas sensor having a higher response speed can be obtained.

The invention described in claim 12 is particularly advantageous in claim 1.
The oxygen ion conductive solid electrolyte described in 1 was used as a stabilized zirconia body, and the half width at (111) plane detection peak in crystal structure analysis by X-ray diffraction method did not exceed 0.6 °. With this configuration, the stabilized zirconia body (11
1) Since the crystallinity of the surface is increased, oxygen ion conductivity is improved, and a solid electrolyte type gas sensor having a small internal resistance can be obtained.

The invention described in claim 13 is particularly advantageous in claim 1.
The oxygen ion conductive solid electrolyte described in 1 was used as a stabilized zirconia body, and the half width at (220) plane detection peak in crystal structure analysis by X-ray diffraction method did not exceed 0.7 °. With this configuration, the stabilized zirconia body (22
Since the crystallinity of the 0) plane is enhanced, a solid electrolyte type gas sensor having higher detection sensitivity can be obtained.

[0032]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

(Embodiment 1) FIG. 1 is a sectional view of a solid electrolyte gas sensor according to a first embodiment of the present invention. This solid electrolyte type gas sensor includes an oxygen ion conductive solid electrolyte body 13, a gas permeable first electrode film 14 and a gas permeable second electrode film 15 formed on the surface of the oxygen ion conductive solid electrolyte body 13, Air-permeable carrier thin film 1 laminated on electrode film 14
6 and at least a gas permeable oxidation catalyst thin film 17 laminated on a gas permeable carrier thin film 16.

The catalyst layer is composed of the gas permeable carrier thin film 16 and the gas permeable oxidation catalyst thin film 17 (hereinafter, this structure is referred to as a catalyst layer). The gas permeable carrier thin film 16 is made of a non-oxygen ion conductive ceramic thin film formed by physical vapor deposition. The gas-permeable oxidation catalyst thin film 17 is mainly composed of platinum formed by physical vapor deposition, and the peak intensity detected at the (111) plane in the crystal structure analysis by the X-ray diffraction method is defined as a, and the peak intensity detected at the (200) plane. b, the ratio (b
/ A) is from 0.01 to 0.1.

The carbon monoxide detection mechanism of the solid electrolyte type gas sensor will be described. On the side of the first electrode film 14 on which the catalyst layer is disposed, the carbon monoxide gas reacts with the oxygen gas by the catalytic action of the catalyst layer to become carbon dioxide gas and is consumed and lost. Because of the high concentration, the atmospheric concentration remains almost the same. On the other hand, on the other side of the second electrode film 15, the carbon monoxide gas and the oxygen gas react by the catalysis to form carbon dioxide gas, and the oxygen gas concentration on the surface decreases. Therefore, focusing on the oxygen concentration, the concentration on the first electrode film 14 side is higher than that on the second electrode film 15, and oxygen gas is transferred from the first electrode film 14 side to the second electrode film 15. Oxygen ions move in the ionic solid electrolyte body 13, and an electromotive force is generated by the oxygen movement. This electromotive force is the sensor output, and a value substantially proportional to the logarithmic value of the carbon monoxide gas concentration is obtained.

The product of the present invention was manufactured on a trial basis and its effect was confirmed. The oxygen ion conductive solid electrolyte 13 is a sputtered film of a stabilized zirconia body which is a solid solution of 8 mol% of yttrium oxide and 92 mol% of zirconium oxide, and is formed on a substrate 19 made of alumina. The first electrode film 14 and the second electrode film 15 are porous thin films of platinum formed by sputtering platinum, and are formed on the surface of the oxygen ion conductive solid electrolyte 13 described above. On top of the first electrode film 14, an alumina (one type of non-oxygen ion conductive ceramic) thin film is laminated by a sputtering method (one type of physical vapor deposition method) to form a gas permeable carrier thin film 16. did. Then, a gas-permeable oxidation catalyst thin film 17 made of platinum was laminated on the gas-permeable carrier thin film 16 by a sputtering method (a kind of physical vapor deposition method), and a catalyst layer was formed by both.

When the crystal structure of the platinum of the gas permeable oxidation catalyst thin film 17 was analyzed by an X-ray diffractometer, the following 3 was obtained.
Two detection peaks appeared. Appears at 2θ = 40 ° (11
1) Large detection peak on the surface (peak intensity 31465 cp)
s, half width 0.26). Appears at 2θ = 46 ° (20
0) Moderate detection peak (900 cp peak intensity)
s, half width 0.34). Appears at 2θ = 67 ° (22
0) Small detection peak on plane (peak intensity 900 cps,
0.38). Then, the ratio (b / a) between the (111) plane detection peak intensity a and the (200) plane detection peak intensity b
Is 0.03. Similarly, the ratio (c / a) to the (220) plane detection peak intensity c is 0.03.

Finally, a platinum lead wire (not shown) is bonded to the first electrode film 14 and the second electrode film 15 to complete the process.

As a comparative product, a gas permeable carrier thin film 16 of the same alumina as described above was separately prepared, and platinum was sputtered on the gas permeable carrier thin film 17 to form a gas permeable oxidation catalyst thin film 17 having a different crystal arrangement.

Further, as a conventional product, a kneaded product comprising 60 parts by weight of a water-containing uncured adhesive and 10 parts by weight of platinum particles is applied using a syringe and fired at 500 ° C. for 30 minutes to form a catalyst layer. .

The results of crystal structure analysis of the gas permeable carrier thin film 16 and the catalyst layer with an X-ray diffraction diffractometer are shown in Table 1.
Shown in

[0042]

[Table 1]

The product of the present invention is compared with a comparative product or a conventional product.
It can be seen that the (111) plane peak intensity is higher than the other surface peak intensity. The ratio (b / a) between the (111) plane detection peak intensity a and the (200) plane detection peak intensity b was calculated, and the magnitude was quantified. Since the comparative product is 0.20 and the conventional product is 0.54, the product of the present invention is 0.03, and the (111) plane peak intensity is larger than the other surface peak intensity. Shown small figures.

Inventive products and comparative products described in (Table 1),
A prototype of a solid electrolyte type gas sensor with a conventional catalyst layer was fabricated, and the productivity of the sensor, such as increased sensor output, yield of non-defective products, and formation time of the catalyst layer, was evaluated. The results are shown in (Table 2). These are the characteristics when ten solid electrolyte gas sensors were prototyped.

The output of the sensor was increased by holding the solid electrolyte type gas sensor in a 450 ° C. electric furnace, changing the gas from the air to 2000 ppm of carbon monoxide (air balance) gas and the air.
The atmosphere was sequentially changed, and the transient change of the electromotive force was measured. Then, the difference between the electromotive force between 2000 ppm of carbon monoxide and the atmosphere (hereinafter referred to as sensor output increase) is calculated.
The maximum value, the average value, and the minimum value in 0 pieces were represented.

The yield of non-defective products was set to 10 mv or more as a sensor output at which the detection of carbon monoxide was easy to control in a controlled manner, and the number of sensors satisfying the set value was divided by 10 prototypes and expressed as%.

The formation time of the catalyst layer was represented by the time required for one prototype. In the case of the product of the present invention and the comparative product, the sputtering time required for simultaneously forming the 10 gas-permeable carrier thin films 16 and the gas-permeable oxidation catalyst thin film 17 was divided by 10 and expressed as the time required for one prototype. . In the case of the conventional product, the time required for laminating the kneaded material on one side of the first electrode film at the time of trial production of one piece and the firing time required for firing 10 pieces of this laminated product by 10 times the time. , And the total value was expressed as the time required for one prototype. Thereafter, productivity evaluation such as increase in sensor output, yield of non-defective products, and formation time of the catalyst layer was performed by the above method unless otherwise specified.

[0048]

[Table 2]

It can be seen that the product of the present invention has a high sensor output as a whole and a good product yield of 100%, and can be dealt with by simple quality technology. In addition, since the catalyst layers are formed simultaneously by sputtering in 100 minutes in 100 minutes, the formation time is 10 minutes in terms of one layer. This indicates that a uniform quality catalyst layer can be formed by a simple manufacturing technique of 10 minutes using a sputtering method.

The comparative product has a problem that only a small sensor output can be obtained as a whole and that a sensor output having a small sensor output with a good yield of 80% is mixed, so that complicated quality control is required for selection.

In conventional products, when printing, the kneaded material is solidified by the print mask and a catalyst layer cannot be formed. Therefore, the kneaded material must be applied to a platinum electrode film using a syringe to form an oxidation catalyst film. For this reason, the catalyst layer is not accurately formed on the first electrode film, and is formed only on half of the first electrode film, or is partially formed on the second electrode film on the side that should not be formed. Only a small sensor was obtained. Therefore, the setting value of 10mv or more satisfies only 50%,
There was a problem that the prototype had to be inspected with high quality control. In addition, since the catalyst layer is formed by a syringe, it takes as long as 60 minutes to form the catalyst layer, and there is a problem that a complicated manufacturing technique is required.

FIG. 2 shows typical sensor output transient characteristics of the solid electrolyte type gas sensor. The evaluation was performed by holding the solid electrolyte type gas sensor in an electric furnace at 450 ° C. and measuring the transient change of the electromotive force when the atmosphere was sequentially changed from the atmosphere to 2000 ppm of carbon monoxide (air balance) and then to the atmosphere.

In the product of the present invention (ratio b / a: 0.03), a large electromotive force was obtained, and thus the sensitivity was improved. In addition, since the electromotive force is stabilized in a short time, there is an advantage that the response is quick. On the other hand, the comparative product (the ratio b / a is 0.20) and the conventional product (the ratio b / a is 0.54) have a small sensitivity due to a small electromotive force, and the response is slow because the value is not stable. There was.

Next, by changing the sputtering conditions of platinum, a breathable oxidation catalyst thin film 17 having a different crystal structure was produced on a trial basis. Then, the (111) plane detection peak intensity a is determined by X-ray diffraction.
And (200) plane detection peak intensity b were measured, and the ratio (b / a) of the detection peak intensity was calculated.

Table 3 shows the relationship between the ratio (b / a) of the detected peak intensity of the gas permeable oxidation catalyst thin film made of platinum and the increase in the sensor output.

[0056]

[Table 3]

The sensor output increases when the ratio (b / a) is 0.
At 01-0.1, large values were obtained. this is,
When the ratio (b / a) of the detected peak intensities of the (200) plane and the (111) plane is within this range, a gas-permeable oxidation catalyst thin film having excellent characteristics of adsorbing carbon monoxide and oxidizing it to carbon dioxide can be obtained. It seems to be done. On the other hand, when the ratio (b / a) is less than 0.01, only a small electromotive force is obtained, which is presumably because the (200) plane is small. In addition, the ratio (b
When / a) exceeds 0.1, only a small electromotive force is obtained,
This is probably because the (111) plane is small. Based on this, the following examinations show that the ratio (b / a) is 0.01 to 0.1.
The test was performed using the air permeable oxidation catalyst thin film No. 1.

The influence of the detection peak half width on the (111) and (200) planes of the gas-permeable oxidation catalyst thin film on the sensor characteristics was clarified by using various gas-permeable oxidation catalyst thin films having different crystal structures. As a result, the half width of the (111) plane was changed to the response characteristic from the atmosphere to 2000 ppm of carbon monoxide, and (2)
The half width of the (00) plane was found to affect the response characteristics to the atmosphere from 2000 ppm of carbon monoxide.

(Example 2) In Example 2, the half width of the platinum (111) plane of the gas permeable oxidation catalyst thin film 17 made of platinum was examined. (Table 4) shows (1) of the gas permeable oxidation catalyst thin film.
11) Surface half width and 2000pp carbon monoxide from the atmosphere
90% response time to m.

[0060]

[Table 4]

The 90% response time greatly changes at a half value width of 0.4 °, and a quick response was obtained when the half width was less than 0.4 °. This is because, when the half-value width is less than 0.4 °, the crystallinity is excellent, so that a gas-permeable oxidation catalyst thin film having many (111) planes having excellent characteristics of adsorbing carbon monoxide most and oxidizing to carbon dioxide is obtained. That is because On the other hand, if the half width exceeds 0.4 °, the crystallinity is poor, so that a gas-permeable oxidation catalyst thin film having a (111) plane having poor adsorption of carbon monoxide and poor oxidation to carbon dioxide can be obtained. is there.

In the above prototype, a large sensor output was obtained as a whole and the yield of non-defective products was 100%. In addition, a uniform quality catalyst layer could be formed by a simple manufacturing technique of 10 minutes using a sputtering method.

Example 3 In Example 3, the half width of the platinum (200) plane of the gas permeable oxidation catalyst thin film 17 made of platinum was examined.

Table 5 shows the relationship between the half width of the (200) plane and the 90% response time from 2000 ppm of carbon monoxide to the atmosphere.

[0065]

[Table 5]

The 90% response time greatly changed at a half width of 0.5 °, and when the half width was less than 0.5 °, a quick response was obtained. This is because, when the half width is less than 0.5 °, the crystallinity is excellent, so that a gas-permeable oxidation catalyst thin film having many (200) planes, which is particularly excellent in oxygen adsorption characteristics, can be obtained. On the other hand, if the half width exceeds 0.5 °, the crystallinity is poor, so that a gas-permeable oxidation catalyst thin film having many (200) planes having poor oxygen adsorption characteristics can be obtained.

Incidentally, the above-mentioned prototype produced a large sensor output as a whole, yielded a non-defective product of 100%, and could be handled with simple quality technology. In addition, a uniform quality catalyst layer could be formed by a simple manufacturing technique of 10 minutes using a sputtering method.

Example 4 In Example 4, the detection peak intensity c of the platinum (220) plane of the gas permeable oxidation catalyst thin film 17 made of platinum was examined.

The gas permeable oxidation catalyst thin film also has a (220) plane. Therefore, the influence of the (220) plane detection peak intensity c on the sensor characteristics was clarified. Evaluation conditions for elucidation
As described above, but 200 ppm of carbon monoxide from the atmosphere
(Air balance) Gas and measuring the transient change of the electromotive force by changing the atmosphere in order to the atmosphere. As a result, it was found that the coexistence of the (220) plane improved the low concentration detection characteristics of carbon monoxide.

Table 6 shows (11) of the gas permeable oxidation catalyst thin film.
1) The relationship between the ratio (c / a) of the surface detection peak intensity a to the (220) surface detection peak intensity c and the sensor output increase at 200 ppm of carbon monoxide.

[0071]

[Table 6]

The sensor output increases when the ratio (c / a) is 0.
At 01-0.1, large values were obtained. this is,
When the ratio (c / a) of the detected peak intensities of the (220) plane and the (111) plane is within this range, a platinum electrode film having excellent characteristics of adsorbing low-concentration carbon monoxide and oxidizing it to carbon dioxide can be obtained. It seems to be obtained. On the other hand, when the ratio (c / a) is less than 0.01, only a small electromotive force is obtained, which is presumably because the (200) plane is small. In addition, the ratio (c
When / a) exceeds 0.1, only a small electromotive force is obtained,
This is probably because the (111) plane is small. From this, the following examination is made that the ratio (c / a) is 0.01 to 0.1.
The test was performed using a gas permeable oxidation catalyst thin film.

The above prototype was manufactured using carbon monoxide 2000
Even in ppm, a large sensor output was obtained and the yield of non-defective products was 100%, which could be handled with simple quality technology. Also,
A catalyst layer of uniform quality could be formed by a simple manufacturing technique of 10 minutes using a sputtering method.

Example 5 In Example 5, the half width of the platinum (220) plane of the gas permeable oxidation catalyst thin film 17 made of platinum was examined.

Table 7 shows (22) of the gas permeable oxidation catalyst thin film.
The relationship between the half width of the 0) plane and the 90% response time from the atmosphere to 200 ppm of carbon monoxide.

[0076]

[Table 7]

The 90% response time greatly changed at a half width of 0.6 °, and when the half width was less than 0.6 °, a quick response was obtained. This is because when the half width is less than 0.6 °, a gas-permeable oxidation catalyst thin film having many (220) planes having excellent crystallinity can be obtained. On the other hand, when the half width exceeds 0.4 °, a (200) plane air-permeable oxidation catalyst thin film having poor crystallinity can be obtained.

Note that the prototype is a carbon monoxide 2000
Even in ppm, a large sensor output was obtained and the yield of non-defective products was 100%, which could be handled with simple quality technology. Also,
A catalyst layer of uniform quality could be formed by a simple manufacturing technique of 10 minutes using a sputtering method.

Example 6 In Example 6, the material used for the porous carrier thin film was examined.

When the crystal structure of the alumina was analyzed with an X-ray diffractometer, the peak of the (113) plane at 2θ = 35 °, the peak of the (116) plane at 2θ = 44 °, and 2θ = 58
The peak of the (104) plane appears at °. Therefore, by adjusting the sputtering conditions, a porous carrier thin film made of alumina is arranged on the (113) plane where the peak height of the (113) plane is twice the peak height of the other plane. A porous carrier thin film made of alumina having almost the same regular arrangement was produced. In addition, a porous carrier thin film made of silica alumina having a normal arrangement and a porous carrier thin film made of silica having a normal arrangement were also experimentally produced.

Table 8 shows the relationship between the material used for the porous carrier thin film and the sensor output increase of 2,000 ppm of carbon monoxide.

[0082]

[Table 8]

It can be seen that the porous carrier thin film of the alumina film of the present invention, which is arranged in large numbers on the (113) plane, has a large value for increasing the sensor output. This is because a porous, high-surface-area porous carrier thin film is obtained, and the surface area of the gas-permeable oxidation catalyst thin film laminated on the porous support thin film is also increased. This is because a solid electrolyte type gas sensor having a catalyst layer was obtained.

(Embodiment 7) In the embodiment 7, the second electrode film 15
In addition, the effect of forming an air-permeable coating 18 of an alumina film, which was arranged in a large number on the crystal orientation (113) plane, was confirmed.

Table 9 shows the relationship between the presence or absence of this thin film on the second electrode film, the output in a fresh gas atmosphere containing no carbon monoxide, and the sensor output of 2000 ppm of carbon monoxide.

[0086]

[Table 9]

In the product of the present invention in which the gas-permeable alumina film is formed on the second electrode film, the areas of the first electrode film and the second electrode film are substantially equal, so that the oxygen gas adsorption capacities of both electrode films are substantially equal. As a result, the output in a fresh gas atmosphere containing no carbon monoxide becomes substantially zero. Therefore, a sensor output corresponding to the concentration of carbon monoxide is obtained from the zero output as a starting point, so that it is possible to obtain a solid electrolyte type gas sensor in which the sensor output can be easily detected.

(Eighth Embodiment) In the eighth embodiment, the first electrode film 14
The crystal structure of (111) and (200) planes of platinum used for the second electrode film 15 (hereinafter referred to as a platinum electrode film) was examined.

By changing the sputtering conditions, platinum electrode films having different crystal structures were experimentally manufactured. Then, the (111) plane detected peak intensity X and the (200) plane detected peak intensity Y were measured by the X-ray diffraction method, and the ratio (Y / X) of the detected peak intensities was calculated. This calculation method is the same as the method described in the first embodiment.

The solid electrolyte type gas sensor using the platinum electrode film was held in an electric furnace at 450 ° C., and the atmosphere was sequentially changed from the atmosphere to 2000 ppm of carbon monoxide (air balance) gas and then to the atmosphere. Power transients were measured. Then, the difference between the electromotive force between 2000 ppm of carbon monoxide and the atmosphere (hereinafter referred to as an increase in sensor output) was calculated.

FIG. 3 shows the relationship between the ratio (Y / X) of the detected peak intensity of the platinum electrode film and the increase in the sensor output. As for the increase in the sensor output, a large value was obtained when the ratio (Y / X) was 0.01 to 0.1. This is the (200) plane and (1)
11) It is considered that when the ratio (Y / X) of the detected peak intensities of the surface is in this range, a platinum electrode film having excellent characteristics of adsorbing carbon monoxide and oxidizing it to carbon dioxide can be obtained.
On the other hand, when the ratio (Y / X) is less than 0.01, only a small electromotive force is obtained, which is presumably because the (200) plane is small. When the ratio (Y / X) exceeds 0.1, only a small electromotive force is obtained, which is considered to be due to the small number of (111) planes.

Thus, except for Example 8, the examination was performed using a platinum electrode film having a ratio (Y / X) of 0.01 to 0.1.

The (111) plane and the (20)
The effect of the detection peak half width on the 0) plane on the sensor characteristics was clarified using various platinum electrode films having different crystal structures. As a result, the half width of the (111) plane has an effect on the response characteristics from the atmosphere to 2000 ppm of carbon monoxide, and the half width of the (200) plane has an effect on the response characteristics from 2000 ppm of carbon monoxide to the air. There was found.

(Embodiment 9) In the ninth embodiment, the first electrode film 14
Further, the half-value width of the (111) plane of platinum used for the second electrode film 15 (referred to as a platinum electrode film) was examined.

FIG. 4 shows the relationship between the half width of the (111) plane of the platinum electrode film and the 90% response time from the air to 2000 ppm of carbon monoxide. The 90% response time has a half width of 0.
The response greatly changed around 4 °, and a quick response was obtained when the angle was less than 0.4 °. This is because, when the half width is less than 0.4 °, the crystallinity is excellent, so that a platinum electrode film having many (111) planes having excellent characteristics of adsorbing carbon monoxide most and oxidizing to carbon dioxide is obtained. It is. On the other hand, if the half width exceeds 0.4 °, the crystallinity is poor, so that a platinum electrode film having a (111) plane with poor carbon monoxide adsorption and carbon dioxide oxidizability can be obtained.

Example 10 In Example 10, the crystal structure of the platinum used for the first electrode film 14 and the second electrode film 15 (referred to as a platinum electrode film) with respect to the (111) plane and the (220) plane was examined. did.

The platinum electrode film also has a (220) plane. Then, the influence of the (220) plane detection peak intensity Z on the sensor characteristics was clarified. The elucidation method is the same as the method described in the above-mentioned Example 4, except that 200 ppm of carbon monoxide is removed from the atmosphere.
(Air balance) The transient change of the electromotive force was measured by sequentially changing the atmosphere in the gas and then in the atmosphere.
As a result, it was found that the coexistence of the (220) plane improved the low concentration detection characteristics of carbon monoxide.

FIG. 5 shows the ratio (Z) between the (111) plane detected peak intensity X and the (220) plane detected peak intensity Z of the platinum electrode film.
/ X) and the increase in sensor output. The increase in the sensor output shows different behavior between 2000 ppm and 200 ppm of carbon monoxide. The change in electromotive force of 200 ppm of carbon monoxide has a large value when the ratio (Z / X) is 0.01 to 0.1. Obtained. This is because, when the ratio (Z / X) of the detected peak intensities of the (220) plane and the (111) plane is in this range, platinum that has excellent characteristics of adsorbing low-concentration carbon monoxide and oxidizing it to carbon dioxide is excellent. This is probably because an electrode film was obtained.
On the other hand, when the ratio (Z / X) is less than 0.01, only a small electromotive force is obtained, which is presumably because the (200) plane is small. When the ratio (Z / X) exceeds 0.1, only a small electromotive force is obtained, which is presumably due to the small number of (111) planes. From this, the following examination is based on the ratio (Z /
X) was performed using a platinum electrode film having a value of 0.01 to 0.1.

Example 11 In Example 11, the crystal structure of the stabilized zirconia used in the oxygen ion conductive solid electrolyte 13, particularly, the crystal structure related to the (111) plane and the (220) plane was examined.

A component in which a stabilized zirconia body as the oxygen ion conductive solid electrolyte body 13 was laminated on a substrate 19 containing alumina as a main component by a sputtering method was experimentally manufactured. The stabilized zirconia body is 8 mol% of yttrium oxide.
And a solid solution containing 92 mol% of zirconium oxide. This thin film is formed on the substrate 19 by a sputtering method and then heat-treated at 1000 ° C. for several hours. Stabilized zirconia body 6
Analysis of crystal structure by X-ray diffraction diffractometer gives 2θ = 30 °
A large detection peak on the (111) plane (peak intensity 293)
0 cps, half width 0.23) becomes 2θ = 50 ° (22
0) Medium detection peak (peak intensity 959 cp)
s, half width 0.46) appears. Then, assuming that the detected peak intensity of the (111) plane is m and the detected peak intensity of the (220) plane is n, the ratio (n / m) was 0.33.

As a comparative example, a component using a sintered plate of a stabilized zirconia body was also trial manufactured. The results of the crystal structure analysis are shown in (Table 10).

[0102]

[Table 10]

The solid electrolyte type gas sensor of this configuration is
Keep in an electric furnace at 0 ° C and 2,000 pp of carbon monoxide from the atmosphere
The transient change in the electromotive force when the atmosphere (atmospheric balance) gas and then the atmosphere were sequentially changed was measured. As a result, the product of the present invention (the ratio n / m was 0.33) had the advantage that the electromotive force was stable in a short time and the response time was short. This is presumably because the stabilized zirconia body having this crystal structure becomes a porous film having many irregularities, thereby making the platinum electrode film adhere well, and the adsorption and desorption of oxygen molecules proceeds smoothly. On the other hand, the comparative product (the ratio n / m was 0.58) also had a disadvantage that the response was slow because the electromotive force was not stable. This is presumably because the baked zirconia body is a dense fired body with few irregularities, and thus has insufficient adhesion with the platinum electrode film, and the adsorption and desorption of oxygen molecules does not proceed smoothly. The substrate 19
A platinum heater film is stacked on top of this, and an insulating film containing alumina as a main component is further stacked on the platinum heater film by sputtering, and a stabilized zirconia body 6 is formed on the insulating film by sputtering. As a result of confirming the effect of a prototype (reference product) formed by the above method, characteristics almost equivalent to those of the product of the present invention were obtained.

Since it was found that the ratio (n / m) of the detected peak intensity of the stabilized zirconia body was deeply involved in the response, the relationship between the ratio (n / m) and the response was measured.

FIG. 6 shows that the sputtering conditions are changed to change the crystal structure of the stabilized zirconia body, and the ratio (n / m) of the peak intensity m of the (111) plane detection peak to the peak intensity n of the (220) plane detection, It is the result of having measured the relationship of the response time.
The evaluation conditions are as described above. The 90% response time largely changed at a ratio (n / m) of 0.5, and when the ratio was less than 0.5, a short response time was obtained. This is the ratio (n /
If the value of m) is less than 0.5, the crystal structure of the stabilized zirconia body becomes porous with many irregularities, thereby making the platinum electrode film adhere well, and the absorption and desorption of oxygen molecules proceed smoothly. . On the other hand, when the ratio (n / m) is 0.5 or more, the crystal structure of the stabilized zirconia body becomes dense with few irregularities, the adhesion to the platinum electrode film is reduced, and the adsorption and desorption of oxygen molecules is reduced. Probably because it does not proceed smoothly. Therefore, the first embodiment
Examinations other than 1 were performed using stabilized zirconia bodies having a ratio (n / m) of less than 0.5.

Next, the crystallinity of the stabilized zirconia body is changed by changing the sputtering conditions and the subsequent heat treatment conditions, and the influence of the detected peak half width on the (111) plane and the (220) plane on the sensor characteristics. Was clarified. As a result, it was found that the (111) plane detection peak half width is deeply related to the resistance of the stabilized zirconia body and the (220) plane detection peak half width is deeply related to the sensor output increase.

Example 12 In Example 12, the half width of the (111) plane of the stabilized zirconia used for the oxygen ion conductive solid electrolyte 13 was examined.

FIG. 7 shows the relationship between the half width at the peak of the (111) plane detection and the resistance of the stabilized zirconia body. The resistance of the stabilized zirconia body greatly changed at a half width of 0.6 °, and when the half width was less than 0.6 °, a small resistance was obtained. This is because when the half width is less than 0.6 °, the crystallinity is excellent (1).
11) Since a stabilized zirconia body having many faces can be obtained, oxygen ion conductivity is improved and resistance is reduced. On the other hand, when the half width is 0.6 ° or more, a stabilized zirconia body having many (111) planes having poor crystallinity is obtained, and thus the resistance is increased.

Example 13 In Example 13, the half value width of the (220) plane of the stabilized zirconia body used for the oxygen ion conductive solid electrolyte body 13 was examined.

FIG. 8 shows the relationship between the (220) plane detection peak half width and the increase in sensor output. The increase in the sensor output largely changed at a half width of 0.7 °, and when the half width was less than 0.7 °, an increase in the sensor output was obtained. This means that the half width is 0.7
When the angle is less than °, a stabilized zirconia body having many (220) planes having excellent crystallinity can be obtained, so that the sensor output can be increased. On the other hand, when the half-value width is 0.7 ° or more, a stabilized zirconia body having many (220) planes having poor crystallinity can be obtained, and the increase in sensor output is small.

Here, the peak detection half-value widths of the (111) plane, (200) plane and (220) plane of the platinum electrode film,
The peak width at half maximum of the (111) plane and the (220) plane of the stabilized zirconia body will be described. This is the X-ray angle (2θ) corresponding to half the detected peak intensity when the crystal structure is analyzed by the X-ray diffraction method.

[0112]

As apparent from the above description, the solid electrolyte gas sensor of the present invention has the following effects.

The gas permeable carrier thin film and gas permeable oxidation catalyst thin film constituting the catalyst layer are formed and laminated by using the physical vapor deposition method, so that they are accurately arranged on the entire surface of the first electrode film and on the minute periphery thereof. You. Therefore, a catalyst layer that simultaneously satisfies the porosity through which oxygen can pass well and the strong fixing strength can be manufactured by a simple manufacturing method and quality control.

The gas-permeable oxidation catalyst thin film is mainly composed of platinum and has a (111) plane, a (200) plane and a (220) plane.
Since it has a crystal structure in which the ratio of the plane and the half width are unique, a large amount of carbon monoxide and oxygen are adsorbed and oxidized to obtain a catalyst layer having excellent catalytic ability.

[Brief description of the drawings]

FIG. 1 is a sectional view of a solid electrolyte gas sensor according to a first embodiment of the present invention.

FIG. 2 is an effect characteristic diagram showing a transient characteristic of a sensor output of a solid electrolyte gas sensor according to an eighth embodiment of the present invention.

FIG. 3 is an effect characteristic diagram showing a relationship between a peak ratio (Y / X) of a platinum electrode film and an increase in sensor output in a solid oxide gas sensor according to Embodiment 9 of the present invention.

FIG. 4 is an effect characteristic diagram showing a relationship between a (111) plane half width of a platinum electrode film and a 90% response time of a solid oxide gas sensor according to Example 10 of the present invention.

FIG. 5 is an effect characteristic diagram showing a relationship between a peak ratio (Z / X) of a platinum electrode film of a solid electrolyte gas sensor and an increase in sensor output in Embodiment 11 of the present invention.

FIG. 6 shows the peak ratio (n / m) of stabilized zirconia of the solid electrolyte gas sensor and Example 9 in Example 12 of the present invention.
Effect characteristic diagram showing the relationship of 0% response time

FIG. 7 is an effect characteristic diagram showing a relationship between a stabilized zirconia (111) plane half-width and a stabilized zirconia resistance of a solid oxide gas sensor according to Example 12 of the present invention.

FIG. 8 is an effect characteristic diagram showing a relationship between a stabilized zirconia (220) plane half width and an increase in sensor output of a solid oxide gas sensor according to Embodiment 13 of the present invention.

9A is a sectional view of a conventional solid electrolyte gas sensor, and FIG. 9B is a sectional view of a catalyst layer of the sensor.

[Explanation of symbols]

 13 Oxygen ion conductive solid electrolyte body 14 First electrode film 15 Second electrode film 16 Gas permeable carrier thin film 17 Gas permeable oxidation catalyst thin film 18 Gas permeable coating

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Katsuhiko Uno 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Takashi Niwa 1006 Kadoma Kadoma, Kadoma City Osaka Pref. 72) Inventor Takahiro Umeda 1006 Kadoma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. GA14 KA08 LA20 MA05 RA03 2G004 BB04 BD04 BE12 BE22 BF02 BF05 BF07 BF08 BM04

Claims (13)

[Claims] 1. An oxygen ion conductive solid electrolyte, a gas permeable first electrode film and a second electrode film formed on a surface of the oxygen ion conductive solid electrolyte, and a stack of the oxygen ion conductive solid electrolyte and the first electrode film And a gas-permeable carrier thin film laminated on the gas-permeable carrier thin film, wherein the gas-permeable carrier thin film is a non-oxygen ion conductive ceramic thin film formed by physical vapor deposition. Wherein the gas-permeable oxidation catalyst thin film is composed mainly of platinum formed by physical vapor deposition, and the peak intensity detected at the (111) plane in the crystal structure analysis by X-ray diffraction method is defined as a.
A solid electrolyte gas sensor in which the ratio (b / a) is 0.01 to 0.1, where b is the surface detection peak intensity. 2. Platinum, which is a main component of the gas permeable oxidation catalyst thin film, is (111) in a crystal structure analysis by an X-ray diffraction method.
The solid electrolyte type gas sensor according to claim 1, wherein the half width at half maximum of the surface detection does not exceed 0.40 °. 3. Platinum, which is a main component of the gas-permeable oxidation catalyst thin film, is analyzed by a crystal structure analysis by X-ray diffraction method (200).
The solid electrolyte type gas sensor according to claim 1, wherein a half width at a surface detection peak does not exceed 0.5 °. 4. Platinum, which is a main component of the gas permeable oxidation catalyst thin film, is analyzed by a crystal structure analysis by X-ray diffraction (220).
Assuming that the detected peak intensity of the surface is c, the ratio (c / a)
The solid electrolyte type gas sensor according to claim 1, wherein is 0.01 to 0.1. 5. Platinum, which is a main component of the gas permeable oxidation catalyst thin film, is analyzed by crystal structure analysis by X-ray diffraction (220).
The solid electrolyte type gas sensor according to claim 4, wherein the half width at half maximum of the surface detection does not exceed 0.60 °. 6. The air-permeable carrier thin film has a crystal orientation (113).
2. The solid electrolyte type gas sensor according to claim 1, wherein the gas sensor is an alumina film arranged in large numbers on a surface. 7. The solid electrolyte type gas sensor according to claim 1, wherein a gas permeable film, which is an alumina film arranged in a large number in the crystal orientation (113) plane, is formed on the second electrode film. 8. The first and second electrode films are mainly composed of platinum, and the first and second electrode films have the same structure as that of (1) in the crystal structure analysis by X-ray diffraction method.
11) Assuming that the plane detection peak intensity is X and the (200) plane detection peak intensity is Y, the ratio (Y / X) is 0.01 to
The solid electrolyte type gas sensor according to claim 1, wherein the value is 0.1. 9. Platinum, which is a main component of the first and second electrode films, is analyzed by X-ray diffractometry for crystal structure analysis (11
9. The solid electrolyte gas sensor according to claim 8, wherein 1) the half width of the surface detection peak does not exceed 0.40 °. 10. Platinum, which is a main component of the first and second electrode films, is analyzed by a crystal structure analysis using an X-ray diffraction method.
Assuming that the detected peak intensity of the 0) plane is Z, the ratio (Z /
The solid electrolyte type gas sensor according to claim 8, wherein X) is 0.01 to 0.1. 11. The oxygen ion conductive solid electrolyte comprises 8 mol% of yttrium oxide and 92 mol% of zirconia oxide.
Is a stabilized zirconia body having a main component, and in the crystal structure analysis by the X-ray diffraction method, the detected peak intensity at the (111) plane is m, and the detected peak intensity at the (220) plane is n.
The solid electrolyte type gas sensor according to claim 1, wherein the ratio (n / m) does not exceed 0.5. 12. The solid electrolyte type gas sensor according to claim 11, wherein the peak half-value width of the (111) plane detected in the crystal structure analysis of the stabilized zirconia body by X-ray diffraction does not exceed 0.6 °. 13. The solid electrolyte type gas sensor according to claim 11, wherein the (220) plane detection peak half width of the stabilized zirconia body does not exceed 0.7 ° in a crystal structure analysis by an X-ray diffraction method.