JP2006000820A - Catalytic body, its manufacturing method and hydrogen generating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalytic body which is used for generating hydrogen by bringing, for example, a hydrogen generating agent into contact with the catalytic body, the surface area of which to be in contact with the hydrogen generating agent is enlarged so that the catalysis can be advanced in high efficiency and the catalysis of which with the hydrogen generating agent is stabilized. <P>SOLUTION: This catalytic body is manufactured by integrally covering the surface of a metallic base material with a molten nickel-based alloy being a catalytic metal. As a result, many fine cracks are produced on the surface of the catalytic metal and the surface is roughened so that the surface area of the catalytic metal to be in contact with the hydrogen generating agent is enlarged. Therefore, this catalytic body can be reacted with the hydrogen generating agent in high efficiency. Since the catalytic metal is not exfoliated from the metallic base material, the catalysis with the hydrogen generating agent is stabilized for a long time. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a catalyst body used, for example, for hydrogen generation, a method for producing the same, and a method for generating hydrogen using the catalyst body.

  A method for generating hydrogen from an alkaline aqueous solution in which a metal hydrogen complex compound such as tetrahydroborate is dissolved using a catalytic metal is generally known. For example, in Patent Document 1, a metal such as nickel (Ni) or cobalt (Co) or a hydrogen storage alloy such as magnesium-nickel (Mg—Ni) alloy or a fluorinated product thereof is used as a catalyst metal. There has been proposed a method of generating hydrogen by dipping a catalyst metal mechanically pulverized into powder into an alkaline aqueous solution in which a metal-hydrogen complex compound is dissolved.

  Further, in an apparatus for continuously generating hydrogen industrially, a method in which an alkaline aqueous solution of a metal hydrogen complex compound is generally passed through a catalyst body in which a catalyst metal is supported on a metal substrate is useful. Thus, the catalyst body in which the catalyst metal is supported on the metal substrate is a support body having a predetermined shape such as a rod shape, a plate shape, a columnar shape, a porous shape, a porous block shape, a net shape or a foam shape. A surface of a metal substrate such as nickel is coated with a catalyst metal such as platinum by coating, coating, baking, spraying, plating or thermal spraying (for example, see Patent Document 2).

  Further, for example, Patent Document 3 describes that a powder of a hydrogen storage alloy is sintered and formed into a plate shape, and this is used as a catalyst body for hydrogen generation.

  Under such a background, the present inventor has paid attention to Mg2Ni as a hydrogen storage alloy suitable for generating hydrogen by contacting an alkali aqueous solution of a metal hydrogen complex compound, and has conducted research. This Mg2Ni is used as a powder in Patent Document 1. For example, a commercially available Mg2Ni powder is put in a net-like bag and placed in a reaction vessel containing an alkali aqueous solution of a metal hydride complex compound. When immersed, the particle size of the powder is as small as 25 to 45 μm, so that there is a problem that the powder flows out from the mesh bag.

  Patent Document 2 describes or suggests a catalyst body in which the surface of a nickel foam as a metal substrate is coated with Mg2Ni as a catalyst metal by a method of filling, adhesion, plating, and CVD. Since the generation of hydrogen gas is extremely intense on the surface, the method of filling, adhering and plating has a problem that the catalyst metal is easily peeled off or dropped off from the metal substrate as the support. In particular, in the adhesion and plating methods, hydrogen generation occurs violently from the coating surface at the boundary between the metal coating on the edge of the metal substrate and the metal substrate, which turns the metal coating on the edge of the metal substrate. It has been confirmed that once turning occurs, hydrogen is generated on the back side of the turning surface, and peeling progresses. Further, although a CVD method has been suggested, it is questionable whether an apparatus for producing the catalyst body is large, and in addition to that, it is possible to deposit a catalyst metal to the inside of the porous portion of the nickel foam.

  In addition, when the surface of the nickel foam is coated with the catalyst metal Mg2Ni by a thermal spraying method, the Mg2Ni must be heated to a melting point of 600 ° C. or higher. There is a problem that the catalytic surface area of the catalytic metal to be contacted is reduced, and the catalytic activity is impaired.

  Further, in Patent Document 3, Mg2Ni powder, which is a catalyst metal, is formed into a plate shape by sintering, and when this plate-like Mg2Ni is used as a metal substrate, the Mg2Ni powder is also made to have a melting point of 600 ° C. or higher. A similar problem arises because the surface must be heated and smoothed.

  In addition, the activity of the catalyst body is also determined by the reaction surface area of the catalyst metal in contact with the metal hydride complex compound, but the nickel foam itself does not have a very large surface area, so that a large hydrogen generation rate cannot be obtained. There are also challenges.

JP 2001-19401 (Claims 2, 4, 5, paragraphs 009, 0010, 0012, 0013) JP 2002-29702 (Claim 1, paragraphs 0009, 0013, 0017, 0018, 0024) JP-A-2002-68701 (Claim 1, paragraph 0014)

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a catalyst body suitable for a hydrogen generation catalyst, for example, having a large surface area and being physically stable. . Another object is to provide a suitable method for producing such a catalyst body. Furthermore, another object is to provide a hydrogen generation method in which the catalyst body is suitably used.

  The catalyst body of the present invention is characterized in that a nickel base alloy is melt-integrated and coated on the surface of a metal substrate. The nickel-based alloy is preferably a nickel-based hydrogen storage alloy. Examples of the nickel hydrogen storage alloy include Mg2Ni alloys, Mg2Ni alloys such as eutectic alloys of Mg2Ni and Mg, ZrNi2 alloys, ZrNi2 alloys, and LaNi5 alloys. Among these, magnesium-nickel hydrogen storage alloys are used. An alloy such as Mg2Ni is preferred. Here, as the shape of the metal substrate, for example, a plate shape, a rod shape, a block shape, a cylindrical shape, a columnar shape, a conical shape, a prismatic shape, and a rod shape are used, or a porous body (foamed body) is formed into these shapes. You may use what you did. This metal base material does not contain powder as described in the prior art, and cannot pass in any direction when trying to pass the metal base material through a round hole having a diameter of 10 mm, for example. , Or something that may not pass when it is pointed in a certain direction. For example, when the metal substrate is turned sideways, it can pass through the round hole, but when it is turned vertically, it means that it may not pass. Furthermore, the weight of one metal substrate is preferably 0.6 g or more because of ease of handling. Moreover, a nickel base material may be used as the metal base material, and other metals may be used.

  The method for producing a catalyst body of the present invention comprises a step of coating magnesium on the surface of a nickel base, and then a step of heating the nickel base to a eutectic temperature of Mg2Ni or higher. . As another method of manufacturing this Mg2Ni, there are a step of coating the surface of the metal base material by melting and integrating nickel, and then a step of coating the surface of the nickel coating the metal base material with magnesium. And then heating to a temperature equal to or higher than the eutectic temperature of Mg2Ni, or a step of coating the surface of the metal substrate with magnesium and nickel, and then the eutectic of Mg2Ni And a method of heating to a temperature or higher. As a preferred method of using the catalyst body of the present invention, for example, a method of generating hydrogen gas by applying to a hydrogen generator and contacting with an alkali aqueous solution of a metal hydrogen complex compound can be mentioned. In this case, the metal hydrogen complex compound is preferably tetrahydroborate.

  According to the catalyst body of the present invention, a nickel-based alloy, which is a catalyst metal, is fused and integrated on the surface of a metal substrate, so that many fine cracks are generated on the surface of the catalyst metal and the surface becomes rough. Since the surface area of the catalyst is increased, the catalytic reaction can proceed with high efficiency. Further, since the catalyst metal does not peel off or hardly occurs from a metal substrate such as a nickel substrate, for example, the catalytic reaction with a metal hydride complex compound is stabilized for a long time.

  If, for example, Mg2Ni is used as the nickel-based alloy, the catalyst body can be obtained by heating nickel and magnesium to a temperature equal to or higher than the eutectic temperature of Mg2Ni. That is, according to this method, a catalyst can be obtained without heating to the melting point of Mg2Ni, so that a larger surface area can be obtained than when a sintered body is obtained by heating the Mg2Ni powder to the melting point or higher. Therefore, when this catalyst body is applied to a hydrogen generator, a large hydrogen generation rate can be obtained, it is easy to control, and continuous hydrogen generation can be performed stably.

(First embodiment)
1st Embodiment of the manufacturing method of the catalyst body which concerns on this invention is described. For example, magnesium powder with an average particle size of 25 μm or less is coated on the surface of a nickel base material, which is a plate-like metal base material, and coated with the adhesive, for example, methylcellulose, on the surface of the nickel base material. By heating to a temperature of 506 ° C. or higher, the nickel base material and the magnesium powder are fused and alloyed (melted and integrated) to obtain Mg 2 Ni. In this case, it is only necessary to heat the eutectic temperature or higher, so there is no point in heating more than necessary. Therefore, this heating temperature is naturally lower than the melting point of Mg2Ni. If a large amount of unreacted magnesium powder remains on the surface of the nickel base after producing Mg2Ni, it may be removed by, for example, sandpaper. As a method of coating and coating magnesium on the surface of the nickel metal, a method of spraying magnesium on the surface of the nickel base material may be adopted, or magnesium may be sputtered and particles thereof may be applied to the surface of the nickel base material. A deposition method may be employed.

  The shape of the metal substrate is not limited to a plate shape, and a rod-like, block-like, cylindrical, columnar, conical, prismatic or rod-like metal substrate may be used, or a porous body ( A foam formed into these shapes may be used, but in order to prevent the catalyst from flowing out, the weight is preferably 0.6 g or more.

  According to such a manufacturing method, Mg2Ni which is a catalyst metal is generated on the surface of a nickel substrate which is a metal substrate.

  According to the catalyst body manufactured according to such an embodiment, Mg2Ni as the catalyst metal is fused and integrated on the surface of the nickel base that is the metal base, so there is a possibility that Mg2Ni may be peeled off from the nickel base. Therefore, for example, when applied to a hydrogen generator as described later, the catalytic reaction with the hydrogen complex compound is stabilized for a long time. Further, by heating the nickel base material to a Mg2Ni eutectic temperature of 506 ° C. or more, many fine cracks are generated on the surface of Mg2Ni and the surface becomes rough, and the Mg2Ni powder is not heated to the melting point or higher. As a result, smoothening of the rough surface is avoided, and as a result, a catalyst body having a large surface area can be obtained.

  Further, when this catalyst body is applied to, for example, a hydrogen generator described later, the catalyst body is formed by melting and integrating the catalyst metal Mg2Ni on the surface of nickel itself as the metal base material. As supported by the examples, the catalyst metal can hardly be peeled off or dropped off, so that a decrease in the catalyst activity can be suppressed, and continuous hydrogen generation can be performed stably. Furthermore, since the degree of freedom of the form of the catalyst body is large, it is possible to appropriately create a form (for example, shape and size) according to the application location, so that the degree of freedom in designing the reactor is increased and the handling is convenient. It also has the effect of becoming.

(Second Embodiment)
A second embodiment of the method for producing a catalyst body according to the present invention will be described. First, for example, nickel (Ni) powder is coated and coated on the surface of a metal base material together with an adhesive such as methyl cellulose on the surface of a metal base material made of, for example, plate-like iron, and heated to the temperature of the melting point of nickel in a heating furnace. Then, nickel is melted and integrated with the metal substrate to obtain a metal substrate coated with nickel. Subsequently, for example, magnesium (Mg) powder having an average particle size of 25 μm or less is coated on the surface of the metal substrate and coated on the surface of nickel together with an adhesive such as methylcellulose, and the eutectic temperature of Mg 2 Ni is 506 ° C. in a heating furnace. Heat to the above to obtain an Mg2Ni alloy. If a large amount of unreacted magnesium powder remains on the surface of the nickel base after producing Mg2Ni, it may be removed by, for example, sandpaper. Further, as described above, a thermal spraying method or a sputtering method may be adopted as a method of coating the surface of the metal substrate with nickel powder or a method of coating the nickel surface with magnesium powder.

  As the metal substrate, in addition to iron (Fe), cobalt (Co), copper (Cu), chromium (Cr), manganese (Mn), aluminum (Al), titanium (Ti) and zirconium (Zr), or , Selected from these alloys and the like. Further, nickel-based alloys such as nickel-iron and nickel-cobalt may be used. As the shape of the metal substrate, the shape of the metal substrate described in the first embodiment can be used.

  Also by such a manufacturing method, a catalyst body can be obtained in which the surface of the metal substrate is coated by melting and integrating the catalyst metal Mg2Ni.

  According to the catalyst body manufactured by such an embodiment, for example, nickel is melted and integrated on the surface of a metal substrate made of plate-like iron, and the nickel and magnesium are alloyed. There is no possibility that Mg2Ni peels from the substrate, and the catalytic reaction with the hydrogen complex compound is stable for a long time. Further, since the catalyst body made of Mg2Ni can be obtained by heating at a Mg2Ni eutectic temperature of 506 ° C. or higher, the same effects as those of the first embodiment can be obtained.

  As another example of the manufacturing method of this embodiment, first, magnesium (Mg) powder is applied to the surface of a metal substrate together with, for example, methylcellulose as an adhesive, on the surface of a metal substrate made of, for example, plate-like iron. Then, it is heated to the temperature of the melting point of magnesium in a heating furnace, and the magnesium is melted and integrated with the metal substrate to obtain a metal substrate coated with magnesium. Subsequently, for example, nickel (Ni) powder having an average particle size of 25 μm or less is coated on the surface of the metal substrate and coated on the surface of magnesium together with, for example, methylcellulose as an adhesive, and the eutectic temperature of Mg 2 Ni is 506 ° C. in a heating furnace. Heat to the above to obtain an Mg2Ni alloy. Even in this case, Mg2Ni similar to the above can be formed on the surface of the metal substrate.

(Third embodiment)
A third embodiment of the method for producing a catalyst body according to the present invention will be described. For example, a mixed powder in which nickel powder having an average particle diameter of 25 μm or less and magnesium powder having an average particle diameter of 25 μm or less are mixed at a molar ratio of 1: 2 on the surface of a metal substrate made of plate-like iron is an adhesive. For example, it is coated and coated on the surface of a metal substrate together with methylcellulose, and heated to a Mg2Ni eutectic temperature of 506 ° C. or higher in a heating furnace to fuse the metal substrate and the mixed powder to form an alloy (melt integration). . When the mixing ratio of nickel powder and magnesium powder deviates from the molar ratio of 1: 2 and either nickel or magnesium is in an excess state, a large number of nickel or magnesium single metal is mixed in the produced Mg2Ni. As a result, there is a concern that the catalytic activity of the Mg2Ni catalyst is inferior, so that the mixing ratio is preferably as close to 1: 2 as possible. The metal substrate described in the second embodiment can be used as the metal substrate, and the shape of the metal substrate described in the first embodiment is used as the shape of the metal substrate. be able to.

  Also by such a manufacturing method, the catalyst body formed by melting and coating the catalyst metal Mg2Ni on the surface of the metal base material can be obtained, and the same effect as the previous embodiment can be obtained.

(Application example of catalyst body)
Next, an example of a hydrogen generator using the catalyst body manufactured as described above will be briefly described with reference to FIG. FIG. 1 is a plan view showing an example of a hydrogen generator. In this figure, the hydrogen generating agent is disposed in the hydrogen generating section 4 from the raw material storage section 1 through the regulating valve 2 and the raw material supply pipe 3. For example, it is supplied to the upper end portion 51 of the plate-like catalyst body 5 of the present invention. As the hydrogen generator supplied here, an alkaline aqueous solution in which a metal hydrogen complex compound such as tetrahydroborate is dissolved is used. For example, a solution obtained by dissolving sodium borohydride (NaBH4), which is a metal hydride complex compound, in an aqueous solution of sodium hydroxide (NaOH), which is an alkaline aqueous solution, is used. This hydrogen generating agent normally does not generate hydrogen gas because the properties of sodium borohydride are stable in an alkali. When this hydrogen generating agent comes into contact with the catalyst body 5, it causes a chemical reaction as shown in the following formula (1). Hydrogen gas is generated.

NaBH4 + 2H2O → NaBO2 + 4H2 (1)
The supplied hydrogen generating agent flows along both surfaces of the catalyst body 5 and flows down while forming a thin film, and reaches the lower end portion 52 of the catalyst body 5, during which the metal hydrogen complex compound (1) The hydrolysis reaction shown in the equation is performed to generate hydrogen gas, and this hydrogen gas is taken out from the hydrogen gas outlet 6. In addition, the metal hydride complex is oxidized during this period to be converted into an oxide, and the alkaline aqueous solution containing the oxide is collected in the recovery unit 7. In the figure, 8 is a flange for connecting the raw material storage unit 1 and the hydrogen generation unit 4, 9 is a support rod for the raw material supply pipe 3, and 91 is a hanger.

  FIG. 2 is a partial side view showing a contact portion between the raw material supply pipe 3 and the plate-like catalyst body 5, and both sides of the front end portion of the raw material supply pipe 3 supported by the support rod 9 via the hanger 91. The upper part of the catalyst body 5 is inserted between the walls with a slight gap, and the hydrogen generating agent flows down to both surfaces of the catalyst body 5 through the gap.

  Since the catalyst body 5 can secure a large surface area as described above, the hydrogen generation rate is increased and the catalytic metal cannot be peeled off or dropped off, so that the catalytic activity does not decrease. Continuous hydrogen generation can be performed stably.

  Further, as another embodiment using the catalyst body of the present invention, for example, a plurality of plate-like catalyst bodies are arranged in a reaction container containing a predetermined amount of an alkali aqueous solution of a metal hydride complex and arranged at predetermined intervals. In this reaction vessel, hydrogen gas may be generated by a hydrolysis reaction by contacting the metal hydride complex compound with the catalyst body. By providing the catalyst bodies with a predetermined interval in this way, hydrogen gas generated between the catalyst bodies can be easily released.

  Next, an experiment conducted for confirming the effect of the present invention will be described.

A. Experimental example [Manufacture of catalyst body]
Example 1
On a surface of 0.24 g of a sponge-like nickel foam (20 mm × 30 mm) as a metal substrate, 0.19 g of magnesium powder having a particle size of 25 μm or less was mixed with methylcellulose as an adhesive, and then coated. The nickel foam was heated to 660 ° C. at a temperature rising rate of 5 ° C./min in a heating furnace under an argon atmosphere, and the surface Ni and the coated Mg were alloyed by heating for 30 minutes. Thereafter, it was naturally cooled, and the surface of a nickel foam as a metal substrate was fused and coated with magnesium to obtain a catalyst body made of Mg2Ni. This catalyst body is referred to as Example 1.

(Example 2)
The surface of the catalyst body was fluorinated by immersing the catalyst body obtained in Example 1 in a mixed solution of 0.6 wt% HF liquid and 0.06 wt% KF liquid. This catalyst body is referred to as Example 2.

(Comparative Example 1)
A commercially available Mg2Ni powder having a particle size of 25 to 45 μm (2.0 g) was placed in a mesh bag to form a catalyst body. This catalyst body is referred to as Comparative Example 1.

(Comparative Example 2)
Thermal spray substrate: Sprayed on a surface of SUS304 (45 mm × 75 mm × 2 mm) with a spray metal of Mg 2 Ni having an average particle size of 75 μm or less, which is a catalyst metal, at a thermal spray temperature of 600 ° C. toward the thermal spray substrate by an atmospheric plasma method. A catalyst body with Mg2Ni coated on the surface was obtained. This catalyst body is referred to as Comparative Example 2.

[Crystal structure analysis by X-ray diffraction method]
(A) of FIG. 3 is an analysis of the crystal structure of Mg2Ni powder (Comparative Example 1) marketed by X-ray diffraction method. The X-ray count value (cps) is taken on the vertical axis, and the horizontal axis is taken. FIG. 5 is a characteristic diagram that takes a wave number (cm ⁻¹ ) and represents the characteristics of this crystal structure as a spectrum. FIG. 3 (b) is an analysis of the crystal structure of the catalyst body 1 by the X-ray diffraction method. The vertical axis represents the X-ray count value (cps), and the horizontal axis represents the wave number (cm ⁻¹ ). FIG. 5 is a characteristic diagram showing the characteristics of this crystal structure as a spectrum. In (b) of FIG. ^3, 2000 cm -1, it is possible to confirm the same peaks as shown in FIG. 3 (a) to 4000 cm ^-1 and 7200cm ^-1. Therefore, in Example 1, it can be understood that Mg2Ni is generated on the surface of the Ni foam.

[Hydrogen generation and specific surface area]
In three reaction vessels containing 50 ml of an aqueous solution prepared by dissolving 10 g of sodium borohydride (NaBH4) in 90 ml of a 10% by weight aqueous sodium hydroxide solution, the catalyst bodies of Example 1, Example 2 and Comparative Example 1 Were immersed in each reaction vessel, and the hydrogen generation rate generated at a reaction temperature of 80 ° C. was measured. In addition, the specific surface area, which is the sum of the surface areas of the substances per gram of the catalyst bodies of Example 1, Example 2 and Comparative Example 1, was determined for each particle using the Scherrer equation from the half-value width of the diffraction peak obtained from the X-ray diffraction method. Obtained by calculating the diameter. FIG. 4 shows the result. As can be seen from FIG. 4, it can be understood that Example 1 has a larger hydrogen generation capability than Comparative Example 1. Presuming this from the results of the specific surface area, the catalyst body of Example 1 has Mg2Ni formed by alloying Mg on the surface of the nickel foam, and therefore the surface of the Mg2Ni surface has many fine cracks. As a result of roughening, a larger surface area can be secured than in the case of using Mg2Ni powder, and as a result, it is assumed that the reaction area in contact with the aqueous solution is increased and the capability of hydrogen generation is increased.

  Moreover, from the result of the hydrogen generation rate of Example 2, the ability to generate hydrogen can be further improved by fluorinating the catalyst body of Example 1. Since the specific surface area of Example 2 is also increased, it is surmised that the surface of Mg2Ni was further roughened by fluorination treatment, the reaction area in contact with the aqueous solution was increased, and the hydrogen generation capability was further increased. . Further, the catalyst body of Comparative Example 2 was immersed in a reaction vessel containing 50 ml of an aqueous solution prepared by dissolving 10 g of sodium borohydride (NaBH4) in 90 ml of a 10% by weight sodium hydroxide aqueous solution, and Mg2Ni produced by hydrogen generation. The exfoliation and drop-off were observed visually. As a result, a hydrogen generation reaction was shown immediately after the catalyst body was added. After several tens of minutes, peeling started so that the edge portion of the sprayed substrate turned up, and the reaction vessel was left to stand overnight and then observed again, and it was confirmed that the edge portion of the sprayed substrate was peeled off. However, the central part did not appear to peel off at all. From this, it is presumed that the adhesion of the thermal spray coating is reduced at the edge portion of the thermal spray substrate.

It is a top view which shows an example of the apparatus used in order to implement the catalyst body which concerns on this invention. It is a partial side view which shows the contact part of the raw material supply pipe | tube of FIG. 1, and a plate-shaped catalyst body. It is the characteristic view which analyzed the crystal structure of each catalyst body by the X ray diffraction method. It is a figure showing the results of hydrogen generation rate and specific surface area of each catalyst body,

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Raw material storage part 2 Control valve 3 Raw material supply pipe 4 Hydrogen generating part 5 Catalytic body 51 Upper end part 52 of catalytic body 5 Lower end part 6 of catalytic body 5 Hydrogen gas outlet 7 Recovery part 8 Flange 9 Supporting rod 91 Hanging tool

Claims (10)

  A catalyst body, wherein a nickel base alloy is melt-integrated and coated on the surface of a metal substrate.   The catalyst body according to claim 1, wherein the nickel-based alloy is a nickel-based hydrogen storage alloy.   The catalyst body according to claim 2, wherein the nickel-based hydrogen storage alloy is a magnesium-nickel-based hydrogen storage alloy.   The catalyst body according to claim 3, wherein the magnesium-nickel-based hydrogen storage alloy is Mg2Ni.   The catalyst body according to any one of claims 1 to 4, wherein the metal substrate is a nickel substrate. Coating the surface of the nickel base with magnesium;
And a step of heating the nickel substrate to a temperature equal to or higher than the eutectic temperature of Mg2Ni. A step of melting and integrating nickel on the surface of the metal substrate; and
Next, a step of coating magnesium on the surface of nickel coating the metal substrate,
And a step of heating to a temperature equal to or higher than the eutectic temperature of Mg2Ni. Coating the surface of the metal substrate with magnesium and nickel;
And a step of heating to a temperature equal to or higher than the eutectic temperature of Mg2Ni.   A hydrogen generating method, wherein the catalyst body according to any one of claims 1 to 5 is brought into contact with an alkali aqueous solution of a metal hydrogen complex compound to generate hydrogen gas. The method for generating hydrogen according to claim 9, wherein the metal hydride complex compound is tetrahydroborate.

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