JP2008034212A - Ionic conductor, energy device, and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ionic conductor with excellent ionic conductivity as well as excellent intensity even at a temperature higher than 100°C, and an energy device as well as a fuel cell equipped with the same. <P>SOLUTION: The ionic conductor is made by containing an organic porous body and an electrolyte material, of which, the former has holes in which the electrolyte material containing a cation component and an anion component is retained. It contains the organic porous body consisting of polyimide and ionic liquid, of which the former has holes in which the ionic liquid containing a cation component and an anion component is retained. The energy device is provided with the ionic conductor. The fuel cell is provided with the ionic conductor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ion conductor, an energy device, and a fuel cell. More specifically, the present invention relates to an ion conductor containing an organic porous material and an electrolyte material, and an energy device and a fuel cell including the ion conductor.

As an electrolyte membrane of a fuel cell, a cation-conductive or proton-conductive ceramic membrane infiltrated with an ionic liquid has been proposed (see Patent Document 1).
This membrane is obtained by modifying a porous and flexible ceramic membrane described in Patent Document 2 so as to exhibit ionic conductivity, and then treating it with an ionic liquid.
In addition, this membrane has extremely good proton conductivity or cation conductivity at a temperature higher than 100 ° C. by using an ionic liquid.
Furthermore, this membrane maintains flexibility and can be used as an electrolyte membrane for fuel cells.
JP-T-2004-515351 PCT / EP98 / 05939

  However, the conventional film in which such a ceramic film and an ionic liquid are combined has a problem that the strength is low because the ceramic is brittle.

  The present invention has been made in view of such problems of the prior art, and its object is to have excellent ion conductivity and excellent strength even at a temperature higher than 100 ° C. An ion conductor, an energy device including the ion conductor, and a fuel cell are provided.

  As a result of intensive studies to achieve the above object, the present inventors have found that the above object can be achieved by retaining an electrolyte material having excellent ion conductivity in the pores of the organic porous material. The invention has been completed.

  That is, the ionic conductor of the present invention comprises an organic porous material and an electrolyte material, and the organic porous material has pores and holds the electrolyte material in the pores. And a cation component and an anion component.

  The preferred embodiment of the ionic conductor of the present invention comprises an organic porous material and an electrolyte material, and the organic porous material has a spherical shape with a substantially uniform inner diameter, and the inside of the organic porous material. A plurality of holes arranged in a three-dimensional manner, and the spherical holes communicate with each other through a communication port formed between adjacent spherical holes, and the electrolyte material is contained in the spherical holes. The electrolyte material is characterized by containing a cation component and an anion component.

  Furthermore, another preferred embodiment of the ionic conductor of the present invention is characterized in that the electrolyte material is an ionic liquid.

  Moreover, the energy device of this invention is equipped with the said ion conductor of this invention, It is characterized by the above-mentioned.

  Furthermore, the fuel cell of the present invention is characterized by comprising the ionic conductor of the present invention.

  According to the present invention, an electrolyte material having excellent ionic conductivity is retained in the pores of the organic porous body, so that it has excellent ionic conductivity and excellent strength even at a temperature higher than 100 ° C. It is possible to provide an ion conductor having an energy device and a fuel cell including the ion conductor.

Hereinafter, the ion conductor of the present invention will be described in detail. In the present specification, “%” for the concentration, content and the like represents a mass percentage unless otherwise specified.
As described above, the ionic conductor of the present invention is an ionic conductor containing an organic porous material and an electrolyte material, and the organic porous material has pores and the electrolyte material in the pores. The electrolyte material contains a cation component and an anion component, and can be suitably used, for example, as an electrolyte membrane of a fuel cell.

Here, the ion conductor of this invention is demonstrated based on drawing.
FIG. 1 is a schematic view showing a cross-sectional structure of an embodiment of an ionic conductor according to the present invention. As shown in the figure, the ionic conductor 10 contains an organic porous body 12 and an electrolyte material 14. The organic porous body 12 holds the electrolyte material 14 in the holes 12a. Moreover, although not shown in figure, the electrolyte material 14 contains the cation component and the anion component. In addition, the code | symbol 20 of FIG. 1 shows the electrode arrange | positioned so that the said ion conductor 10 may be pinched | interposed as needed.
FIG. 2 is a scanning electron microscope (SEM) photograph of the organic porous body 12.

As described above, by holding the electrolyte material containing the cation component and the anion component in the pores of the organic porous body, the ion conductivity has high ion conductivity and excellent strength even at a temperature higher than 100 ° C. Become a body.
Moreover, since it can be comprised with a cheaper material than the conventional fluorine-type electrolyte, the secondary effect that the cheap ion conductor suitable for the spread is obtained is also acquired.

  In the present invention, as shown in FIG. 1, the plurality of holes 12a of the organic porous body 12 are spherical, the inner diameter of the spherical holes 12a is substantially uniform, and adjacent spherical holes 12a. It is preferable that they communicate with each other. In other words, it is desirable that spherical holes 12a exist three-dimensionally in the organic porous body 12, and the adjacent spherical holes 12a communicate with each other via a communication port. The electrolyte material 14 can be filled through the communication port formed between the spherical holes 12a.

Thus, by regularly holding the electrolyte material 14 inside the organic porous body 12, both materials are made into a composite, and the overall ionic conductivity can be further improved.
In a wet state, the organic porous body 12 suppresses the swelling of the electrolyte material 14. In particular, since the spherical pores 12a existing inside the organic porous body 12 are configured with a substantially uniform inner diameter, the organic pores 12 are homogeneously and dispersed with respect to swelling when the electrolyte material 14 is wet. Therefore, local damage of the ionic conductor 10 can be suppressed. In other words, the spherical pores 12a of the organic porous body 12 have a three-dimensional regular array structure, thereby supporting the electrolyte material 14 in a state in which the swelling pressure of the electrolyte material 14 is uniformly applied to the organic porous body 12. Can do.

  Furthermore, in the present invention, although not particularly limited, the porosity of the organic porous body 12 is preferably 70 to 90% by volume. When the porosity is less than 70% by volume, the filling rate of the electrolyte material 14 may be low and sufficient ionic conductivity may not be exhibited. Further, when the porosity exceeds 90% by volume, high strength may not be maintained.

  In the present invention, the organic porous body 12 is preferably made of polyimide, for example. This is because polyimide is excellent in heat resistance, mechanical strength, electrical characteristics, chemical resistance, and the like, and is desirable as a material constituting the organic porous film, but is not limited thereto. It is not a thing. That is, for example, polytetrafluoroethylene or polyetheretherketone can be used as long as the organic porous body has excellent performance such as heat resistance, mechanical strength, electrical characteristics, and chemical resistance. These can be used alone or copolymerized with polyimide or mixed.

Furthermore, in the present invention, when producing the organic porous body made of the polyimide, for example, various polyamic acids can be used as a raw material.
Thus, a desired organic porous body can be easily obtained by using a polyamic acid.

In the present invention, the electrolyte material 14 has excellent thermal stability (non-volatile, extremely low vapor pressure, flame retardancy, and high thermal decomposition temperature (250 to 400 ° C. or higher). From the viewpoint of having a low freezing point temperature (−20 ° C. or less) and being a liquid in a wide temperature range, etc.), a high ion density, a large heat capacity, and the like. It is.
In addition, for example, when the organic porous material is impregnated and held in the organic material, it is not necessary to dissolve the electrolytic material, and the process of forming the handling and the ion conductor can be simplified.
Note that the ionic liquid is a low melting point “salt” having an ionic conductivity, also called an ionic liquid or a room temperature molten salt, many of which are organic onium ions as cations and organic or inorganic anions as anions. The thing which shows the characteristic of the comparatively low melting point obtained by combining. These are expressed as “Ionic Liquid” in English, and recently there has been a movement to be unified with the name of “ionic liquid” among experts, so in this specification, it is unified with the name of ionic liquid. To do.

  Furthermore, in the present invention, as the cation component of the electrolyte material 14, an imidazolium derivative cation, a pyridinium derivative cation, a pyrrolidinium derivative cation, an ammonium derivative cation, a phosphonium derivative cation, a guanidinium derivative cation, an isouronium derivative cation or a thiourea derivative cation, and Mixtures according to these arbitrary combinations can be used.

  Examples of the imidazolium derivative cation include a 1-substituted imidazolium derivative cation represented by the following chemical formulas (1) to (3) (1), a 2-substituted imidazolium derivative cation (2), and a 3-substituted imidazolium. Derivative cations (3) and the like can be mentioned.

R in the above formula (1) represents an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, aralkyl group, acyl group, alkoxyalkyl group or heterocyclic group having 1 to 18 carbon atoms. .
Of these, those in which R is a methyl group, an ethyl group, a propyl group, an isopropyl group, or a butyl group can be preferably used.

At least one of R ¹ and R ^{2 in} the above formula (2) is an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, aralkyl group, acyl group, alkoxyalkyl having 1 to 18 carbon atoms. A group or a heterocyclic group;
Among these, in particular, at least one of R ¹ and R ² is a methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group, nonyl group, hexyl group, octyl group, decyl group, tetradecyl group, octadecyl group or What is a benzyl group can be used conveniently.

R ¹ , R ² and R ³ in the above formula (3) are each independently a hydrogen atom or an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group or aralkyl having 1 to 18 carbon atoms. A group, an acyl group, an alkoxyalkyl group or a heterocyclic group;
Among these, those in which R ¹ and R ² are methyl groups and R ³ is a hydrogen atom, or a methyl group, an ethyl group, a propyl group, a butyl group, or a hexyl group can be preferably used.

  As said pyridinium derivative cation, the pyridinium derivative cation represented by following Chemical formula (4) can be mentioned, for example.

R ¹ in the above formula (4) represents an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, aralkyl group, acyl group, alkoxyalkyl group or heterocyclic group having 1 to 18 carbon atoms. R ² , R ³ and R ⁴ are all hydrogen atoms, or at least one is a hydrogen atom, the remaining alkyl group having 1 to 18 carbon atoms, alkenyl group, alkynyl group, cycloalkyl group, aryl group, aralkyl A group, an acyl group, an alkoxyalkyl group or a heterocyclic group;
Among these, in particular, R ¹ is an ethyl group, butyl group, hexyl group or octyl group, and R ² , R ³ and R ⁴ are all hydrogen atoms, or one or two are methyl groups Can be suitably used.

  Examples of the pyrrolidinium derivative cation include a pyrrolidinium derivative cation represented by the following chemical formula (5).

At least one of R ¹ and R ^{2 in} the above formula (5) is an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, aralkyl group, acyl group, alkoxyalkyl having 1 to 18 carbon atoms. A group or a heterocyclic group;
Among these, those in which R ¹ and R ² are a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group or an octyl group can be preferably used. Furthermore, any one of R ¹ and R ² may be a hydrogen atom.

  As said ammonium derivative cation, the ammonium derivative cation represented by following Chemical formula (6) can be mentioned, for example.

R ¹ , R ² , R ³ and R ⁴ in the above formula (6) are each independently an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group or aralkyl having 1 to 18 carbon atoms. A group, an acyl group, an alkoxyalkyl group or a heterocyclic group;
Among these, in particular, all of R ¹ , R ² , R ³ and R ⁴ are methyl groups or butyl groups, and further, at least one or two are ethyl groups, butyl groups or methoxyethyl groups Can be suitably used.

  Examples of the phosphonium derivative cation include a phosphonium derivative cation represented by the following chemical formula (7).

R ¹ , R ² , R ³ and R ⁴ in the above formula (7) are each independently an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group or aralkyl having 1 to 18 carbon atoms. A group, an acyl group, an alkoxyalkyl group or a heterocyclic group;
Of these, those in which all of R ¹ , R ² , R ³ and R ⁴ are butyl groups, and those having a hexyl group and at least one tetradecyl group can be preferably used.

  Examples of the guanidinium derivative cation include guanidinium derivative cations represented by the following chemical formulas (8) to (10).

R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ in the above formula (8) are each independently a hydrogen atom or an alkyl group, alkenyl group or alkynyl group having 1 to 18 carbon atoms. , A cycloalkyl group, an aryl group, an aralkyl group, an acyl group, an alkoxyalkyl group or a heterocyclic group.
Among these, in particular, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are all hydrogen atoms, or R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ . Those in which any one of them is a methyl group, an isopropyl group or a phenyl group can be suitably used.

R ¹ , R ² , R ³ , R ⁴ and R ⁵ in the above formula (9) are each independently a hydrogen atom or an alkyl group, alkenyl group, alkynyl group or cycloalkyl group having 1 to 18 carbon atoms. A group, an aryl group, an aralkyl group, an acyl group, an alkoxyalkyl group or a heterocyclic group;
Among these, in particular, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are all methyl groups, or R ¹ , R ² , R ³ and R ⁴ are methyl groups, and R ⁵ is ethyl. What is group can be used conveniently.

R ¹ , R ² , R ³ , R ⁴ and R ⁵ in the above formula (10) are each independently a hydrogen atom or an alkyl group, alkenyl group, alkynyl group or cycloalkyl group having 1 to 18 carbon atoms. A group, an aryl group, an aralkyl group, an acyl group, an alkoxyalkyl group or a heterocyclic group;
Among these, those in which R ¹ , R ² , R ³ and R ⁴ are methyl groups and R ⁵ is an ethyl group can be preferably used.

  Furthermore, in the present invention, as the anion component of the electrolyte material 14, halogen anions, sulfate anions, sulfonates anions, amides anions, imides anions, methanes anions, borates anions, phosphates Mixtures based on anions or antimony anions and any combination thereof can be used.

Examples of the halogen anions include halogen anions represented by the following chemical formulas (11) to (13), Cl ⁻ (11), Br ⁻ (12), I ⁻ (13), and the like. Can do.

Examples of the sulfate anions and sulfonate anions include sulfate anions and sulfonate anions represented by the following chemical formulas (14) to (22), SO ₄ ²⁻ (14), HSO ₄ ⁻ (15), CH ₃ SO ₄ ⁻ (16), C ₂ H ₅ SO ₄ ⁻ (17), C ₄ H ₉ SO ₄ ⁻ (18), C ₆ H ₁₃ SO ₄ ⁻ (19) , C ₈ H ₁₇ SO ₄ ⁻ (20), CF ₃ SO ₃ ⁻ (21), and

And so on.

Furthermore, examples of the amide anion and imide anion include amide anions and imide anions represented by the following chemical formulas (23) to (25), (CN) ₂ N ⁻ (23), [N ( CF ₃ ) ₂ )] ⁻ (24) and [N (SO ₂ CF ₃ ) ₂ ] ⁻ (25).

Examples of the methane anions include methane anions represented by the following chemical formulas (26) and (27), [HC (SO ₂ CF ₃ ) ₂ ] ⁻ (26), and C (SO ₂ CF). ₃ ) ₃ ⁻ (27) and the like.

Further, as the borate anions, for example, borate anions represented by the following chemical formulas (28) to (34), BF ₄ ⁻ (28), B (CN) ₄ ⁻ (29),

And so on.

Examples of the phosphate anions include phosphate anions represented by the following chemical formulas (35) to (43), PO ₄ ³⁻ (35), HPO ₄ ²⁻ (36), (C ₂ F ₅ ) PO ₄ ⁻ (37), (C ₂ F ₅ ) ₂ P (O) O ⁻ (38), PF ₆ ⁻ (39), (C ₂ F ₅ ) ₃ PF ₃ ⁻ ( 40), (C ₃ F ₇ ) ₃ PF ₃ ⁻ (41), (C ₄ F ₉ ) ₃ PF ₃ ⁻ (42), and

And so on.

Furthermore, examples of the antimony anions include antimony anions represented by the following chemical formula (44), SbF ₆ ⁻ (44), and the like.

Furthermore, as anions of other salts, for example, anions of other salts represented by the following chemical formulas (45) to (47), C ₁₀ H ₂₁ COO ⁻ (45), CF ₃ COO ⁻ (46) ), And Co (CO) ₄ ⁻ (47).
In addition, it can use suitably also about the polyvalent anion represented by the said Formula (14), (35), and (36).
And the above-mentioned cation component and anion component can be used not only individually but also in an appropriate combination of two or more.

  Further, the electrode 20 is not particularly limited, but it is preferable that the electrode 20 includes a noble metal such as platinum and ruthenium, and an electrode catalyst component such as rhodium and glassy carbon. Such an electrode is desirably highly dispersed through a supporting substrate such as carbon paper, carbon black, or a mixture of these with polytetrafluoroethylene.

Here, an example of the manufacturing method of the ion conductor of this invention is demonstrated.
FIG. 3 is a process diagram showing an example of a procedure for producing a silica template. A silica template is produced by a process as shown in FIG. Specifically, first, a dispersion medium and a spherical silica particle suspension are prepared and mixed. Next, this mixed solution is filtered to form a film. Thereafter, the obtained filtration molded film is fired to obtain a silica template as schematically shown in the figure.

Here, the dispersion medium is not particularly limited, and for example, water or ethanol can be used.
Further, the spherical silica particles are not particularly limited. For example, particles having a diameter of 10 to 1000 nm can be suitably used. When the diameter is less than 10 nm, it is difficult to obtain particles having a uniform particle size distribution at low cost. On the other hand, when the diameter exceeds 1000 nm, the structure of the organic porous body is unlikely to be uniform.
Further, when the mixed solution is filtered, it is not particularly limited. However, it is preferable to perform the filtration while reducing the pressure so that the pressure is 10 kPa or less at the maximum with respect to the atmospheric pressure.
Furthermore, when firing the filtration molded membrane, although not particularly limited, for example, in order to sufficiently burn the silica, to heat-treat at least 800 ° C. for 30 minutes, to improve the mechanical strength The heat treatment may be performed at 900 ° C. or higher for 4 hours.

  FIG. 4 is a process diagram showing an example of a procedure for producing an organic porous body. An organic porous body is produced by a process as shown in FIG. Specifically, first, the silica template obtained above is immersed in a polyamic acid solution diluted with a solvent. Subsequently, it dries under reduced pressure and volatilizes a solvent. Furthermore, polyamic acid is heated and polymerized by heat treatment to form polyimide, and a composite film of polyimide and silica template is formed. Thereafter, the silica template is removed from the composite film to obtain an organic porous body made of polyimide.

Here, the solvent is not particularly limited as long as it can dissolve polyamic acid. For example, dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, m-cresol, and the like can be used. .
In addition, the polyamic acid has a structure of —C ₆ H ₄ —O—C ₆ H ₄ — (═R), but is not limited thereto. That is, those having the structure of R represented by the following chemical formulas (48) to (50) may be used.

Further, the degree of polymerization n is not particularly limited. For example, in the case of polyamic acid having the structure shown in FIG. 4, one having n = 2500-3500 can be used. In such a range, it is easy to obtain a desired organic porous material.
Further, when the polyamic acid is heated and polymerized, it is not particularly limited. For example, the polyamic acid may be heat-treated at about 300 ° C. for an appropriate time according to the amount of the polyamic acid.
Further, the polymerization degree n of the polyimide is not particularly limited. For example, n = 500 to 5000 is preferable. If n is less than 500, there may be a problem with the mechanical strength of the formed polyimide pores, and if it exceeds 5000, there is a possibility that it cannot be introduced into the voids of the template.
Furthermore, when removing the silica template from the composite film, it is not particularly limited, but for example, it may be treated with a hydrogen fluoride solution.

FIG. 5 is an explanatory view showing an example of the production procedure of the ion conductor. As shown in the figure, first, the organic porous body obtained above and an electrolyte material placed in a container are prepared, the organic porous body is immersed in the electrolyte material, the inside of the desiccator is decompressed, and the electrolyte is formed into the organic porous body. The material is impregnated to produce a composite ion conductor.
Here, as the electrolyte material, those containing the above-described cation component or anion component, preferably an ionic liquid containing the above-described cation component or anion component, can be used as appropriate.

Next, the energy device of the present invention will be described.
The energy device of the present invention is configured by applying the above-described ionic conductor of the present invention. In this case, it can be appropriately systemized by combining with other control means.
Typically, a fuel cell (single cell or stack structure), water electrolysis, hydrohalic acid electrolysis, salt electrolysis, oxygen concentrator, temperature sensor, gas sensor, and the like can be given.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to these Examples.

(Example 1-1)
<Preparation of silica template>
First, an operation as shown in FIG. 3 was performed to produce a membranous silica template. Specifically, 2 ml of colloidal silica containing spherical silica particles having an average diameter of 550 nm (silica particle content: 20.5%) and 30 ml of water as a dispersion medium are mixed to uniformly disperse the particles. Was stirred ultrasonically. Next, the membrane filter was set in a filter holder, and the pressure was reduced to 5 kPa or less with respect to atmospheric pressure using a manual vacuum pump, and the mixture was filtered. After all the mixed liquid has been filtered, the excess dispersion medium contained in the filter-formed membrane is removed using filter paper or the like as a water absorbing material, sufficiently dried at room temperature, and peeled off from the membrane filter to thereby remove spherical silica. A film in which the particles were three-dimensionally ordered was obtained.
The film thus obtained was heat-treated at 900 ° C. for 30 minutes, further heat-treated at 1100 ° C. for 4 hours, and slowly returned to room temperature to obtain the desired film-like silica template.
6 (a) and 6 (b) are SEM photographs of the (a) surface and (b) cross section of the obtained silica template.

<Preparation of polyimide porous membrane>
Next, an operation as shown in FIG. 4 was performed to produce a polyimide porous membrane. Specifically, the obtained silica template was immersed in a polyamic acid solution. Here, as the polyamic acid solution, a solution obtained by dissolving polyamic acid (degree of polymerization: 3000) so as to be 8% in dimethylacetamide as a solvent was used.
Subsequently, it dried under reduced pressure and the solvent was volatilized.
Furthermore, the polyamic acid was converted into polyimide by heat polymerization to form a composite film of silica template and polyimide. Here, the heat polymerization was performed by two-stage heat treatment at 200 ° C. for 1 hour and 320 ° C. for 1 hour.
Thereafter, the silica template is removed from the composite membrane with a 10% HF aqueous solution, and a polyimide porous membrane (3-Dimensionally Ordered Macroporous of Polyimide) in which spherical holes having a substantially uniform inner diameter are three-dimensionally regularly arranged. : 3DOM Polyimide).

<Impregnation of ionic liquid>
Next, an operation as shown in FIG. 5 was performed to produce an ion conductor. Specifically, the obtained polyimide porous membrane was immersed in butyl methyl imidazolium trifluorosulfonate imide (BMImTFSI) as an ionic liquid which is an example of an electrolyte material, and the pressure was reduced for 20 minutes to obtain the ion conduction of this example. Got the body.

(Example 1-2)
Except for using a polyimide porous membrane in which spherical holes having a substantially uniform inner diameter are regularly arranged three-dimensionally, a polyimide porous membrane in which pores are not regularly arranged in three dimensions is used. The same operation as 1-1 was repeated to obtain an ion conductor of this example.

[Performance evaluation]
(Ion conductivity test)
The ion conductivity of Example 1-1 and Example 1-2 was evaluated. The obtained results are shown in FIG.
In addition, FIG. 8 is a perspective explanatory view showing the point of the ion conductivity test. As shown in the figure, the ionic conductivity of each example was sandwiched between gold electrodes having a predetermined area (0.8 cm ² ), and the ionic conductivity was evaluated based on the impedance measured by applying an AC wave of 100 Hz to 100 kHz. .
The ionic conductivity here was calculated based on the area in contact with the gold electrode without considering the porosity. In the measurement, the ionic conductivity was measured by changing the temperature.

  7 that Example 1-1 and Example 1-2 belonging to the scope of the present invention have excellent ionic conductivity even at a temperature higher than 100 ° C.

(Example 2-1)
FIG. 9 is a schematic cross-sectional view showing a basic configuration of a fuel cell to which the ion conductor of the present invention is applied.
As shown in the figure, the fuel cell uses an ionic conductor 10 composed of an organic porous body 12 holding an electrolyte material 14 as an electrolyte membrane, and the electrolyte membrane is sandwiched between a pair of electrodes 20. It is configured to be sandwiched between separators 30.
The electrode 20 includes an electrode catalyst layer 22 and a gas diffusion layer 24.
Here, the polyimide porous membrane obtained in Example 1-1 was used as the organic porous material, BMImTFSI was used as the electrolyte material, platinum-supported carbon was used as the electrode catalyst layer, carbon paper was used as the gas diffusion layer, and the separator. As for each, the carbon plate was used.

Each electrode 20 is formed with a gas flow path 30a by a separator 30 so that hydrogen (or a fuel gas containing hydrogen) and oxygen (or an oxidizing gas containing oxygen) can be supplied.
In addition, as for an electrode, the side which supplies fuel gas becomes an anode, and the side which supplies oxidizing gas becomes a cathode.

During power generation by this fuel cell, each gas is supplied from the gas flow path through the gas diffusion layer to the electrode catalyst layer, and the following electrochemical reaction proceeds.
H ₂ → 2H ⁺ + 2e ⁻ (I)
2H ⁺ + 2e ⁻ + (1/2) O ₂ → H ₂ O (II)
H ₂ + (1/2) O ₂ → H ₂ O (III)

Formula (I) shows the reaction on the cathode side of the fuel cell, and Formula (II) shows the reaction on the anode side of the fuel cell. Further, the formula (III) is a reaction performed in the entire fuel cell. These reactions proceed in the electrode catalyst layer.
Thus, the fuel cell to which the ion conductor is applied can directly convert the chemical energy of the fuel into electric energy, and can be expected to have high energy conversion efficiency.
Specifically, the fuel cell can be operated in the middle temperature range (about 120 ° C.), the radiator load can be reduced compared to the conventional polymer electrolyte fuel cell, and the radiator size can be reduced. it can. As a result, the system capacity can be reduced and the system weight can be reduced. Furthermore, since polyimide is one of the constituent materials of the ion conductor, an inexpensive ion conductor with high chemical resistance and stretchability can be obtained.

It is the schematic which shows the cross-section of one Embodiment of the ion conductor of this invention. It is a SEM photograph of an example of an organic porous body. It is process drawing which shows an example of a preparation procedure of a silica template. It is process drawing which shows an example of the preparation procedure of an organic porous body. It is explanatory drawing which shows an example of the preparation procedure of an ion conductor. (A) And (b) is the SEM photograph of the (a) surface and (b) cross section of the silica template obtained in Example 1-1. It is a graph which shows the change of the ionic conductivity with respect to the temperature in the ion conductor of Example 1-1 and Example 1-2. It is a perspective explanatory view showing the point of an ion conductivity test. It is a schematic sectional drawing which shows the structural example of the fuel cell to which the ion conductor of this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ion conductor 12 Organic porous body 12a Hole 14 Electrolyte material 20 Electrode 22 Electrode catalyst layer 24 Gas diffusion layer 30 Separator 30a Gas flow path

Claims (10)

An ionic conductor comprising an organic porous material and an electrolyte material,
The organic porous body has pores, holds the electrolyte material in the pores,
The electrolyte material includes a cation component and an anion component.   The organic porous body has a spherical shape with a substantially uniform inner diameter, and has a plurality of holes arranged three-dimensionally inside the organic porous body, and the spherical holes are adjacent to adjacent spherical holes. The ionic conductor according to claim 1, wherein the ionic conductors communicate with each other through a communication port formed on the surface.   3. The ion conductor according to claim 1, wherein the organic porous body has a porosity of 70 to 90% by volume.   The ionic conductor according to claim 1, wherein the organic porous body is made of polyimide.   The ionic conductor according to claim 4, wherein a raw material of the polyimide is polyamic acid.   The ionic conductor according to any one of claims 1 to 5, wherein the electrolyte material is an ionic liquid.   The cation component contains at least one selected from the group consisting of imidazolium derivative cations, pyridinium derivative cations, pyrrolidinium derivative cations, ammonium derivative cations, phosphonium derivative cations, guanidinium derivative cations, isouronium derivative cations and thiourea derivative cations. The ionic conductor according to any one of claims 1 to 6, wherein:   The anion component was selected from the group consisting of a halogen anion, a sulfate anion, a sulfonate anion, an amide anion, an imide anion, a methane anion, a borate anion, a phosphate anion, and an antimony anion. The ionic conductor according to claim 1, comprising at least one kind.   An energy device comprising the ionic conductor according to any one of claims 1 to 8.   A fuel cell comprising the ion conductor according to any one of claims 1 to 8.

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