WO2005103676A1

WO2005103676A1 - Method for visualizing hydrogen distribution, system for visualizing hydrogen distribution, emission reagent for visualizing hydrogen distribution, method for detecting hydrogen and reagent for detecting hydrogen

Info

Publication number: WO2005103676A1
Application number: PCT/JP2005/008260
Authority: WO
Inventors: Hideyuki Saitoh
Original assignee: Japan Science And Technology Agency
Priority date: 2004-04-23
Filing date: 2005-04-22
Publication date: 2005-11-03
Also published as: JPWO2005103676A1

Abstract

A method for visualizing hydrogen distribution in a material, e.g. a metal, using chemiluminescence. Lucigenin is employed as an emission reagent. Chemiluminescence takes place when lucigenin reacts on hydrogen. Hydrogen distribution is visualized by measuring the position and intensity of emission using a CCD camera, or the like.

Description

Hydrogen distribution visualization method, hydrogen distribution visualization system, luminescence reagent for visualizing hydrogen distribution, hydrogen detection method and hydrogen detection reagent

Technical field

The present invention relates to a method for visualizing hydrogen distribution, a system for visualizing hydrogen distribution, a luminescent reagent for visualizing hydrogen distribution, a method for detecting hydrogen, and a reagent for detecting hydrogen.

In particular, it is suitable for use in visualizing the distribution of hydrogen in metals and other materials.

Background art

Visually observing and observing the distribution of hydrogen in a metal is a very effective means of investigating the correlation between metallographic structure and hydrogen behavior. Therefore, it is thought that the development of hydrogen visualization technology will greatly contribute to elucidation of the mechanism of hydrogen embrittlement, its prevention, and improvement of the performance of hydrogen storage alloys. Here, hydrogen embrittlement is embrittlement caused by hydrogen dissolved in a metal, and appears remarkably even when the concentration of hydrogen in the metal is extremely small. Hydrogen storage alloys are materials that reversibly absorb and release hydrogen, are used for storing and transporting hydrogen, and are key materials that use hydrogen energy.

Conventionally, methods of observing hydrogen distribution on the surface of a metal material can be roughly classified into a method using tritium, which is a radioactive isotope of hydrogen, and a method using non-radioactive isotope of hydrogen. The former method includes an autoradiographic method and a radioluminographic method. In the autoradiography method, a photographic emulsion is placed on a sample to which tritium has been added, and the distribution of tritium is observed by the photographic blackening of beta rays emitted by tritium. It is a method. Radioluminography is a method in which a sample to which tritium is added is placed on an imaging plate and the intensity distribution of the tritium emission line is recorded. The latter method includes a silver decoration method and a hydrogen microprinting method. In the silver decoration method, when a sample in which hydrogen is added to an aqueous solution of potassium potassium cyanide is immersed, silver ions react with hydrogen atoms on the sample surface and precipitate as silver atoms, and the distribution of silver atoms is observed. This is a method to determine the position of hydrogen. In the hydrogen microphone print method, photographic emulsion grains are placed on a sample, and silver bromide (AgBr) particles in the emulsion are reduced by hydrogen moving from inside the sample into silver particles. This is a method of observing particles and examining the hydrogen distribution.

However, the above-described autoradiographic method is difficult to perform quantitative analysis, the radioluminographic method has poor resolution, and the silver decoration method and the hydrogen microprint method are both quantitative analyzes of hydrogen release behavior. There was a problem that it was impossible to perform real-time observation, and both were pros and cons.

Therefore, the problem to be solved by the present invention is that hydrogen distribution in various materials including metals can be easily visualized, and quantitative analysis of hydrogen リアルタイム real-time observation of hydrogen distribution with high resolution It is an object of the present invention to provide a method and system for visualizing hydrogen distribution and a luminescent reagent used for them.

Another problem to be solved by the present invention is that, more generally, the distribution of hydrogen in various materials such as metals can be easily visualized, and quantitative analysis of hydrogen and real-time observation of hydrogen distribution can be performed. An object of the present invention is to provide a method and a reagent for detecting hydrogen that can be performed at a high resolution. Disclosure of the invention The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, chemiluminescence (chemiluminescence), which is a phenomenon in which a molecule that is excited by a chemical reaction and enters an excited state emits light when returning to a ground state. (Chemi lumines cence)), it was found that hydrogen can be detected. More specifically, lucigenin (N, N-dimethyl 9,9-diclidinium nitrate)

When lucigen was used as a luminescent reagent, it was found that this lucigenin emitted light due to hydrogen. By using this chemiluminescence, the distribution of hydrogen in a material such as a metal can be easily visualized. Also, by measuring the position and intensity of this light emission using a CCD camera or the like, real-time measurement and remote measurement by remote control are possible.

Taro Hayashi: Photochemistry and its applications, Takao Kan, Masao Koizumi, Ikuzo Tanaka, edited by Kagaku Doujin, (1965) pp. 127-128, describes the chemiluminescence mechanism of lucigenin. There are many unclear points, and there is no mention that chemiluminescence is caused by reaction with hydrogen.

The present invention has been devised based on the above study.

That is, to solve the above problems, the first invention is: This is a method for visualizing hydrogen distribution, characterized by visualizing hydrogen distribution in a material using chemiluminescence.

Visualization of the hydrogen distribution is typically performed by obtaining the distribution of the position and intensity of the luminescence by detecting the chemiluminescence using a photodetector. As the light detection device, for example, various types of devices such as a CCD camera, a scintillation detector, a photodiode array, and a photomultiplier tube can be used. Use the best one according to the situation. When a CCD camera is used as the light detection device, the hydrogen distribution can be visualized as a distribution of the position and intensity of the light emission by imaging the chemiluminescence using the CCD camera.

Visualization of the hydrogen distribution is performed by bringing a luminescent reagent into contact with the material whose hydrogen distribution is to be visualized. At this time, chemiluminescence is caused according to the distribution of hydrogen in the material. Specifically, the contact of the luminescent reagent with the material whose hydrogen distribution is to be visualized is performed by bringing a solution containing the luminescent reagent or a gel impregnated with the solution into contact with the material.

After the solution containing the luminescent reagent is prepared, the luminescence of the solution itself may occur. Therefore, from the viewpoint of suppressing this background luminescence and clearly distinguishing the luminescence by the reaction between the chemical reagent and hydrogen. After the luminescence intensity from the solution containing the luminescent reagent has passed its peak, the solution is brought into contact with the material whose hydrogen distribution is to be visualized, and the chemical reagent in the solution is brought into contact with the material. As a luminescent reagent, for example, lucigenin is used. As a solvent for the solution containing lucigenin, preferably, for example, an aqueous solution of an alkali such as NaOH or KOH is used. What kind of material is used to visualize the hydrogen distribution Specific examples include various metals or alloys such as steel materials that may cause hydrogen embrittlement, hydrogen storage alloys, and separators for fuel cells. is there.

The second invention is

This is a hydrogen distribution visualization system characterized by visualizing the hydrogen distribution in a material using chemiluminescence.

The hydrogen distribution visualization system typically includes a contact body containing a luminescent reagent and a photodetector, and the luminescent reagent of the contact body is brought into contact with a material whose hydrogen distribution is to be visualized. The chemiluminescence caused by the light is detected using a photodetector. Then, by detecting the chemiluminescence using a photodetector, the hydrogen distribution is visualized as the distribution of the position and intensity of the luminescence. The contact body and the photodetector may be disposed integrally or may be disposed separately. The contact body typically has a solution containing a luminescent reagent or a gel impregnated with the luminescent reagent. These solutions or gels are usually housed in a transparent container or a container with a transparent light extraction area and an opaque (black) other part, and are then attached to a material whose hydrogen distribution is to be visualized.

In the second invention, what has been said in relation to the first invention holds unless the nature of the second invention is violated.

The third invention is

This is a luminescent reagent for visualizing hydrogen distribution composed of lucigenin.

The fourth invention is

This is a hydrogen detection method characterized by using chemiluminescence by a reaction between lucigenin and hydrogen.

The fifth invention is

It is a hydrogen detection reagent consisting of lucigenin. In the third to fifth inventions, the statements made in relation to the first invention hold as long as they do not contradict their properties.

In the present invention configured as described above, the distribution of hydrogen in a material such as a metal can be easily visualized by detecting chemiluminescence caused by a reaction between a chemical reagent and hydrogen using a photodetector. . In addition, the quantitative analysis of hydrogen can be easily performed by measuring the emission intensity. By measuring the position and intensity of this light emission using a CCD camera or the like, it is possible to observe changes in the hydrogen distribution over time in real time, and it is also possible to perform remote measurement by remote control. Brief Description of Drawings

FIG. 1 is a schematic diagram illustrating a hydrogen distribution visualization system according to a first embodiment of the present invention, and FIG. 2 is a luminescence of a lucigenin solution used in the hydrogen distribution visualization system according to the first embodiment of the present invention. The schematic diagram showing the time-dependent change in strength, FIG. 3A, FIG. 3B, FIG. 4, FIG. 5A, FIG. 5B, FIG. 6A and FIG. FIG. 7 is a photograph showing measurement results of chemiluminescence by the hydrogen distribution visualization system according to the first embodiment; FIG. 7 is a schematic diagram showing the hydrogen distribution visualization system according to the second embodiment of the present invention; FIG. FIG. 9 is a schematic diagram illustrating a method for visualizing the distribution of tritium in metal using a camera. FIG. 9 is a photograph showing an example of visualizing the distribution of tritium in metal using a CCD camera. Calculates the distribution of tritium in metals by radioluminography. Is a photograph showing an example in which the deer. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a hydrogen distribution visualization system according to a first embodiment of the present invention.

As shown in FIG. 1, in this hydrogen distribution visualization system, a sample 12 containing hydrogen is placed in a container 11, and the hydrogen is supplied to a depth above the outermost surface of the sample 12. Solution 13 containing a luminescent reagent is contained. A CCD camera 14 is provided above the container 11, and the CCD camera 14 can capture an image of the container 11. As the CCD camera 14, an ultra-high-sensitivity camera capable of detecting each photon is used. The output of the CCD camera 14 is sent to an image intensity controller (not shown) and an image processor, which can display an image on an RGB color monitor and perform predetermined arithmetic processing by a computer. Can be used.

Next, how to use this hydrogen distribution visualization system will be described. First, after a solution 13 containing a luminescent reagent prepared in advance is placed in the container 11, the luminescence intensity of the solution 13 passes through a peak, preferably, for example, 以下 or less of the peak intensity. Leave until the light emission intensity reaches. As a result, background luminescence due to luminescence of the solution 13 itself can be suppressed. Next, the sample 1 containing hydrogen is immersed in the solution 13. Solution 13 should be filled to a depth that completely covers the outermost surface of sample 12. Thus, the solution 13 comes into contact with the surface of the sample 12, and at this time, the luminescent reagent in the solution 13 reacts with hydrogen on the surface of the sample 12 to cause chemiluminescence. This chemiluminescence is imaged by photon count by a CCD camera 14. Here, photon-counting imaging is an imaging method in which an image is created by detecting each photon and accumulating it for a certain period of time. This The image showing the position and intensity of light emission thus captured is displayed on an RGB color monitor.

An example will be described.

Example 1

Lucigenin was used as a luminescent reagent. The lucigenin solution was prepared by dissolving lucigenin in an aqueous NaOH solution. The concentration of NaOH at that time was 10 m 0 1 / m ³ , 20 mo 1 / m ³ , 50 mo 1 / m ³ .100 m 0 / m ^3, and the concentration of lucigenin was 0. It was 1 mo 1 / m ^3.

FIG. 2 shows the time-dependent changes in the luminescence intensity of the lucigenin solution in which the concentration of NaOH was 100 mol / m ³ and the concentration of lucigenin was 0.1 mol / m ³ . Lucigenin emits faint light only when dissolved in an alkaline solution, but as shown in Fig. 2, the luminescence intensity reaches a maximum around 14 hours, and then decays. When measurement is performed using a lucigenin solution in which the luminescence intensity has passed its peak and the luminescence of the solution itself has been suppressed, the distinction between background luminescence and chemiluminescence due to hydrogen becomes clear. For example, when about 30 hours or more have passed since the preparation of the lucigenin solution, the intensity of the background luminescence attenuated to 1/2 or less of the peak intensity.

On the other hand, as the sample 1 2, 5 X 5 X 0. 3 using P d piece cut out in mm ^3, this electrochemical cathodic charging method (electrolyte ^{l kmo 1 / m 3 N a} OH a q., Current Hydrogen was added at a density of 200 A / m ² ) for 2 hours. Then, this hydrogen-added Pd piece was immersed in a lucigenin solution (100 mol / m ³ Na〇H, 0.1 mol / m ³ lucigenin) 36 hours after the preparation, and was placed in a dark place. Then, photon-counting imaging was performed using a CCD camera (C2400-35, manufactured by Hamamatsu Photonics). The results are shown in FIGS. 3A and 3B. Fig. 3A shows an instantaneous still image before photo counting, and Fig. 3B shows the measured photo. It is a ton counting image (photon integrated image). The average intensity (count / pixel) at the positions indicated by 1 to 5 in Fig. 3B is 6 8

3.0, 158.5, 35.9, 42.6, 31.5. In Figs. 3A and 3B, the sample on the right is a Pd piece with hydrogen added, and the sample on the left is a Pd piece without hydrogen. As can be seen from FIG. 3B, the Pd pieces to which hydrogen was added were observed brightly and emitted light, whereas the Pd pieces without hydrogen were hardly observed to emit light. Since only the Pd fragment to which hydrogen was added emits light, it can be seen that this emission is chemiluminescence due to the reaction between the lucigenin solution and hydrogen.

Example 1

Lucigenin was used as a luminescent reagent. The lucigenin solution was prepared by dissolving lucigenin in a Na〇H aqueous solution. At that time, the concentration of NaOH was set to 1 km 01 / m ³ and the concentration of lucigenin was set to 0.1 mo 1 / m ³ .

As Sample 1 2, 5 X 5 X 0 . 3 with P d piece cut out in mm ^3, this electrochemical cathodic charging method (electrolyte ^{1 kmo 1 / m 3 N a} OH a q., The current density 2 At 0 A / m ² ) for 2 hours. Its to the P d pieces with added hydrogen, Rushige Nin solution after three 6 hours after fabrication ^{(1 km 0 1 / m 3} N a 0 H, 0. 1 mo 1 / m 3 Rushige two down) to The sample was immersed, and photon-counting imaging was performed in a dark place using a CCD camera (C2400-35 manufactured by Hamamatsu Photonics). Fig. 4 shows the measured photon counting images. As shown in FIG. 4, it can be seen that light emission occurs so as to border the Pd piece.

Example 3

Lucigenin was used as a luminescent reagent. The lucigenin solution was prepared by dissolving lucigenin in an aqueous NaOH solution. The concentration of NaOH at that time is 1 kmo 1 / m ³ and the concentration of lucigenin was 0.1 mo 1 / m ³ .

As a sample 12, a 5 x 5 x 0.3 mm ³ piece of Fe cut out was used, and this was subjected to an electrochemical cathodic charge method (electrolyte 1 kmo 1 / m ³ NaOH aq., Current density 2 (0 A / m ^z ) for 2 hours. Then, this hydrogen-added Fe piece was placed in a lucigenin solution (1 km 01 / m ³ Na〇H, 0.1 mo 1 / m ³ lucigen) 36 hours after preparation. After immersion, photon counting imaging was performed in a dark place using a CCD camera (C2400-35, manufactured by Hamamatsu Photonics). The measured photon counting images are shown in Figs. 5A and 5B. The sample in Fig. 5A is a piece of Fe without hydrogen, and the sample in Fig. 5B is a piece of Fe with hydrogen added. The average intensity of the photo-counting image in Fig. 5A is 6.145, and the average intensity of the photo-counting image in Fig. 5B is 10.985. As can be seen from FIG. 5B, the F-piece with hydrogen added is brightly observed and emits light, while the F-piece without hydrogen is hardly observed to emit light. From FIG. 5B, it can be seen that the surface of the F e piece emits light almost uniformly. This is considered to be the result of the difference in the way hydrogen invades between the Pd piece and the Pd piece, as shown in Fig. . Since only the Fe fragment to which hydrogen was added emits light, it can be seen that this emission is chemiluminescence due to the reaction between the lucigenin solution and hydrogen.

Example 4

Lucigenin was used as a luminescent reagent. The lucigenin solution was prepared by dissolving lucigenin in an aqueous NaOH solution. The concentration of N a OH at that time is set to 1 kmo 1 / m ^3, the concentration of lucigenin was 0. l mo l / m ^3. As a sample 12, a piece of Ni cut out to 5 × 5 × 0.3 mm ³ was used, and the sample was subjected to an electrochemical cathodic charge method (electrolyte 1 kmo 1 / m ³ NaOH aq., Current density 2 At 0 A / m ² ), hydrogen was added for 24 hours. Then, the hydrogen-added Ni pieces were immersed in a lucigenin solution (1 kmo 1 / m ³ NaOH, 0.1 mol / m ³ lucigenin) 36 hours after the preparation, and were placed in a dark place. Photon-counting imaging was performed using a CCD camera (C2400-35, manufactured by Hamamatsu Photonics). The measured photon counting images are shown in Fig. 6A and Fig. 6B. The sample in Fig. 6A is a piece of Ni without hydrogen, and the sample in Fig. 6B is a piece of Ni with hydrogen added. The average intensity of the photon counting image in Fig. 6A is 14.6.65, and the average intensity of the photon counting image in Fig. 6B is 20.695. As can be seen from FIG. 6B, the Ni-added hydrogen pieces are brightly observed and emit light, whereas the Ni-added pieces without hydrogen hardly emit light. FIG. 6B shows that the surface of the Ni piece emits light almost uniformly. This is thought to be a result of the difference in the way that Pd fragments emit light, as shown in Fig. 4. . Since only the Ni pieces to which hydrogen was added emit light, it can be seen that this emission is chemiluminescence due to the reaction between the lucigenin solution and hydrogen. As described above, according to the first embodiment, the position and intensity of chemiluminescence caused by the reaction between the luminescent reagent and hydrogen can be visualized by photon-counting imaging using the CCD camera 14, The hydrogen distribution in the sample 12 can be easily visualized, and quantitative analysis of hydrogen can be easily performed. In addition, continuous photon-counting imaging by the CCD camera 14 enables real-time observation of changes over time in the hydrogen distribution. The method for visualizing the hydrogen distribution according to the first embodiment greatly contributes to elucidation of the hydrogen release behavior and hydrogen embrittlement mechanism from the sample 12 and improvement of the performance of the hydrogen storage alloy.

Next, a hydrogen distribution visualization system according to a second embodiment of the present invention will be described.

As shown in Fig. 7, in this hydrogen distribution visualization system, a vessel 16 is attached to the outer wall of a high-temperature pipe 15 made of steel material, which is prone to hydrogen embrittlement, so that its open end contacts the outer wall. The solution 13 containing the luminescent reagent is placed in the container 16 and is in contact with the outer wall. The space between the outer wall of the high-temperature pipe 15 and the vessel 16 is sealed with a sealing material (not shown) to prevent the solution 13 from leaking outside. The container 16 is made of a transparent material, or at least the light extraction part is made of a transparent material, and the other part is made of an opaque material. Chemiluminescence resulting from the reaction between the luminescent reagent in 3 and the hydrogen released from the high-temperature tube 15 is emitted to the outside through the wall of the container 16. The container 16 is heated by the heat of the high-temperature pipe 15 to prevent the solution 13 containing the luminescent reagent from evaporating or deactivating the luminescent reagent. As a result, cooling can be performed to a temperature at which no problem occurs. As the cooling device, a device using a refrigerant, an electronic cooling device using the Peltier effect, or the like can be used. A CCD camera 14 is installed outside the container 16, and the CCD camera 14 can take a photon-counting image of the chemiluminescence that comes out through the wall of the container 16. You can do it.

Except for the above, the third embodiment is the same as the first embodiment.

According to the second embodiment, for example, in a nuclear power plant, Early detection of hydrogen embrittlement in the hot piping 15 is extremely important from the viewpoint of safety, but the CCD camera 14 uses a CCD camera 14 to emit chemiluminescence through the wall of the vessel 16. Photon counting can be used to monitor the progress of hydrogen embrittlement in the high-temperature piping 15 at all times, and shut down the nuclear power plant when hydrogen embrittlement reaches a dangerous level And other measures can be taken to improve safety.

Next, a hydrogen distribution visualization system according to a third embodiment of the present invention will be described.

In this hydrogen distribution visualization system, a gel filled with a luminescent reagent is placed in the container 16 of the second embodiment instead of the solution 13 containing the luminescent reagent, and this is used for the high-temperature piping 15. Contacting the outer wall. Except for the above, the third embodiment is the same as the first and second embodiments.

According to the third embodiment, advantages similar to those of the second embodiment can be obtained.

The distribution of tritium in metal can be visualized using a CCD camera. In this method, an ultra-high-sensitivity CCD camera capable of photon-counting imaging is used to detect the scintillation emission due to beta rays emitted from tritium added to the metal sample, and to visualize the distribution of tritium in the metal sample. Specifically, after cutting pure vanadium into a sample of 10 × 10 × 1 mm ³ as a sample, the sample was annealed at 110 ° C. for 24 hours in a vacuum, and then subjected to an electrochemical cathode charging method. To add tritium. In the electrochemical cathodic charging method, 3. 7 PB q / m using H ₂ S 0 ₄ aqueous solution containing ³ tritium a (0. 0 5 kmo l / m 3) as an electrolytic solution, 0 5 at room temperature 0 Electrolysis was performed at A / m ² for 2 hours. As shown in Fig. 8, the tritium-doped surface of sample 21 thus obtained was After the liquid scintillator 22 is dropped on the sample, the plastic scintillator 23 is brought into close contact with the plastic scintillator 23, and the line radiated from the tritium in the sample 21 changes to the liquid scintillator 1 and the plastic scintillator 1 The scintillation luminescence generated when the light enters 23 is detected by an ultra-sensitive CCD camera 24. By measuring the two-dimensional distribution of scintillation light emission for 14 hours using this CCD camera 24 and obtaining a photon counting image, the position and intensity of light emission can be measured. Fig. 9 shows the obtained photon counting image. The average intensities (counts / pixel) at the positions indicated by 1 to 4 in Fig. 9 are 33.8, 35.4, 9.7, and 10.7, respectively, and the total is 12.7. is there. As can be seen from FIG. 9, the emission intensity varied depending on the position on Sample 21, and the distribution of tritium on Sample 21 was observed. For comparison, Fig. 10 shows the results of measuring the distribution of tritium by radioluminography using the same sample 21. Comparing FIG. 10 with FIG. 9, it can be seen that almost the same results were obtained.

In a device that measures the risk of hydrogen embrittlement by scintillation light emitted from a tritium line added to a metal sample and emitted by a scintillation line, it is used in a liquid scintillation counter instead of the CCD camera described above. It is also possible to attach a gel-like scintillator plastic scintillator to a reactor pipe or the like using a photomultiplier tube to detect.

Although the embodiments and examples of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments and examples, and various modifications based on the technical idea of the present invention are possible. It is.

For example, the numerical values, configurations, materials, raw materials, processes, and the like described in the above-described embodiments and examples are merely examples, and may be used as needed. Different values, configurations, materials, raw materials, processes, etc. may be used. As described above, according to the present invention, the distribution of hydrogen in various materials including metals can be easily visualized, and quantitative analysis of hydrogen and real-time observation of hydrogen distribution can be performed with high resolution. It is possible. This invention can be used to analyze the behavior of hydrogen in areas where hydrogen embrittlement is a problem, such as high-temperature piping in nuclear power plants and various products using high-strength steel, and to monitor the performance of hydrogen storage alloys and fuel cell materials. Various applications such as observation of hydrogen behavior are possible.

Claims

The scope of the claims

1. A method for visualizing hydrogen distribution, characterized by visualizing hydrogen distribution in materials using chemiluminescence.

2. The method for visualizing a hydrogen distribution according to claim 1, wherein the hydrogen distribution is visualized as a position and intensity distribution of the luminescence by detecting the chemiluminescence using a photodetector.

3. The light detection device is a CCD camera, and the hydrogen distribution is visualized as a distribution of the position and intensity of light emission by imaging the chemiluminescence using the CCD camera. The method for visualizing the hydrogen distribution described in item 1.

4. The method for visualizing hydrogen distribution according to claim 1, wherein a luminescent reagent is brought into contact with the material.

5. The method for visualizing hydrogen distribution according to claim 1, wherein the material is brought into contact with a solution containing a luminescent reagent or a gel impregnated with the solution.

6. The visualization of hydrogen distribution according to claim 1, wherein after the solution containing the luminescent reagent is prepared, the solution is brought into contact with the material after the luminescence intensity from the solution has passed its peak. Method.

7. The method for visualizing hydrogen distribution according to claim 1, wherein lucigenin is used as a luminescent reagent.

8. A hydrogen distribution visualization system characterized by visualizing the hydrogen distribution in materials using chemiluminescence.

9. Having a contact body containing a luminescent reagent and a photodetector, detecting the chemiluminescence caused when the luminescent reagent of the contact body is brought into contact with the material using the photodetector. Claim 8 featuring the feature The hydrogen distribution visualization system described in the paragraph.

10. The hydrogen distribution according to claim 9, characterized in that the hydrogen distribution is visualized as a distribution of the position and intensity of light emission by detecting the chemiluminescence using the photodetector. Visualization system.

11. The photodetector is a CCD camera, and the chemiluminescence is imaged by using the CCD camera to visualize the hydrogen distribution as a position and intensity distribution of light emission. Item 10. A hydrogen distribution visualization system according to Item 10.

12. The hydrogen distribution visualization system according to claim 8, wherein the contact body has a solution containing the luminescent reagent.

13. The hydrogen distribution visualization system according to claim 8, wherein the contact body has a gel impregnated with a solution containing the luminescent reagent.

14. The hydrogen distribution according to claim 8, wherein after preparing the solution containing the luminescent reagent, the solution is brought into contact with the material after the luminescence intensity from the solution has passed its peak. Visualization system.

15. The hydrogen distribution visualization system according to claim 8, wherein lucigenin is used as a luminescent reagent.

16. Luminescent reagent for visualizing hydrogen distribution consisting of lucigenin.

17. A method for detecting hydrogen, characterized by using chemiluminescence due to the reaction between lucigenin and hydrogen.

1 8. Hydrogen detection reagent consisting of lucigenin.