JP4665656B2 - Hydrogen permeable membrane and method for producing hydrogen permeable membrane - Google Patents

Description

  The present invention relates to a hydrogen permeable membrane that selectively permeates hydrogen and a method for manufacturing the hydrogen permeable membrane.

  In order to extract hydrogen from a hydrogen-containing gas, a hydrogen permeable membrane containing a hydrogen permeable metal made of palladium (Pd) has been conventionally used. As such a hydrogen permeable membrane, a metal layer containing Pd is provided on the surface of a metal layer made of a metal having high hydrogen permeable performance (for example, niobium (Nb), tantalum (Ta), vanadium (V)). A hydrogen permeable membrane whose performance is improved by adopting a structure is known (for example, see Patent Document 1).

JP-A-11-276866 JP-A-7-185277

  However, the hydrogen permeable membrane having the multilayer structure has a problem that the hydrogen permeation performance is gradually lowered when used under a predetermined high temperature condition. Such a problem is caused by, for example, oxygen entering the hydrogen permeable membrane through the Pd layer provided on the surface of the hydrogen permeable membrane, and the metal constituting the metal layer having the high hydrogen permeable performance inside the hydrogen permeable membrane. It is thought to occur by being oxidized. Alternatively, such a problem is that the metal constituting the layer made of the metal having high hydrogen permeation performance or the metal oxide diffuses in the metal layer containing Pd, and the metal layer containing Pd. It is thought to occur by reaching the surface of

  The present invention has been made in order to solve the above-described conventional problems, and an object of the present invention is to suppress performance deterioration in the hydrogen permeable membrane.

In order to achieve the above object, a method for producing a first hydrogen permeable membrane of the present invention comprises:
(A) a first step of preparing a metal base layer containing a Group 5 metal and a second component that can be oxidized, nitrided or carbonized;
(B) forming a multilayer structure by forming a predetermined metal layer on the surface of the metal base layer, and forming a metal coating layer containing palladium (Pd) on the surface of the multilayer structure. A second step;
And (c) a third step which is a densification step of oxidizing, nitriding or carbonizing the second component.

  According to the first method for producing a hydrogen permeable membrane of the present invention configured as described above, the second component contained in the metal base layer is oxidized, nitrided, or carbonized, so that the metal base layer has a dense structure. Oxides, nitrides or carbides can be formed. Therefore, by suppressing entry of oxygen into the metal base layer with such a dense oxide, nitride, or carbide, oxidation of the Group 5 metal constituting the metal base layer can be suppressed. Thereby, the performance fall of the hydrogen permeable film resulting from oxidation of a group 5 metal can be suppressed. Further, by forming a dense oxide, nitride or carbide, it is possible to suppress the movement of the Group 5 metal constituting the metal base layer and the oxide of this Group 5 metal to the metal coating layer side. . Therefore, it is possible to suppress the degradation of the performance of the hydrogen permeable membrane caused by the Group 5 metal or Group 5 metal oxide reaching the surface of the hydrogen permeable membrane.

In the first method for producing a hydrogen permeable membrane of the present invention,
The metal base layer prepared in the first step may include the second component only in a limited region including the surface of the metal base layer.

  With such a configuration, it is possible to suppress a decrease in hydrogen permeation performance in the metal base layer resulting from the provision of the second component.

In the first method for producing a hydrogen permeable membrane of the present invention,
In the second step, when forming the predetermined metal layer on the metal base layer in the second step, the second component is formed after forming at least a part of the predetermined metal layer. It is good also as a process of oxidizing, nitriding or carbonizing.

  With such a configuration, oxide, nitride, or carbide is formed on the surface of the metal base layer at a position corresponding to the gap on the crystal structure of at least a part of the predetermined metal layer. Therefore, it is possible to suppress a decrease in the performance of the hydrogen permeable membrane due to the formation of oxides, nitrides or carbides.

The second method for producing a hydrogen permeable membrane of the present invention is as follows.
(A) a first step of preparing a metal base layer containing a Group 5 metal;
(B) a second step of forming an intermediate layer containing a second component that can be oxidized, nitrided or carbonized on the metal base layer;
(C) a third step of forming a metal coating layer containing palladium (Pd) on the intermediate layer;
(D) A fourth step is a densification step of oxidizing, nitriding or carbonizing the second component.

  According to the second method for producing a hydrogen permeable membrane of the present invention configured as described above, the second component contained in the intermediate layer is oxidized, nitrided, or carbonized, so that the intermediate layer is densely oxidized. , Nitrides or carbides can be formed. Therefore, such dense oxides, nitrides or carbides can suppress the intrusion of oxygen into the metal base layer and suppress the oxidation of the group 5 metal constituting the metal base layer. Thereby, the performance fall of the hydrogen permeable film resulting from oxidation of a group 5 metal can be suppressed. Moreover, the movement of the Group 5 metal constituting the metal base layer and the oxide of this Group 5 metal to the metal coating layer side can be suppressed by a dense oxide, nitride, or carbide. Therefore, it is possible to suppress the degradation of the performance of the hydrogen permeable membrane caused by the Group 5 metal or Group 5 metal oxide reaching the surface of the hydrogen permeable membrane.

In the second method for producing a hydrogen permeable membrane of the present invention,
In addition to the second component, the intermediate layer formed in the second step may further include a refractory metal having a melting point higher than that of the metal base layer and the metal coating layer.

  With such a configuration, the effect of suppressing metal diffusion in the hydrogen permeable membrane can be enhanced by providing the intermediate layer.

In the second method for producing a hydrogen permeable membrane of the present invention,
The second step is a step of forming the intermediate layer composed of a first layer disposed on the metal base layer side and a second layer disposed on the metal coating layer side,
The first layer may have a higher content of the refractory metal and a lower content of the second component than the second layer.

  In the hydrogen permeable membrane thus manufactured, metal diffusion can be suppressed by the first layer. The second layer suppresses oxygen from entering the intermediate layer and suppresses movement of the Group 5 metal constituting the metal base layer and the oxide of the Group 5 metal toward the metal coating layer. can do.

In the above-described second method for producing a hydrogen permeable membrane of the present invention,
The fourth step may be a step of oxidizing, nitriding or carbonizing the second component after the third step.

  With such a configuration, oxide, nitride, or carbide is formed in the intermediate layer at a position corresponding to the gap on the crystal structure of the metal coating layer. Therefore, it is possible to suppress a decrease in the performance of the hydrogen permeable membrane due to the formation of oxides, nitrides or carbides.

In the method for producing the first or second hydrogen permeable membrane of the present invention,
The second component is selected from chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe), copper (Cu), molybdenum (Mo), and zirconium (Zr). Element,
The densification step may be a step of oxidizing the second component.

  With such a configuration, a denser oxide can be formed by using the second component described above, and the effect of suppressing the intrusion of oxygen and the movement of the Group 5 metal and its oxide can be achieved. Can be increased.

In the method for producing the first or second hydrogen permeable membrane of the present invention,
The second component is an element that forms, together with the Group 5 metal, a composite oxide having a melting point higher than the melting point of the Group 5 metal oxide,
The densification step may be a step of oxidizing the second component.

  With such a configuration, the oxide obtained by oxidizing the second component is a complex oxide having a melting point higher than that of the Group 5 metal. The effect of suppressing the movement of the oxide can be enhanced. As the second component forming such a complex oxide having a high melting point, for example, an element selected from chromium (Cr), magnesium (Mg), and calcium (Ca) can be used.

In the first method for producing a hydrogen permeable membrane of the present invention,
The second component may be an element that is more easily oxidized than the Group 5 metal.

  With such a configuration, in the metal base layer, the second component is oxidized in preference to the Group 5 metal, so that the performance degradation of the hydrogen permeable membrane due to the oxidation of the Group 5 metal can be suppressed. . Examples of metals that can be oxidized more easily than Group 5 metals that can be used as the second component include aluminum (Al), silicon (Si), titanium (Ti), zirconium (Zr), tantalum (Ta), and gadolinium ( Examples include elements selected from Gd), niobium (Nb), tungsten (W), cerium (Ce), yttrium (Y), ytterbium (Yb), neodymium (Nd), and praseodymium (Pr).

In the method for producing the first or second hydrogen permeable membrane of the present invention,
The second component is an element selected from chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe),
The densification step may be a step of nitriding the second component.

  With such a configuration, a denser nitride can be formed by using the above-described second component, and the effect of suppressing the intrusion of oxygen and the movement of the Group 5 metal and its oxide can be achieved. Can be increased.

In the first method for producing a hydrogen permeable membrane of the present invention,
The second component may be an element that is more easily nitrided than the Group 5 metal.

  With such a configuration, in the metal base layer, the second component is nitrided in preference to the Group 5 metal, so that it is possible to suppress the deterioration of the performance of the hydrogen permeable film due to the nitridation of the Group 5 metal. . Examples of metals that can be more easily nitrided than Group 5 metals that can be used as the second component include aluminum (Al), silicon (Si), titanium (Ti), zirconium (Zr), magnesium (Mg), and calcium ( An element selected from Ca) and boron (B) can be mentioned.

In the method for producing the first or second hydrogen permeable membrane of the present invention,
The second component is an element selected from silicon (Si) and titanium (Ti),
The densification step may be a step of carbonizing the second component.

  With such a configuration, a denser carbide can be formed by using the second component described above, and the effect of suppressing the intrusion of oxygen and the movement of the Group 5 metal and its oxide is enhanced. be able to.

In the first method for producing a hydrogen permeable membrane of the present invention,
The second component may be an element that is more easily carbonized than the Group 5 metal.

  With such a configuration, since the second component is carbonized in preference to the Group 5 metal in the metal base layer, it is possible to suppress the performance degradation of the hydrogen permeable membrane due to the carbonization of the Group 5 metal. . The metal that is more easily carbonized than the Group 5 metal that can be used as the second component is selected from, for example, chromium (Cr), titanium (Ti), zirconium (Zr), tantalum (Ta), and molybdenum (Mo). Can be mentioned.

The third method for producing a hydrogen permeable membrane of the present invention is as follows.
(A) a first step of preparing a metal base layer containing a Group 5 metal, the metal base layer containing a second component which can be oxidized, nitrided or carbonized at least in a region including the surface of the metal base layer When,
(B) When forming a multilayer structure by sequentially forming a predetermined metal layer on the surface of the metal base layer containing the second element, the metal coating layer containing palladium (Pd) And a second step of forming on the surface of the multilayer structure.

  According to the third method for producing a hydrogen permeable membrane of the present invention configured as described above, by performing further oxidation, nitridation, or carbonization treatment, at least the surface of the metal base layer has a dense oxide, nitridation. Or carbides can be formed. In addition, if the environment in which the hydrogen permeable membrane is used is an environment in which an oxidation reaction, nitridation reaction or carbonization reaction can proceed with respect to the second component, the oxide, nitride or carbide is formed during the use of the hydrogen permeable membrane. Can be made. Therefore, such dense oxides, nitrides or carbides can suppress the intrusion of oxygen into the metal base layer and suppress the oxidation of the group 5 metal constituting the metal base layer.

The fourth method for producing a hydrogen permeable membrane of the present invention is as follows.
(A) a first step of preparing a metal base layer containing a Group 5 metal;
(B) a second step of forming an intermediate layer containing a second component that can be oxidized, nitrided or carbonized on the metal base layer;
And (c) a third step of forming a metal coating layer containing palladium (Pd) on the intermediate layer.

  According to the fourth method for producing a hydrogen permeable membrane of the present invention configured as described above, a dense oxide, nitride, or carbide is formed in the intermediate layer by performing further oxidation, nitridation, or carbonization treatment. Can be formed. In addition, if the environment in which the hydrogen permeable membrane is used is an environment in which an oxidation reaction, nitridation reaction or carbonization reaction can proceed with respect to the second component, the oxide, nitride or carbide is formed during the use of the hydrogen permeable membrane. Can be made. Therefore, such dense oxides, nitrides or carbides can suppress the intrusion of oxygen into the metal base layer and suppress the oxidation of the group 5 metal constituting the metal base layer.

  The present invention can be realized in various forms other than the above, for example, a form of a hydrogen permeable film manufactured by the method for manufacturing a hydrogen permeable film of the present invention, a hydrogen extraction apparatus using the hydrogen permeable film, a fuel cell, or the like. This can be realized.

Next, embodiments of the present invention will be described in the following order based on examples.
A. Configuration of hydrogen permeable membrane:
B. Production method of the hydrogen permeable membrane of the first embodiment:
C. Modification of the first embodiment:
D. Second embodiment:
E. Modification of the second embodiment:
F. Equipment using hydrogen permeable membrane:
G. Variations:

A. Configuration of hydrogen permeable membrane:
FIG. 1 is a schematic cross-sectional view showing an outline of the configuration of a hydrogen permeable membrane 10 according to the first embodiment. The hydrogen permeable membrane 10 has a five-layer structure including a metal base layer 12, an intermediate layer 14 formed on both surfaces of the metal base layer, and a metal coating layer 16 formed on each intermediate layer 14. is doing.

  The metal base layer 12 is formed of a metal containing V, such as vanadium (V) or a vanadium alloy containing V as a main component in a proportion exceeding 50%, and is a metal layer exhibiting excellent hydrogen permeability. is there. More specifically, the metal base layer 12 of the present embodiment is formed of an alloy of V and chromium (Cr). The metal base layer 12 of this embodiment is characterized by including a predetermined oxide at a crystal grain boundary included in the metal base layer 12, and the detailed configuration of the metal base layer 12 will be described later.

  The metal coating layer 16 is made of a metal containing Pd, such as a palladium (Pd) alloy containing Pd as a main component in a proportion exceeding 50%. The metal coating layer 16 is a layer that functions as a catalyst layer having an activity of promoting the dissociation reaction of hydrogen molecules on the surface of the hydrogen permeable membrane or the binding reaction to hydrogen molecules.

  The intermediate layer 14 is a layer made of a hydrogen permeable metal having a composition different from that of the metal base layer 12 and the metal cover layer 16, and prevents metal diffusion between the metal base layer 12 and the metal cover layer 16. It is a layer to be provided. In this embodiment, the intermediate layer 14 is formed of tantalum (Ta).

B. Production method of the hydrogen permeable membrane of the first embodiment:
FIG. 2 is a process diagram showing a method for manufacturing the hydrogen permeable membrane 10. When manufacturing the hydrogen permeable membrane 10, first, a metal layer containing V to be the metal base layer 12 is prepared (step S100). The metal layer prepared in step S100 can be produced, for example, by repeating the rolling and annealing steps on an alloy ingot containing Cr as a main component and further containing Cr. Thereby, the metal base layer 12 having a crystal structure as a whole is obtained. In step S100, the surface of the prepared metal layer is etched with an alkaline solution to remove impurities such as an oxide film formed on the surface.

  After step S100, an intermediate layer 14 made of Ta is formed on each of both surfaces of the prepared metal base layer 12 (step S110). The intermediate layer 14 can be formed by, for example, a PVD method, a CVD method, or a plating process such as electroless plating or electrolytic plating.

  Once the intermediate layer 14 is formed, next, the metal coating layer 16 containing Pd is formed on each intermediate layer 14 (step S120), and a laminate having a five-layer structure is formed. The metal coating layer 16 can be formed by, for example, a PVD method, a CVD method, or a plating process such as electroless plating or electrolytic plating.

After the metal coating layer 16 is formed, if the laminated body provided with the metal coating layer 16 is oxidized (step S130), Cr is oxidized on the surface of the metal base layer 12 and chromium oxide (Cr ₂ O ₃ ) is produced. Further, it further reacts with V constituting the metal base layer 12 to form a composite oxide of chromium oxide and vanadium oxide ( V ₂ O ₅ · Cr ₂ O ₃ ). Thereby, the hydrogen permeable membrane 10 is completed. Here, the oxidation treatment can be, for example, a heat treatment in an oxidizing atmosphere. That is, the laminated body may be exposed to a high-temperature oxidizing atmosphere, whereby Cr contained in the metal base layer 12 is oxidized. The temperature at which the oxidation treatment is performed may be a temperature lower than the melting point of the metal constituting the laminate, and the oxidation reaction can be activated by increasing the temperature, but the metal that proceeds in the laminate during the oxidation treatment It is desirable to set the temperature so that diffusion is suppressed to an acceptable level. Therefore, the conditions for the oxidation treatment can be, for example, about 2 to 10 hours at 400 to 500 ° C. in the air. Note that the oxidation treatment in step S130 may be anodic oxidation, ozone heat treatment, or oxygen plasma treatment in addition to the heat treatment in the oxidizing atmosphere.

  Since the metal base layer 12, the intermediate layer 14, and the metal coating layer 16 all have a crystal structure, a crystal grain boundary is formed between the crystal grains constituting these layers. This crystal grain boundary is a portion where the crystal lattice constituting the crystal structure is discontinuous, and can be said to be a fine gap existing in the crystal structure. When the oxidation treatment is performed in step S130, oxygen enters from the outside of the laminated body into the laminated body. At this time, oxygen enters mainly through gaps on the crystal structure including the crystal grain boundaries in each layer. When oxygen that has entered through the gaps in the crystal structure of the metal coating layer 16 and the intermediate layer 14 reaches the surface of the metal base layer 12, it reacts with Cr in the metal base layer 12 to produce chromium oxide, Furthermore, it reacts with V to produce the composite oxide described above. FIG. 3 is a cross-sectional view schematically showing how oxides and composite oxides are formed on the surface of the metal base layer 12 in contact with the intermediate layer 14. As shown in FIG. 3, in the metal base layer 12, the oxide and the composite oxide are formed at positions corresponding to the crystal grain boundaries of the intermediate layer 14. By sufficiently performing the oxidation treatment step in step S130, most of the generated oxide can be made into a composite oxide. At this time, in the region where chromium oxide and composite oxide are formed in the metal base layer 12, the crystal structure constituting the metal base layer 12 expands with oxidation. Therefore, at the contact surface between the metal base layer 12 and the intermediate layer 14, the crystal grain boundary of the intermediate layer 14 is blocked by a dense oxide (chromium oxide and composite oxide) formed on the surface of the metal base layer 12. It will be in the state.

  When the hydrogen permeable membrane 10 is manufactured, the thickness of each layer may be set according to the hydrogen permeation performance and strength required based on the application. For example, the metal base layer can be 10 to 100 μm. The metal coating layer 16 can be 0.1 to 1.0 μm. Since the metal coating layer 16 is a layer that functions as a catalyst layer as described above, it can be made thinner than the metal base layer 12. In addition, the intermediate layer 14 is desirably formed thicker in order to prevent metal diffusion between the metal base layer 12 and the metal coating layer 16, but prevents metal diffusion if interposed between the both. Therefore, it may be formed thinner than the metal coating layer 16. Therefore, for example, the thickness can be about 0.01 to 10 μm.

According to the hydrogen permeable membrane 10 of the present example configured as described above, a dense oxidation is performed on the surface of the metal base layer 12 in contact with the intermediate layer 14 and at a position corresponding to the crystal grain boundary of the intermediate layer 14. In other words, since an oxide of Cr including a complex oxide is formed, oxygen can be effectively prevented from entering the metal base layer 12. By suppressing the intrusion of oxygen into the metal base layer 12, it is possible to suppress a decrease in hydrogen permeation performance in the metal base layer 12 due to oxidation of V constituting the metal base layer 12. Further, according to the present embodiment, since the Cr oxide containing the composite oxide is formed at a position corresponding to the crystal grain boundary of the intermediate layer 14, the metal base layer is interposed via the crystal grain boundary of the intermediate layer 14. The movement of V from 12 to the upper layer including the intermediate layer 14 can be effectively suppressed. In particular, when V is oxidized, vanadium oxide (V ₂ O ₅ ) having a lower melting point is formed. However, since such a low melting point compound moves more easily in the hydrogen permeable membrane than V, the hydrogen permeable membrane. The hydrogen permeation performance is easily lowered by reaching the surface and hindering the catalytic activity of the metal coating layer. As in this example, the oxidation of V constituting the metal base layer 12 is prevented, and the movement of the generated vanadium oxide is suppressed, so that the performance deterioration in the hydrogen permeable membrane can be suppressed. The composite oxide produced by the oxidation treatment is a high melting point composite oxide having a higher melting point than vanadium oxide, and therefore has a property that it is difficult to move in the hydrogen permeable membrane. Oxygen penetration and movement of V or vanadium oxide can be effectively prevented.

  Further, in the hydrogen permeable membrane 10 of the present example, since the intermediate layer 14 and the metal coating layer 16 are formed on the metal base layer 12 and then the oxidation treatment in step S130 is performed, the crystal structure in the intermediate layer 14 is obtained. The high melting point composite oxide is formed only in the upper gap, that is, the position corresponding to the route of oxygen intrusion and movement of V and vanadium oxide. Therefore, it is possible to suppress the decrease in hydrogen permeation performance in the metal base layer 12 due to the formation of the composite oxide while obtaining the effect of suppressing the entry of oxygen and the movement of V and vanadium oxide.

  In addition, you may perform the oxidation process in step S130 after step S110 which forms the intermediate | middle layer 14 instead of step S120 which forms the metal coating layer 16. FIG. Also in this case, a similar effect can be obtained by forming an oxide or a high melting point composite oxide at a position corresponding to the gap on the crystal structure in the intermediate layer 14 on the surface of the metal base layer 12.

  In addition, the Cr content in the metal base layer 12 is determined by the degree of the effect described above obtained by forming a dense oxide (composite oxide) or the hydrogen in the metal base layer 12 resulting from the addition of Cr. What is necessary is just to set suitably in consideration of the grade of the permeation | transmission performance fall.

C. Modification of the first embodiment:
(C-1) First modification:
In the first embodiment, the oxidation process is performed after the upper layers such as the intermediate layer 14 and the metal coating layer 16 are formed on the metal base layer 12, but the oxidation process of step S130 is performed prior to the formation of the upper layer. May be. That is, prior to step S110, for example, heat treatment in an oxidizing atmosphere, ozone heat treatment, or oxygen plasma treatment may be performed. In this case, an oxide of Cr is formed on the entire surface of the metal base layer 12.

(C-2) Second modification:
In the first embodiment, the entire metal base layer 12 contains Cr, but may have a different configuration. For example, only the vicinity of the contact surface with the intermediate layer 14 where the oxide is to be formed may contain Cr. FIG. 4 shows a configuration in which only the vicinity of the surface of the metal base layer 12 contains Cr. With such a configuration, the content of V in other regions not containing Cr increases, so that the hydrogen permeation performance in the metal base layer 12 can be improved.

  In order to contain Cr only in the vicinity of the surface of the metal base layer 12, for example, an alloy of V and Cr is formed on a vanadium layer made of V or a V alloy not containing Cr produced in the same manner as in step S100. The film may be formed by PVD or CVD. Alternatively, Cr may be diffused in the vanadium layer by forming a Cr layer on the vanadium layer and then performing a heat treatment.

(C-3) Third modification:
The oxidation process in step S130 in the first embodiment may be omitted, and the laminate having the five-layer structure may be used as a hydrogen permeable film without performing the oxidation process. In this case, while the laminate is used as a hydrogen permeable membrane, oxidation gradually proceeds at a position corresponding to the gap on the crystal structure of the intermediate layer 14 on the surface of the metal base layer 12. The same effects as in the embodiment are obtained.

(C-4) Fourth modification:
In the first embodiment, Cr is used as the second component added to the metal base layer 12 in order to form a dense oxide that prevents oxygen intrusion and movement of V and vanadium oxide. It may be used as the second element. As the second component added to the metal base layer 12 to form an oxide, for example, in addition to chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe) , Copper (Cu), molybdenum (Mo), zirconium (Zr), magnesium (Mg), calcium (Ca), tantalum (Ta), gadolinium (Gd), niobium (Nb), tungsten (W), cerium (Ce) , Yttrium (Y), ytterbium (Yb), neodymium (Nd), and praseodymium (Pr).

  Here, the second component is selected from chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe), copper (Cu), molybdenum (Mo), and zirconium (Zr). In particular, an oxide having particularly high density can be formed. Therefore, by oxidizing the second component, it is possible to obtain a more sufficient effect of preventing the invasion of oxygen and the movement of V and vanadium oxide.

If the second component is an element selected from chromium (Cr), magnesium (Mg), and calcium (Ca), a high melting point composite oxide can be formed together with V by oxidation treatment. That is, V ₂ O ₅ · Cr ₂ O ₃ , 3MgO · V ₂ O ₅ or 3CaO · V ₂ O ₅ is formed as the high melting point composite oxide. By forming such a high-melting-point composite oxide that does not easily move in the metal film, it is possible to enhance the effect of preventing the entry of oxygen and the movement of V and vanadium oxide.

  Alternatively, the second component may be chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), zirconium (Zr), tantalum (Ta), gadolinium (Gd), niobium (Nb), tungsten (W ), Cerium (Ce), yttrium (Y), ytterbium (Yb), neodymium (Nd), and praseodymium (Pr), the effect of suppressing oxidation of V constituting the metal base layer 12 is achieved. Can be further enhanced. That is, the above-described elements have a property that they are more easily oxidized than V. Therefore, if these elements are included in the metal base layer 12, the second component is oxidized prior to V. The progress of oxidation of V during use of the hydrogen permeable membrane can be suppressed.

(C-5) Fifth modification:
In the first embodiment, the second component added to the metal base layer 12 is oxidized to form a dense oxide, thereby suppressing oxygen intrusion and movement of V and vanadium oxide. The components may be nitrided or carbonized to form dense nitrides or carbides.

  For example, chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), the second component contained in the metal base layer 12 in order to form a nitride in the vicinity of the contact surface with the intermediate layer 14. If an element selected from iron (Fe) is used, the effect of forming a dense nitride can be enhanced. If an element selected from aluminum (Al), silicon (Si), titanium (Ti), zirconium (Zr), magnesium (Mg), calcium (Ca), and boron (B) is used as the second component. For example, these elements have a property that they are more easily nitrided than V. Therefore, the progress of nitriding of V during the use of the hydrogen permeable membrane is suppressed, and the deterioration of the hydrogen permeation performance due to the nitriding of V is suppressed. be able to.

  When the second component is nitrided as described above, a nitridation process may be performed instead of the oxidation process in step S130. As the nitriding treatment, for example, a heat treatment in a nitrogen atmosphere or a nitrogen plasma treatment may be performed.

  Alternatively, for example, if an element selected from silicon (Si) and titanium (Ti) is used as the second component to be contained in the metal base layer 12 in order to form carbide in the vicinity of the contact surface with the intermediate layer 14 The effect by forming a dense carbide can be enhanced. If an element selected from chromium (Cr), titanium (Ti), zirconium (Zr), tantalum (Ta), and molybdenum (Mo) is used as the second component, these elements are carbonized rather than V. Since it has the property of being easily treated, the progress of carbonization of V during the use of the hydrogen permeable membrane can be suppressed, and the decrease in hydrogen permeation performance due to the carbonization of V can be suppressed.

  When the second component is carbonized as described above, a carbonization process may be performed instead of the oxidation process in step S130. As the carbonization treatment, for example, a heat treatment in a carbon-containing gas (for example, hydrocarbon gas) atmosphere or a carbon plasma treatment may be performed.

  As described above, when the second component is nitrided or carbonized instead of being oxidized, the same modification as in the first embodiment is possible. For example, only the surface of the metal base layer 12 includes the second component for forming the nitride or carbide, or in the process of use as a hydrogen permeable film without special nitriding or carbonizing treatment. Similar modifications can be made, such as nitridation or oxidation.

(C-6) Sixth modification:
In the first embodiment, the intermediate layer 14 is provided between the metal base layer 12 and the metal coating layer, but the intermediate layer 14 may not be provided. That is, a metal coating layer containing Pd may be directly formed on the metal base layer 12 made of a V alloy containing Cr. Such a configuration is shown in FIG. Even when the metal coating layer 16 is directly formed on the metal base layer 12, an oxide is formed in the vicinity of the surface of the metal base layer 12 at a position corresponding to the crystal structure gap in the metal coating layer 16. The same effect as the embodiment can be obtained.

D. Second embodiment:
Similar to the hydrogen permeable membrane 10 of the first embodiment shown in FIG. 1, the hydrogen permeable membrane of the second embodiment has a five-layer structure including a metal base layer 12, an intermediate layer 14, and a metal coating layer 16. Have. In the hydrogen permeable membrane of the second embodiment, unlike the hydrogen permeable membrane 10 of the first embodiment, not the metal base layer 12 but the intermediate layer 14 contains Cr.

  When manufacturing the hydrogen permeable membrane of the second embodiment, first, the metal base layer 12 is prepared in the same manner as in the first embodiment shown in FIG. 1 (step S100). The metal base layer 12 prepared in the second embodiment may be produced in the same manner as the metal base layer 12 in the first embodiment, but does not contain Cr as described above and is formed of V or a V alloy. Is done. Thereafter, an intermediate layer is formed on the metal base layer 12 (step S110). In the second embodiment, an intermediate layer made of an alloy of Ta and Cr is formed. The intermediate layer 14 may be formed by, for example, PVD or CVD as in the first embodiment. Next, a metal coating layer 16 similar to that of the first embodiment is formed on the intermediate layer 14 (step S120), and an oxidation treatment is further performed (step S130), thereby completing a hydrogen permeable membrane.

  FIG. 6 is a cross-sectional view schematically showing how an oxide is formed on the surface of the intermediate layer 14 in contact with the metal coating layer 16. The metal coating layer 16 has a crystal structure, and oxygen penetrates into the hydrogen permeable film through a gap on the crystal structure such as a crystal grain boundary in the metal coating layer 16. Chromium oxide is formed at a position corresponding to the gap on the crystal structure in the metal coating layer 16. Here, since the intermediate layer 14 also has a crystal structure, the oxidation of Cr proceeds mainly on the surface of the crystal grains on the surface of the intermediate layer 14. In this way, the crystal grains expand at the portion where the oxidation of Cr proceeds on the surface of the intermediate layer 14, and the gaps on the crystal structure are narrowed / closed. Therefore, by oxidizing the Cr by performing the oxidation treatment, the position corresponding to the gap on the crystal structure of the metal coating layer 16 on the surface of the intermediate layer 14 can be densified.

  According to the hydrogen permeable membrane of the second embodiment configured as described above, the position corresponding to the gap on the crystal structure of the metal coating layer 16 on the surface of the intermediate layer 14 is densified. Oxygen can be prevented from entering the water. Accordingly, it is possible to suppress a decrease in hydrogen permeation performance due to oxidation of the hydrogen permeable metal, and formation of low melting point vanadium oxide due to oxidation of V constituting the metal base layer 12. Furthermore, even when V or vanadium oxide has moved from the metal base layer 12, V or vanadium oxide is transferred to the surface of the hydrogen permeable membrane through the crystal grain boundary of the metal coating layer 16 due to the dense oxide. It can suppress moving.

Further, in the hydrogen permeable membrane of this example, even when V and vanadium oxide migrate from the metal base layer 12 during use of the hydrogen permeable membrane, chromium oxide reacts with V and vanadium oxide, A high-melting-point composite oxide ( V ₂ O ₅ · Cr ₂ O ₃ ) is formed. As described above, when the dense oxide becomes a high melting point composite oxide, the effect of suppressing the movement of V or vanadium oxide toward the metal coating layer 16 can be further enhanced.

  Further, in the hydrogen permeable membrane of the second example, since the oxidation treatment of step S130 is performed after the metal coating layer 16 is formed on the intermediate layer 14, the gap on the crystal structure in the metal coating layer 16, that is, Oxides are formed only at positions corresponding to the routes of oxygen penetration and movement of V and vanadium oxide. Therefore, it is possible to suppress the deterioration of the hydrogen permeation performance in the intermediate layer 14 due to the formation of the oxide while obtaining the effect of suppressing the entry of oxygen and the movement of V and vanadium oxide.

  Note that the Cr content ratio in the intermediate layer 14 is the degree of the above-described effect obtained by forming a dense oxide (composite oxide) or the hydrogen permeation performance in the intermediate layer 14 resulting from the addition of Cr. It may be set as appropriate in consideration of the degree of the decrease.

E. Modification of the second embodiment:
(E-1) First modification:
In the second embodiment, the oxidation treatment is performed after the metal coating layer 16 as the upper layer is formed on the intermediate layer 14, but prior to the formation of the upper layer, that is, prior to step S120, the oxidation treatment of step S130. May be performed. In this case, an oxide of Cr is formed on the entire surface of the intermediate layer 14.

(E-2) Second modification:
In the second embodiment, the intermediate layer 14 is formed of an alloy containing Ta and Cr, but may have a different configuration. For example, the entire intermediate layer 14 may be formed of Cr. Even in such a configuration, Cr oxide is formed on the surface of the intermediate layer 14 made of Cr at a position corresponding to the gap on the crystal structure in the metal coating layer 16, so that the same effect as in the second embodiment is achieved. Can be obtained.

  Alternatively, Cr may be contained only in the vicinity of the contact surface with the metal coating layer 16 in the intermediate layer 14. FIG. 7 shows a configuration in which only the vicinity of the contact surface with the metal coating layer 16 in the intermediate layer 14 contains Cr. With such a configuration, the content of Ta in other regions not containing Cr increases, so that the hydrogen permeation performance in the intermediate layer 14 can be improved.

  In order to contain Cr only in the vicinity of the surface of the intermediate layer 14, for example, a tantalum layer is first formed using Ta as a film forming material on the metal base layer 12 prepared in step S100, and then Ta and Cr An alloy layer of Ta and Cr may be formed using as a film forming material. The film formation can be performed by, for example, PVD or CVD. Alternatively, Cr may be diffused in the tantalum layer by forming a Cr layer on the tantalum layer and then performing a heat treatment.

  Further, the intermediate layer 14 may have a two-layer structure including a tantalum layer and a chromium layer. In this case, it is particularly desirable to form a tantalum layer on the metal base layer 12 side and a chromium layer on the metal coating layer 16 side. That is, in the intermediate layer 14, it is desirable to relatively increase the Ta content ratio on the metal base layer 12 side and increase the Cr content ratio on the metal coating layer 16 side. By providing a chromium layer on the metal coating layer 16 side that is further away from the metal base layer 12 and forming chromium oxide, the effect of suppressing the arrival of oxygen to the metal base layer 12 can be enhanced.

(E-3) Third modification:
The oxidation process of step S130 in the second embodiment may be omitted, and the laminate having a five-layer structure may be used as a hydrogen permeable film without performing the oxidation process. In this case, while the laminate is used as a hydrogen permeable membrane, oxidation gradually proceeds at the position corresponding to the gap on the crystal structure of the metal coating layer 16 on the surface of the intermediate layer 14. The same effects as in the embodiment are obtained.

(E-4) Fourth modification:
As the second component to be contained in the intermediate layer 14 in order to form an oxide, various elements similar to the fourth modification of the first embodiment can be selected in addition to Cr. Also in this case, by oxidizing the second component to form a dense oxide, it is possible to obtain the same effect that hinders the intrusion of oxygen and the movement of V and vanadium oxide.

  Here, the second component is selected from chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe), copper (Cu), molybdenum (Mo), and zirconium (Zr). In particular, an oxide having particularly high density can be formed. Therefore, by oxidizing the second component, it is possible to obtain more sufficiently the effect of preventing the invasion of oxygen and the movement of V and vanadium oxide.

  If the second component is an element selected from chromium (Cr), magnesium (Mg), and calcium (Ca), V and vanadium oxide move to the intermediate layer 14 during use of the hydrogen permeable membrane. Accordingly, a composite oxide with vanadium oxide is further formed from the oxide of the second component. By forming such a high-melting-point composite oxide that does not easily move in the metal film, it is possible to enhance the effect of preventing the entry of oxygen and the movement of V and vanadium oxide.

(E-5) Fifth modification:
Alternatively, as the second component to be included in the intermediate layer 14 in order to densify the intermediate layer 14, an element similar to that of the fifth modification example of the first embodiment is selected and replaced with the oxidation treatment in step S130. Nitriding treatment or carbonizing treatment may be performed. Even in such a configuration, as in the case of performing the oxidation treatment, it is possible to obtain the same effect that prevents oxygen intrusion and movement of V and vanadium oxide by densifying at least a part of the intermediate layer 14. .

  The second component to be included in the intermediate layer 14 for forming the nitride is selected from, for example, chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), and iron (Fe). It is desirable to use elements. In this case, the effect of forming dense nitride can be enhanced. Moreover, it is desirable to use, for example, an element selected from silicon (Si) and titanium (Ti) as the second component contained in the intermediate layer 14 in order to form carbide. Thereby, the effect by forming a dense carbide can be enhanced.

  As described above, when the second component is nitrided or carbonized instead of being oxidized, the same modification as in the second embodiment is possible. For example, only the surface of the intermediate layer 14 may include the second component for forming the nitride or carbide, or the entire intermediate layer 14 may be configured by the second component. Alternatively, nitridation or oxidation may be advanced in the course of use as a hydrogen permeable film without special nitridation or carbonization treatment.

F. Equipment using hydrogen permeable membrane:
(F-1). Hydrogen extraction equipment:
FIG. 8 is a schematic cross-sectional view showing the configuration of the hydrogen extraction device 20 using the hydrogen permeable membrane (hereinafter referred to as the hydrogen permeable membrane 10) of the first embodiment or the second embodiment. The hydrogen extraction device 20 has a structure in which a plurality of hydrogen permeable membranes 10 are stacked. FIG. 8 shows only the configuration related to the stacking of the hydrogen permeable membranes 10. In the hydrogen extraction device 20, a support portion 22 that is joined to the outer peripheral portion of the hydrogen permeable membrane 10 is disposed between the stacked hydrogen permeable membranes 10, and a predetermined portion is provided between the hydrogen permeable membranes 10 by the support portion 22. A space is formed. The support portion 22 may be bonded to the hydrogen permeable membrane 10 and has sufficient rigidity. For example, by forming with a metal material such as stainless steel (SUS), it is possible to easily join the hydrogen permeable membrane 10 which is a metal layer.

  The predetermined spaces formed between the hydrogen permeable membranes 10 alternately form hydrogen-containing gas paths 24 and purge gas paths 26. A hydrogen-containing gas to be subjected to hydrogen extraction is supplied to each hydrogen-containing gas passage 24 from a hydrogen-containing gas supply unit (not shown). A purge gas having a sufficiently low hydrogen concentration is supplied to each purge gas passage 26 from a purge gas supply unit (not shown). Hydrogen in the gas supplied to the hydrogen-containing gas passage 24 is extracted from the hydrogen-containing gas by permeating the hydrogen permeable membrane 10 toward the purge gas passage 26 according to the hydrogen concentration difference.

  According to such a hydrogen extraction apparatus 20, since the lowering of the performance due to the oxidation of the lower layer metal of the hydrogen permeable membrane or the movement of the lower layer metal to the surface is suppressed, the hydrogen extraction performance of the entire hydrogen extraction apparatus 20 is suppressed. Can be prevented.

(F-2). Fuel cell:
FIG. 9 is a schematic cross-sectional view showing an example of the configuration of a fuel cell using the hydrogen permeable membrane 10. Although FIG. 9 shows a single cell 30, the fuel cell is formed by stacking a plurality of the single cells 30.

  The single cell 30 includes a hydrogen permeable membrane 10, an electrolyte layer 32 formed on one surface of the hydrogen permeable membrane 10, and a cathode electrode 34 formed on the electrolyte layer 32. 31 is provided. The single cell 30 further includes two gas separators 36 and 37 that sandwich the MEA 31 from both sides. Between the hydrogen permeable membrane 10 and the gas separator 36 adjacent thereto, a single-cell fuel gas flow path 38 through which a hydrogen-containing fuel gas passes is formed. In addition, between the cathode electrode 34 and the gas separator 37 adjacent thereto, an in-single cell oxidizing gas passage 39 through which an oxidizing gas containing oxygen passes is formed.

The electrolyte layer 32 is a layer made of a solid electrolyte having proton conductivity, for example, a BaCeO ₃ or SrCeO ₃ ceramic proton conductor. The electrolyte layer 32 can be formed by generating the solid oxide on the hydrogen permeable membrane 10 by a method such as PVD or CVD. Thus, by forming the electrolyte layer 32 on the hydrogen permeable membrane 10 which is a dense metal film, the electrolyte layer 32 can be made thinner, and the membrane resistance of the electrolyte layer 32 can be further reduced. Thereby, it becomes possible to generate electric power at about 200 to 600 ° C., which is lower than the operating temperature of the conventional solid oxide fuel cell.

  The cathode electrode 34 is a layer having catalytic activity that promotes an electrochemical reaction, and may be formed of, for example, a porous Pt layer made of noble metal Pt. In the single cell 30, a current collector having electrical conductivity and gas permeability may be further provided between the cathode electrode 34 and the gas separator 37 or between the hydrogen permeable membrane 10 and the gas separator 36.

  The gas separators 36 and 37 are gas-impermeable members formed of a conductive material such as carbon or metal. On the surfaces of the gas separators 36 and 37, a predetermined uneven shape for forming the single-cell fuel gas flow path 38 or the single-cell oxidizing gas flow path 39 is formed.

  According to such a fuel cell, since the lowering of the performance due to the oxidation of the lower layer metal of the hydrogen permeable membrane or the movement of the lower layer metal to the surface is suppressed, the lowering of the performance of the entire fuel cell can be prevented. .

  In the hydrogen permeable membrane provided in the fuel cell shown in FIG. 9, unlike the hydrogen permeable membrane 10 shown in FIG. 1, the metal coating layer and the intermediate layer are not provided on the surface in contact with the electrolyte layer 32. Is also possible. Further, when manufacturing a fuel cell including the hydrogen permeable membrane 10, the oxidation treatment in step S130 may be performed after the electrolyte layer 32 is formed on the hydrogen permeable membrane 10.

G. Variations:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

G1. Modification 1:
You may form each layer which comprises a hydrogen permeable film with the metal different from 1st Example or 2nd Example. For example, in the embodiment, the metal base layer 12 is formed of a metal having V or V as a main component, but may be formed of a metal (including a simple substance) containing another group 5 metal.

  Further, in the intermediate layer 14 of the example, Ta is included as a metal constituting the intermediate layer 14 together with Cr, but if metal diffusion between the metal base layer 12 and the metal coating layer 16 can be suppressed, Different hydrogen permeable metals may be used. In particular, the metal constituting the intermediate layer 14 is preferably formed of a metal having a higher melting point than the metal base layer 12 and the metal coating layer 16 (hereinafter referred to as a refractory metal). Since a metal having a high melting point generally has a property that it is difficult to diffuse the metal, the effect of preventing metal diffusion can be enhanced by forming the intermediate layer 14 with a high melting point metal. For example, in addition to Ta, niobium (Nb), which is the same Group 5 metal, is preferable because it has sufficient hydrogen permeation performance and is a high melting point metal.

G2. Modification 2:
In the hydrogen permeable membrane of the first embodiment or the second embodiment, the hydrogen permeable membrane is a self-supporting membrane of a metal thin film having hydrogen permeability. However, the hydrogen permeable metal is formed on a porous substrate having gas permeability. A hydrogen permeable membrane may be formed by supporting it. That is, a metal layer laminated in the order of a metal coating layer, an intermediate layer, a metal base layer, an intermediate layer, and a metal coating layer may be sequentially formed on a thin plate-like porous body to form a hydrogen permeable membrane. Thus, the hydrogen permeable membrane carry | supported on the porous base material can be used instead of the hydrogen permeable membrane 10 of an Example in the hydrogen extraction apparatus shown in FIG. 8, for example. For example, in the case where the hydrogen permeable membrane of the first embodiment is applied to the above-described configuration, after the hydrogen permeable membrane is formed on the porous body, the whole is oxidized to form the intermediate layer 14 in the metal base layer 12. Chromium oxide may be formed at a position corresponding to the gap on the crystal structure.

It is a cross-sectional schematic diagram showing the outline of a structure of the hydrogen permeable film of 1st Example. It is process drawing showing the manufacturing method of the hydrogen permeable film of 1st Example. It is sectional drawing which shows typically a mode that complex oxide is formed in the metal base layer surface. It is sectional drawing which shows typically the structure of the 2nd modification of 1st Example. It is sectional drawing which shows typically the structure of the 6th modification of 1st Example. It is sectional drawing which shows typically a mode that an oxide is formed in the intermediate | middle layer 14 surface. It is sectional drawing which shows typically the structure of the 1st modification of 2nd Example. It is a cross-sectional schematic diagram showing the structure of a hydrogen extraction apparatus. It is a cross-sectional schematic diagram showing an example of a structure of a fuel cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Hydrogen permeable membrane 12 ... Metal base layer 14 ... Intermediate | middle layer 16 ... Metal coating layer 20 ... Hydrogen extraction apparatus 22 ... Supporting part 24 ... Hydrogen-containing gas path 26 ... Purge gas path 30 ... Single cell 31 ... MEA
32 ... Electrolyte layer 34 ... Cathode electrode 36, 37 ... Gas separator 38 ... Fuel gas flow path in single cell 39 ... Oxidizing gas flow path in single cell

Claims (28)

A method for producing a hydrogen permeable membrane that selectively permeates hydrogen,
(A) a first step of preparing a metal base layer containing a Group 5 metal and a second component that can be oxidized, nitrided or carbonized;
(B) forming a multilayer structure by forming a predetermined metal layer on the surface of the metal base layer, and forming a metal coating layer containing palladium (Pd) on the surface of the multilayer structure. A second step;
(C) A hydrogen permeable membrane manufacturing method comprising: a third step which is a densification step of oxidizing, nitriding or carbonizing the second component. A method for producing a hydrogen permeable membrane according to claim 1,
The method for producing a hydrogen permeable membrane, wherein the metal base layer prepared in the first step includes the second component only in a limited region including the surface of the metal base layer. A method for producing a hydrogen permeable membrane according to claim 1 or 2,
In the second step, when forming the predetermined metal layer on the metal base layer in the second step, the second component is formed after forming at least a part of the predetermined metal layer. A method for producing a hydrogen permeable membrane, which is a step of oxidizing, nitriding or carbonizing the material. A method for producing a hydrogen permeable membrane that selectively permeates hydrogen,
(A) a first step of preparing a metal base layer containing a Group 5 metal;
(B) a second step of forming an intermediate layer containing a second component that can be oxidized, nitrided or carbonized on the metal base layer;
(C) a third step of forming a metal coating layer containing palladium (Pd) on the intermediate layer;
(D) A method for producing a hydrogen permeable membrane, comprising: a fourth step which is a densification step of oxidizing, nitriding or carbonizing the second component. A method for producing a hydrogen permeable membrane according to claim 4,
The intermediate layer formed in the second step further includes a refractory metal having a higher melting point than the metal base layer and the metal coating layer, in addition to the second component. A method for producing a hydrogen permeable membrane according to claim 5,
The second step is a step of forming the intermediate layer composed of a first layer disposed on the metal base layer side and a second layer disposed on the metal coating layer side,
The method for producing a hydrogen permeable membrane, wherein the first layer has a higher content of the refractory metal and a lower content of the second component than the second layer. A method for producing a hydrogen permeable membrane according to any one of claims 4 to 6,
The fourth step is a step of oxidizing, nitriding or carbonizing the second component after the third step. A method for producing a hydrogen permeable membrane according to any one of claims 1 to 7,
The second component is selected from chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe), copper (Cu), molybdenum (Mo), and zirconium (Zr). Element,
The densification step is a step of oxidizing the second component. A method for producing a hydrogen permeable membrane. A method for producing a hydrogen permeable membrane according to any one of claims 1 to 7,
The second component is an element that forms, together with the Group 5 metal, a composite oxide having a melting point higher than the melting point of the Group 5 metal oxide,
The densification step is a step of oxidizing the second component. A method for producing a hydrogen permeable membrane. A method for producing a hydrogen permeable membrane according to claim 9,
The second component is an element selected from chromium (Cr), magnesium (Mg), and calcium (Ca). A method for producing a hydrogen permeable membrane according to any one of claims 1 to 3,
The method for producing a hydrogen permeable membrane, wherein the second component is an element that is more easily oxidized than the Group 5 metal. A method for producing a hydrogen permeable membrane according to claim 11,
The second component includes aluminum (Al), silicon (Si), titanium (Ti), zirconium (Zr), tantalum (Ta), gadolinium (Gd), niobium (Nb), tungsten (W), cerium (Ce). ), Yttrium (Y), ytterbium (Yb), neodymium (Nd), and praseodymium (Pr). A method for producing a hydrogen permeable membrane according to any one of claims 1 to 7,
The second component is an element selected from chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe),
The densification step is a step of nitriding the second component. A method for producing a hydrogen permeable membrane. A method for producing a hydrogen permeable membrane according to any one of claims 1 to 3,
The method for producing a hydrogen permeable membrane, wherein the second component is an element that is more easily nitrided than the Group 5 metal. A method for producing a hydrogen permeable membrane according to claim 14,
The second component is an element selected from aluminum (Al), silicon (Si), titanium (Ti), zirconium (Zr), magnesium (Mg), calcium (Ca), and boron (B). A method for producing a membrane. A method for producing a hydrogen permeable membrane according to any one of claims 1 to 7,
The second component is an element selected from silicon (Si) and titanium (Ti),
The densification step is a step of carbonizing the second component. A method for producing a hydrogen permeable membrane. A method for producing a hydrogen permeable membrane according to any one of claims 1 to 3,
The method for producing a hydrogen permeable membrane, wherein the second component is an element that is more easily carbonized than the Group 5 metal. A method for producing a hydrogen permeable membrane according to claim 17,
The method for producing a hydrogen permeable film, wherein the second component is an element selected from chromium (Cr), titanium (Ti), zirconium (Zr), tantalum (Ta), and molybdenum (Mo). A method for producing a hydrogen permeable membrane that selectively permeates hydrogen,
(A) a first step of preparing a metal base layer containing a Group 5 metal, the metal base layer containing a second component which can be oxidized, nitrided or carbonized at least in a region including the surface of the metal base layer When,
(B) When forming a multilayer structure by sequentially forming a predetermined metal layer on the surface of the metal base layer containing the second element, the metal coating layer containing palladium (Pd) And a second step of forming on the surface of the multilayer structure. A method for producing a hydrogen permeable membrane that selectively permeates hydrogen,
(A) a first step of preparing a metal base layer containing a Group 5 metal;
(B) a second step of forming a middle-layer on the metal base layer,
(C) a third step of forming a metal coating layer containing palladium (Pd) on the intermediate layer;
With
The second step includes a layer having a crystal structure containing a second component that can be oxidized, nitrided, or carbonized together with a hydrogen permeable metal having a composition different from that of the metal base layer and the metal coating layer. A method for producing a hydrogen permeable membrane, which is a step of forming a layer . A method for producing a hydrogen permeable membrane according to claim 19 or 20,
The second component includes chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe), copper (Cu), molybdenum (Mo), zirconium (Zr), magnesium (Mg). ), Calcium (Ca), tantalum (Ta), gadolinium (Gd), niobium (Nb), tungsten (W), cerium (Ce), yttrium (Y), ytterbium (Yb), neodymium (Nd), praseodymium (Pr) ), A method for producing a hydrogen permeable membrane which is an element selected from boron (B). A hydrogen permeable membrane that selectively permeates hydrogen,
A hydrogen permeable membrane produced by the method according to claim 1. A hydrogen permeable membrane that selectively permeates hydrogen,
A metal base layer containing a Group 5 metal;
A metal coating layer provided on at least one surface of the hydrogen permeable membrane and comprising palladium (Pd);
A plurality of layers including
The metal base layer contains a second component that can be oxidized, nitrided or carbonized in a region including a contact surface with a layer adjacent to the metal base layer. A hydrogen permeable membrane that selectively permeates hydrogen,
A metal base layer containing a Group 5 metal;
A metal coating layer provided on at least one surface of the hydrogen permeable membrane and containing palladium (Pd);
A second component which is provided between the metal base layer and the metal coating layer and which can be oxidized, nitrided or carbonized together with a hydrogen permeable metal having a composition different from that of the metal base layer and the metal coating layer. And a hydrogen permeable membrane comprising an intermediate layer having a crystal structure . A hydrogen-permeable membrane according to claim 23 or 24 Symbol mounting,
The second component includes chromium (Cr), aluminum (Al), silicon (Si), titanium (Ti), iron (Fe), copper (Cu), molybdenum (Mo), zirconium (Zr), magnesium (Mg). ), Calcium (Ca), tantalum (Ta), gadolinium (Gd), niobium (Nb), tungsten (W), cerium (Ce), yttrium (Y), ytterbium (Yb), neodymium (Nd), praseodymium (Pr) ), A hydrogen permeable membrane which is an element selected from boron (B). A hydrogen permeable membrane that selectively permeates hydrogen,
A metal base layer containing a Group 5 metal;
A metal coating layer provided on at least one surface of the hydrogen permeable membrane and comprising palladium (Pd);
A plurality of layers including
The metal base layer includes an oxide, a nitride, or a carbide at a contact surface with a layer adjacent to the metal base layer. A hydrogen permeable membrane that selectively permeates hydrogen,
A metal base layer containing a Group 5 metal;
A metal coating layer provided on at least one surface of the hydrogen permeable membrane and comprising palladium (Pd);
Wherein an intermediate layer that is provided between the metal base layer and the metal coating layer, the contact surface of the layer disposed on the surface side of the intermediate layer adjacent to the intermediate layer, nitride compound, or hydrogen permeable membrane and an intermediate layer comprising a carbide. A hydrogen permeable membrane that selectively permeates hydrogen,
A metal base layer containing a Group 5 metal;
A metal coating layer provided on at least one surface of the hydrogen permeable membrane and comprising palladium (Pd);
An intermediate layer provided between the metal base layer and the metal coating layer, comprising a hydrogen permeable metal having a composition different from that of the metal base layer and the metal coating layer, and a second component and having a crystal structure And
The intermediate layer includes an oxide, nitride, or carbide containing the second component in a gap on the crystal structure in the intermediate layer.

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