JP2010280512A - INORGANIC ORGANIC COMPOSITE MATERIAL, PROCESS FOR PRODUCING INORGANIC ORGANIC COMPOSITE MATERIAL, PRODUCT USING INORGANIC ORGANIC COMPOSITE - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inorganic / organic composite material capable of obtaining a stable charge separation state with a longer life than a conventional inorganic / organic composite material.
[Solution]
An inorganic-organic composite material is produced by, for example, immersing the aluminum-substituted mesoporous silica in a solution of the electron donor / acceptor linked molecule or a salt thereof. An example is shown in FIG. The inorganic-organic composite material of the present invention can be used for photocatalysts, photosensitizers, dyes, oxidizing agents, reducing agents, batteries, dye-sensitized solar cells, organic EL devices, and any other applications.
[Selection] Figure 1

Description

  The present invention relates to an inorganic-organic composite material, a method for producing an inorganic-organic composite material, and a product using the inorganic-organic composite material.

  Electron donor / acceptor linking molecules are used in, for example, studies of photosynthesis models. As electron donor / acceptor linking molecules, many dye molecules such as porphyrins have been reported, and their charge separation state (electron transfer state) has been reported. From the viewpoint of industrial applicability, these electron donor / acceptor linking molecules are required to have characteristics such as long life of charge separation state, strong oxidizing power, strong reducing power, etc. Research has been repeated for improvement.

  Among these properties, the long life of the charge separation state is an important factor. This is because the characteristics in the charge separation state cannot be sufficiently utilized if the lifetime of the charge separation state is extremely short. For example, 9-mesityl-10-methylacridinium ion (see Patent Document 1, Non-Patent Documents 1 and 2) has been reported as an electron donor / acceptor linking molecule that can provide a long-lived charge separation state. Yes. However, such an electron donor / acceptor linked molecule is deactivated by reverse electron transfer between molecules even if a long-lived charge separation state is obtained by light irradiation. In order to prevent this deactivation, it is necessary to freeze the solvent at a low temperature. For this reason, it is difficult for conventional electron donor / acceptor linked molecules to use the charge separation state in solution, which has been a problem in industrial use.

  Accordingly, the present inventors have invented an inorganic-organic composite material formed from zeolite and a quinolinium ion derivative (analog) that is an electron donor / acceptor linking molecule. According to this inorganic-organic composite material, it is possible to obtain a stable charge separation state with a much longer life as compared with conventional electron donor / acceptor linking molecules (Non-patent Document 3). However, if a stable charge separation state with a longer lifetime can be obtained, the utility value of the charge separation state is further increased in industrial fields utilizing electron transfer, such as oxidants and reducing agents. It is considered to be.

JP 2005-145853 A S. Fukuzumi, H. Kotani, K. Ohkubo, S. Ogo, N. V. Tkachenko, H. Lemmetyinen, J. Am. Chem. Soc., 2004, 126, 1600 K. Ohkubo, H. Kotani, S. Fukuzumi, Chem. Commun. 2005, 4520. Proceedings of the 87th Annual Meeting of the Chemical Society of Japan CD-ROM, 2E4-41

  Accordingly, an object of the present invention is to provide an inorganic-organic composite material that can provide a stable charge separation state with a longer life than conventional inorganic-organic composite materials. Furthermore, this invention provides the manufacturing method of the said inorganic organic composite material, and the product using the said inorganic organic composite material.

  As a result of intensive studies in order to solve the above problems, the present inventors have found that, as an inorganic substance, aluminum having a structure in which a part of silicon (Si) atoms in mesoporous silica is substituted with aluminum (Al) atoms. It has been found that substituted mesoporous silica is used.

That is, the inorganic-organic composite material of the present invention is
An inorganic-organic composite material formed from an inorganic material and an organic material,
The inorganic substance is aluminum-substituted mesoporous silica having a structure in which a part of silicon (Si) atoms of mesoporous silica is substituted with aluminum (Al) atoms,
The organic substance is an organic substance formed from an electron donor / acceptor linked molecule in which an electron donor site and an electron acceptor site are linked or a salt thereof.

  The production method of the present invention is a method for producing the inorganic-organic composite material of the present invention, and includes a dipping step of immersing the aluminum-substituted mesoporous silica in the solution of the electron donor / acceptor linked molecule or a salt thereof. It is a manufacturing method.

  The product of the present invention is a product containing the inorganic-organic composite material of the present invention and used as a photocatalyst, a photosensitizer, a dye, an oxidizing agent, a reducing agent, a battery, a dye-sensitized solar cell, or an organic EL element. . That is, the photocatalyst, photosensitizer, dye, oxidizing agent, reducing agent, battery, dye-sensitized solar cell, or organic EL element of the present invention each contains the inorganic-organic composite material of the present invention.

  The inorganic / organic composite material of the present invention is formed from the aluminum-substituted mesoporous silica and the electron donor / acceptor linking molecule or a salt thereof, and thus has a longer life and stability than the conventional inorganic / organic composite material. Charge separation state can be obtained. For this reason, the inorganic-organic composite material of the present invention can fully utilize the characteristics of the charge-separated state of the electron donor-acceptor linked molecule, such as a photocatalyst, a photosensitizer, a dye, an oxidizing agent, It can be used for various products such as reducing agents, batteries, dye-sensitized solar cells, and organic EL devices. For example, a hydrogen generation photocatalyst can be obtained by combining the inorganic-organic composite material of the present invention with a platinum catalyst. Moreover, the battery of this invention can also be used as a dye-sensitized solar cell by including the inorganic-organic composite material of this invention as a pigment | dye. Furthermore, the use of the inorganic-organic composite material of the present invention is not limited to these, and can be used for any use. Moreover, the inorganic-organic composite material of the present invention can be easily and efficiently produced by the production method of the present invention. However, the method for producing the inorganic-organic composite material of the present invention is not limited to this, and any production method may be used.

  Next, an embodiment of the present invention will be described. However, the present invention is not limited to the following description.

[1. Inorganic organic composite material]
First, the inorganic-organic composite material of the present invention will be described.

  When an inorganic-organic composite material is formed from a porous material (inorganic material) and an electron donor / acceptor linking molecule (organic material), a longer-lived charge separation state can be obtained than the electron donor / acceptor linking molecule alone. Cheap. The reason for this is not necessarily clear, but is considered as follows, for example. However, the following description is an example of a mechanism that can be estimated, and the present invention is not limited to this consideration.

  That is, the electron donor / acceptor linking molecule is excited by, for example, light irradiation in a solution to generate a charge separation state. However, when two or more molecules in the charge separation state are present close to each other, they are easily returned to the original state by the electron transfer reaction between the molecules and deactivated. That is, the life of the charge separation state is short and its characteristics cannot be fully utilized.

  For example, the electron donor / acceptor linked molecule has a structure in which the electron donor / acceptor linked molecule is inserted into the pores of the porous material, so that the charge separated state molecules of the electron donor / acceptor linked molecule are isolated from each other. It is considered that the intermolecular electron transfer reaction can be suppressed. Thereby, the high reactivity of a charge separation state can be utilized efficiently.

  Next, in the inorganic-organic composite material of the present invention, the following mechanism can be considered as a mechanism that can obtain a charge separation state that is longer in life and more stable than the conventional inorganic-organic composite material. However, the following description is only an example of a mechanism that can be estimated, and does not limit or limit the present invention.

That is, mesoporous silica has a relatively large pore size. Therefore, an electron donor / acceptor linking molecule having a large molecular size can also be inserted into the pore. In general, an electron donor / acceptor linked molecule with a large molecular size is less than the electron donor / acceptor linked molecule with a small molecular size because the rearrangement energy associated with electron transfer is small and the reverse electron transfer reaction in the molecule is suppressed. It is possible to achieve a long-life charge separation state. Thereby, the inorganic-organic composite material of the present invention can obtain a charge separation state that is longer in life and more stable than conventional inorganic-organic composite materials. According to the inorganic-organic composite material of the present invention, for example, it is possible to obtain a long-lived charge separation state at room temperature or higher. The lifetime of the charge-separated state of the inorganic-organic composite material of the present invention is not particularly limited. For example, at 25 ° C. (298 K) in a vacuum, for example, 1 second or longer, preferably 1 × 10 ² seconds or longer, more preferably 5 × 10 5 ^Although it is ² seconds or more and the upper limit is not particularly limited, it is, for example, 1 × 10 ⁴ seconds or less. The lifetime of the charge-separated state of the inorganic-organic composite material of the present invention is, for example, 1 × 10 ⁻¹ seconds or more, preferably 10 seconds or more, more preferably 1 × 10 ² seconds at 100 ° C. (373 K) in vacuum. The upper limit value is not particularly limited but is, for example, 5 × 10 ³ seconds or less.

  As described above, the inorganic-organic composite material of the present invention is formed from aluminum-substituted mesoporous silica (inorganic material) and an electron donor / acceptor linked molecule or a salt thereof (organic material). Hereinafter, the aluminum-substituted mesoporous silica and the electron donor / acceptor linking molecule will be described.

[1-1. Aluminum-substituted mesoporous silica (inorganic material)]
Mesoporous silica refers to silica gel having mesopores, that is, pores having a relatively large pore size. In the present invention, aluminum-substituted mesoporous silica refers to an inorganic substance having a structure in which a part of silicon (Si) atoms in mesoporous silica is substituted with aluminum (Al) atoms. The aluminum-substituted mesoporous silica in the inorganic-organic composite material of the present invention may or may not contain elements other than Si, Al and O. In the present invention, elements other than Si, Al, and O that may be contained in the aluminum-substituted mesoporous silica are not particularly limited. For example, hydrogen (H), alkali metals (Li, Na, K, Rb, Cs And Fr), halogens (F, Cl, Br, I, and At), transition metals (eg, Fe, Cu, Mn), and the like.

The pore of the aluminum-substituted mesoporous silica in the inorganic-organic composite material of the present invention, that is, the pore size of “mesopore” is not particularly limited, but for example, is as follows. That is, first, the magnification of TEM (transmission electron microscope, manufactured by Hitachi, Ltd., trade name HITACHI Model H-800 transmission electron microscope) is set to 5 × 10 ⁵ times, and the surface of the aluminum-substituted mesoporous silica is 1 μm. Observe in a square area on all sides. Of all the mesopores observed in the square region, both the major axis (maximum diameter) L _max (nm) and the minor axis (minimum diameter) L _min (nm) are within a certain numerical range. Is at least 80% of the number of all observed mesopores. The certain numerical range is, for example, 2 to 50 nm, preferably 2 to 10 nm, and more preferably 2 to 4 nm. However, the measurement method is an example of a method for measuring the mesopore pore diameter of the aluminum-substituted mesoporous silica, and the aluminum-substituted mesoporous silica in the inorganic-organic composite material of the present invention is not limited to that measured by this measurement method. .

  The aluminum-substituted mesoporous silica in the inorganic-organic composite material of the present invention is a material having a structure in which a part of silicon (Si) atoms of mesoporous silica, that is, a material having silicon dioxide as a basic skeleton is substituted with aluminum (Al) atoms. Therefore, it can be said that it is a kind of zeolite. In a narrow sense, “zeolite” is a substance having a structure in which a part of silicon (Si) atoms of a substance having silicon dioxide as a basic skeleton is substituted with aluminum (Al) atoms, and the size of pores is small. It may refer to a substance of about 2.0 nm or less (for example, 0.5 to 2.0 nm). However, in the present invention, zeolite means all substances having a structure in which a part of silicon (Si) atoms of a substance having silicon dioxide as a basic skeleton is substituted with aluminum (Al) atoms.

  The aluminum-substituted mesoporous silica in the inorganic-organic composite material of the present invention is not particularly limited, and for example, known aluminum-substituted mesoporous silica can be appropriately used. In the present invention, the aluminum-substituted mesoporous silica may be appropriately synthesized (manufactured) and may be a commercially available product. The production method for synthesis (production) is not particularly limited. For example, it can be produced by a sol-gel method using a surfactant as a template. By changing the type of the surfactant, the pore size, shape, and filling The structure can be controlled. More specifically, for example, as follows. That is, first, an aqueous solution of an aluminum compound (for example, triisopropoxyaluminum) and an alkali (for example, sodium hydroxide) is prepared in an inert gas atmosphere. In this aqueous solution, a surfactant is dissolved at a concentration equal to or higher than the critical micelle concentration, and micelle particles having a certain size and structure are formed according to the type of the surfactant. When left standing for a while, the micelle particles take a packed structure and become a colloidal crystal. Further, tetraethoxysilane or the like serving as a silica source is added to this solution, and a sol-gel reaction is advanced in the gap between the colloidal crystals to form an aluminum-substituted mesoporous silica skeleton. After completion of the reaction, the obtained aluminum-substituted mesoporous silica is fired at a high temperature, and the surfactant used as a template is decomposed and removed to obtain pure aluminum-substituted mesoporous silica. In this way, the aluminum-substituted mesoporous silica used in the present invention can be obtained.

In the aluminum-substituted mesoporous silica synthesis reaction, the reaction temperature is not particularly limited. For example, the reaction may be performed in water at room temperature (5-35 ° C.), and the reaction is performed in hot water (100 ° C. water). The reaction may be performed at an appropriate temperature therebetween. The reaction time is not particularly limited and may be set as appropriate. Further, as the surfactant, for example, by using a small molecule cationic surfactant, aluminum-substituted mesoporous silica corresponding to MCM series (for example, MCM-41 type) mesoporous silica can be produced. Furthermore, by using, for example, a block copolymer as the surfactant, aluminum-substituted mesoporous silica corresponding to SBA series (for example, SBA-15 type) mesoporous silica can be produced. The aluminum-substituted mesoporous silica synthesis reaction can be appropriately performed with reference to, for example, the following documents (1) to (4).
(1) Kresge, CT; Leonowicz, ME; Roth, WJ; Vartuli, JC; Beck, JS Nature 1992, 359, 710-712
(2) Beck, JS et al J. Am. Chem. Soc. 1992, 114, 10834
(3) Corma, A .; Kumar, D. Stud. Surf. Sci. Catal. 1998, 117, 201
(4) Janicke, MT et al. J. Am. Chem. Soc. 1998, 120, 6940-6951.

  In the inorganic-organic composite material of the present invention, the aluminum-substituted mesoporous silica is not particularly limited as described above, but for example, MCM-41 type, MCM-48 type, MCM-50 type, SBA-15 type, or FSM-16 Aluminum-substituted mesoporous silica having a structure in which part of silicon (Si) atoms of the type mesoporous silica is substituted with aluminum (Al) atoms is preferable. Among these, aluminum-substituted mesoporous silica (AlMCM-41) having a structure in which part of silicon (Si) atoms of MCM-41 type mesoporous silica is substituted with aluminum (Al) atoms is particularly preferable. In the present invention, the pore diameter of mesopores in AlMCM-41 is not particularly limited, but is, for example, 2 to 10 nm.

  The structure of the inorganic-organic composite material of the present invention is not particularly limited. For example, as described above, the structure in which the electron donor-acceptor linking molecule is inserted into the pores of the aluminum-substituted mesoporous silica is used. It is preferable to have. When the electron donor / acceptor linking molecule is inserted and immobilized in the pores by ion exchange, it does not easily desorb and becomes a stable structure, making full use of characteristics such as high reactivity in the charge separation state. This is because it is considered possible. However, this description also does not limit the present invention.

[1-2. Electron donor / acceptor linking molecule or salt thereof (organic substance)]
Next, the organic substance will be described. In the inorganic-organic composite material of the present invention, the organic material is not particularly limited except that it is formed from an electron donor / acceptor linking molecule or a salt thereof.

  The electron donor / acceptor linking molecule is preferably a cationic molecule, for example. That is, in the aluminum-substituted mesoporous silica (inorganic substance), a part of the silicon (Si) atoms of the silicon dioxide skeleton is substituted with aluminum (Al) atoms, so that the aluminum atoms are acid sites (negatively charged portions). ) As a result, the aluminum-substituted mesoporous silica (inorganic substance) is negatively charged throughout the skeleton, and cations (for example, alkali metal ions such as Li, Na, K, etc., and other arbitrary metals are present in the pores (mesopores). Ions) and the like are incorporated. When the electron donor / acceptor linked molecule, which is a cationic molecule, is added thereto, a cation exchange reaction between the cation in the pore and the electron donor / acceptor linked molecule occurs. Thereby, the inorganic-organic composite material of the present invention in which the electron donor / acceptor linking molecule is incorporated into the pores of the aluminum-substituted mesoporous silica can be formed. However, this description is also an example, and does not limit the present invention.

In the organic substance, for example,
The electron donor site is one or more electron donor groups;
More preferably, the electron acceptor site is one or more aromatic cations. In this case, the aromatic cation may be a single ring or a condensed ring, and the aromatic ring may or may not contain a hetero atom, and may have a substituent other than the electron donating group. It does not have to have. The number of atoms constituting the aromatic ring forming the aromatic cation is not particularly limited, but a 5-26 membered ring is more preferable.

  Specific examples of the aromatic ring forming the aromatic cation include, for example, a pyrrolium ring, a pyridinium ring, a quinolinium ring, an isoquinolinium ring, an acridinium ring, a 3,4-benzoquinolinium ring, and a 5,6-benzoquinolinium. Nium ring, 6,7-benzoquinolinium ring, 7,8-benzoquinolinium ring, 3,4-benzoisoquinolinium ring, 5,6-benzoisoquinolinium ring, 6,7-benzo At least one selected from the group consisting of an isoquinolinium ring, a 7,8-benzoisoquinolinium ring, and a ring in which at least one of carbon atoms constituting the ring is substituted with a heteroatom. More preferably it is. If it is a macrocyclic (high π electron number) aromatic cation such as an acridinium ring, a benzoquinolinium ring, or a benzoisoquinolinium ring, for example, the absorption band shifts to the longer wavelength side and enters the visible light region. By having absorption, visible light excitation may also be possible.

More specifically, the electron donor / acceptor linking molecule is, for example, from the group consisting of a compound represented by any one of the following formulas (1) to (8), a stereoisomer and a tautomer thereof. There is at least one selected.
In the above formulas (1) to (8),
R is a hydrogen atom or an arbitrary substituent,
Ar is the electron donating group and may be one or plural, and in the case of plural, they may be the same or different,
The aromatic ring that forms the aromatic cation may or may not have one or more arbitrary substituents other than R and Ar.

In the formulas (1) to (8), R is a hydrogen atom, an alkyl group, a benzyl group, a carboxyalkyl group (an alkyl group having a carboxyl group added to the terminal), an aminoalkyl group (an alkyl having an amino group added to the terminal) Group) or a polyether chain. R is a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a benzyl group, a linear or branched alkyl group having 1 to 6 carbon atoms with a carboxyl group added to the terminal, and an amino group added to the terminal. It is more preferably a linear or branched alkyl group having 1 to 6 carbon atoms or a polyethylene glycol (PEG) chain. The PEG chain is an example of the polyether chain, but the type of the polyether chain is not limited to this, and any polyether chain may be used. In R ¹ , the degree of polymerization of the polyether chain is not particularly limited, but is, for example, 1 to 100, preferably 1 to 50, and more preferably 1 to 10. When the polyether chain is a PEG chain, the degree of polymerization is not particularly limited, but is, for example, 1 to 100, preferably 1 to 50, and more preferably 1 to 10.

  In the electron donor / acceptor linking molecule, the electron donating group (for example, Ar in the formulas (1) to (8)) is at least one selected from the group consisting of a hydrogen atom, an alkyl group, and an aromatic ring. It is preferable that In this case, the aromatic ring may further have one or a plurality of substituents on the ring, the substituents may be the same or different in a plurality of cases, and the electron donating group is in a plurality of cases. May be the same or different. In this case, in the electron donating group, the alkyl group is more preferably a linear or branched alkyl group having 1 to 6 carbon atoms. Further, in the electron donating group (for example, Ar in the formulas (1) to (8)), the aromatic ring is formed from a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a pyridine ring, a thiophene ring, and a pyrene ring. More preferably, it is at least one selected from the group consisting of: In the electron donating group (for example, Ar in the formulas (1) to (8)), the substituent on the aromatic ring includes an alkyl group, an alkoxy group, a primary to tertiary amine, a carboxylic acid, and a carboxylic acid. More preferably, it is at least one selected from the group consisting of acid esters. In Ar, the substituent on the aromatic ring is a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a primary to tertiary amine, or a carvone. More preferably, it is at least one selected from the group consisting of an acid and a carboxylic acid ester. In the substituent on the aromatic ring, “carboxylic acid” refers to a carboxyl group or a group to which a carboxyl group is added (for example, a carboxyalkyl group), and “carboxylic acid ester” refers to an alkoxycarbonyl group, A carboxylic acid ester group such as a phenoxycarbonyl group, and an acyloxy group. The alkyl group in the carboxyalkyl group is preferably, for example, a linear or branched alkyl group having 1 to 6 carbon atoms, and the alkoxy group in the alkoxycarbonyl group is, for example, a linear chain having 1 to 6 carbon atoms. Or a branched alkoxy group is preferable.

  The electron donating group (for example, Ar in the formulas (1) to (8)) is, for example, a phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 2,3-dimethylphenyl group, 2 , 4-dimethylphenyl group, 2,5-dimethylphenyl group, 2,6-dimethylphenyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, 2,3,4-trimethylphenyl group, 2 , 3,5-trimethylphenyl group, 2,3,6-trimethylphenyl group, mesityl group (2,4,6-trimethylphenyl group), and 3,4,5-trimethylphenyl group More preferably, it is at least one.

More specifically, the electron donor / acceptor linking molecule is selected from the group consisting of, for example, a 9-substituted acridinium ion represented by the following formula (9), a tautomer and a stereoisomer thereof: More preferred is at least one of
In said Formula (9), R and Ar are the same as said Formula (1).

As the electron donor / acceptor linking molecule, for example, 9-mesityl-10-methylacridinium ion represented by the following formula (10) is particularly preferable.

  In the inorganic-organic composite material of the present invention, the electron donor / acceptor linking molecule has an isomer such as a tautomer or a stereoisomer (eg, geometric isomer, conformer isomer and optical isomer). In any case, any isomer can be used in the present invention. The salt of the electron donor / acceptor linking molecule may be an acid addition salt, but may be a base addition salt when the electron donor / acceptor linking molecule can form a base addition salt. Furthermore, the acid forming the acid addition salt may be an inorganic acid or an organic acid, and the base forming the base addition salt may be an inorganic base or an organic base. The inorganic acid is not particularly limited. For example, sulfuric acid, phosphoric acid, hydrofluoric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, hypofluorite, hypochlorous acid, hypobromite, Hypoarousous acid, fluorinated acid, chlorous acid, bromic acid, iodic acid, fluoric acid, chloric acid, bromic acid, iodic acid, perfluoric acid, perchloric acid, perbromic acid, periodic acid, etc. Can be given. The organic acid is not particularly limited, and examples thereof include p-toluenesulfonic acid, methanesulfonic acid, oxalic acid, p-bromobenzenesulfonic acid, carbonic acid, succinic acid, citric acid, benzoic acid, and acetic acid. The inorganic base is not particularly limited, and examples thereof include ammonium hydroxide, alkali metal hydroxides, alkaline earth metal hydroxides, carbonates and hydrogen carbonates, and more specifically, for example, Examples thereof include sodium hydroxide, potassium hydroxide, potassium carbonate, sodium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, calcium hydroxide and calcium carbonate. The organic base is not particularly limited, and examples thereof include ethanolamine, triethylamine, and tris (hydroxymethyl) aminomethane. The method for producing these salts is not particularly limited, and for example, the salt can be produced by a method such as appropriately adding the acid or base as described above to the electron donor / acceptor linking molecule by a known method. Further, when an isomer exists in a substituent or the like, any isomer may be used. For example, in the case of “naphthyl group”, it may be a 1-naphthyl group or a 2-naphthyl group.

  In the inorganic-organic composite material of the present invention, the absorption band of the electron donor / acceptor linking molecule is not particularly limited, but preferably has an absorption band in the visible light region. This is because by having an absorption band in the visible light region, the inorganic-organic composite material of the present invention can be excited with visible light. According to this, since sunlight can be used as an energy source, for example, application to a solar cell or the like is also possible.

  In the present invention, the alkyl group is not particularly limited, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. The same applies to groups containing an alkyl group in the structure (alkylamino group, alkoxy group, etc.). Further, the perfluoroalkyl group is not particularly limited, but is derived from, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. The same applies to groups containing a perfluoroalkyl group in the structure (perfluoroalkylsulfonyl group, perfluoroacyl group, etc.). In the present invention, the acyl group is not particularly limited. For example, formyl group, acetyl group, propionyl group, isobutyryl group, valeryl group, isovaleryl group, pivaloyl group, hexanoyl group, cyclohexanoyl group, benzoyl group, ethoxycarbonyl The same applies to groups containing an acyl group in the structure (acyloxy group, alkanoyloxy group, etc.). In the present invention, the carbon number of the acyl group includes carbonyl carbon. For example, an alkanoyl group having 1 carbon atom (acyl group) refers to a formyl group. Furthermore, in the present invention, “halogen” refers to any halogen element, and examples thereof include fluorine, chlorine, bromine and iodine.

In the inorganic-organic composite material of the present invention, the organic material (electron donor / acceptor linking molecule) may be a commercially available product, or may be produced (synthesized) as appropriate. In the case of production, the production method is not particularly limited, and for example, it can be suitably produced by a known production method or referring to a known production method. As an example, the electron donor / acceptor linking molecule represented by the formula (9) can be produced, for example, by the Grignard reaction of acridone or its derivative (11) as described below. In the following formulas (11) and (12), R and Ar are the same as those in the formula (9). The reaction conditions (reaction temperature, reaction time, solvent, etc.) are not particularly limited, and may be appropriately set with reference to a known Grignard reaction.

  For example, in the case of 9-mesityl-10-methylacridinium ion represented by the following formula (10), a commercially available product may be used, but it can also be produced as follows. That is, first, the inside of a sufficiently dried reaction vessel is replaced with argon to obtain an argon atmosphere at normal temperature and pressure. In that atmosphere, 2.0 g (10 mmol) of mesitylene bromide (commercial reagent), 250 mg (10 mmol) of magnesium (commercial reagent) and 5 mL of dehydrated tetrahydrofuran are stirred to prepare a Grignard reagent. Thereto is added 50 mL of a dehydrated dichloromethane solution of 1.0 g (4.8 mmol) of 10-methylacridone (commercial reagent) and stirred for 12 hours. The product is hydrolyzed with water, aqueous perchloric acid is added and extracted with dichloromethane. The extract is recrystallized from methanol / dimethyl ether to give 9-mesityl-10-methylacridinium perchlorate. In addition, this manufacturing method is described in the said patent document 1 (Unexamined-Japanese-Patent No. 2005-145853).

[2. Manufacturing method of inorganic-organic composite material]
Although the manufacturing method of the inorganic-organic composite material of the present invention is not particularly limited as described above, it can be manufactured by the manufacturing method of the present invention. As described above, the production method of the present invention includes an immersion step in which the aluminum-substituted mesoporous silica is immersed in a solution of the electron donor / acceptor linked molecule or a salt thereof. Hereinafter, the production method of the present invention will be described in more detail.

  The production method of the present invention can be performed, for example, as follows. That is, first, the aluminum-substituted mesoporous silica is pretreated by firing. In the production method of the present invention, this pretreatment step may or may not be present, but it is preferable to include this step. When the aluminum-substituted mesoporous silica (zeolite) is fired, water molecules in the pores are removed, and electron donor / acceptor linked molecules are easily inserted, and the activity of the inorganic-organic composite material of the present invention is increased. It is possible. However, the present invention is not limited at all by this consideration.

  Although the calcination temperature in the said pre-processing process is not specifically limited, For example, it is 100-400 degreeC, Preferably it is 150-350 degreeC, More preferably, it is 200-300 degreeC. The firing time is not particularly limited, but is, for example, 2 to 24 hours, preferably 5 to 15 hours, and more preferably 8 to 12 hours. The atmosphere at the time of firing is not particularly limited, and may be, for example, in the air, but may be an inert gas atmosphere, reduced pressure, or the like. There are no particular limitations on the firing method, and for example, an appliance usually used for firing zeolite, such as an electric furnace or a dryer (dryer), can be used as appropriate. In addition, the kind of aluminum substituted mesoporous silica which can be used is not specifically limited, For example, it is as above-mentioned.

Next, the dipping step is performed in which the aluminum-substituted mesoporous silica is dipped in a solution of the electron donor / acceptor linked molecule or a salt thereof. In this step, the aluminum-substituted mesoporous silica may be simply immersed in a solution of the electron donor / acceptor linking molecule or a salt thereof, but if the solution is stirred, the formation rate of a composite material, etc. It is preferable from the viewpoint. In the solution, the solvent is not particularly limited, and may be used alone or in combination of two or more. However, a highly polar solvent is preferable from the viewpoint of the solubility of the electron donor / acceptor linking molecule or a salt thereof. More specifically, the solvent is preferably at least one selected from the group consisting of nitriles, halogenated solvents, ethers, amides, sulfoxides, ketones, alcohols, and water. The nitrile is not particularly limited, and examples thereof include acetonitrile, benzonitrile, butyronitrile, and the like. The halogenated solvent is not particularly limited, and examples thereof include chloroform and dichloromethane. The ether is not particularly limited, and examples thereof include THF (tetrahydrofuran). The amide is not particularly limited, and examples thereof include DMF (dimethylformamide). The sulfoxide is not particularly limited, and examples thereof include DMSO (dimethyl sulfoxide). Although the said ketone is not specifically limited, For example, acetone etc. are mentioned. Although the said alcohol is not specifically limited, For example, methanol etc. are mentioned. Of these solvents, acetonitrile is particularly preferred. In the solution, the concentration of the electron donor / acceptor linking molecule is not particularly limited, but is, for example, 1.25 × 10 ^{−5 to} 1.50 × 10 ⁻⁴ mol / L, preferably 5.0 × 10 ^{−. 5 to} 1.50 × 10 ⁻⁴ mol / L, particularly preferably 1.0 × 10 ^{−4 to} 1.25 × 10 ⁻⁴ mol / L. In the solution, the amount (mole number) of the electron donor / acceptor linking molecule or salt thereof is not particularly limited, but is, for example, 2.5 × 10 ^{−5 to} 3 per 1 g of the aluminum-substituted mesoporous silica. 0.0 × 10 ⁻⁴ mol, preferably 1.0 × 10 ^{−4 to} 2.9 × 10 ⁻⁴ mol, and more preferably 2.0 × 10 ^{−4 to} 2.5 × 10 ⁻⁴ mol. In this immersion step, the temperature of the solution is not particularly limited, but is, for example, 0 to 45 ° C, preferably 15 to 40 ° C, more preferably 20 to 30 ° C, and particularly preferably 20 to 25 ° C. For example, it is simple and preferable to perform the immersion step at room temperature without particularly heating or cooling the solution. Although the immersion time is not particularly limited, for example, it is 1 to 48 hours, preferably 3 to 48 hours, more preferably 8 to 36 hours, and particularly preferably 12 to 24 hours.

  Further, an isolation step is performed in which the inorganic-organic composite material is collected by filtration, washed, and dried. This isolation step is not particularly limited, and may be omitted if not necessary. The cleaning solvent is not particularly limited, and for example, the same solvent as that used in the immersion step can be used. Although a drying temperature is not specifically limited, For example, it is 15-60 degreeC, Preferably it is 20-50 degreeC, More preferably, it is 25-40 degreeC. The atmosphere during drying is not particularly limited, and may be, for example, in the air or in an inert gas atmosphere. Further, drying may be performed under normal pressure conditions, but drying under reduced pressure is preferable from the viewpoint of drying speed.

[3. Product of the present invention]
Next, the product of the present invention and the method of using the same will be described.

  The inorganic-organic composite material of the present invention is used as it is as the product of the present invention, that is, the photocatalyst, photosensitizer, dye, oxidizing agent, reducing agent, battery, dye-sensitized solar cell, or organic EL device of the present invention. However, it may be used together with other appropriate substances. The products of the present invention, ie, photocatalysts, photosensitizers, dyes, oxidants, reducing agents, batteries, dye-sensitized solar cells, and organic EL devices, generate charge-separated states of the electron donor / acceptor linked molecules. Therefore, the excellent function can be exhibited. That is, the electron donor / acceptor linking molecule is generated between the electron donor / acceptor linking molecule, or between the electron donor / acceptor linking molecule and another substance by, for example, generating the charge separation state. It is possible to cause electron transfer between the two. As a result, the inorganic-organic composite material of the present invention can be suitably used for applications related to electron transfer between molecules or between materials, that is, the aforementioned oxidizing agent, reducing agent, battery, and the like. Further, as described above, the inorganic-organic composite material of the present invention is such that the electron donor / acceptor linking molecule or a salt thereof forms a composite material together with the aluminum-substituted mesoporous silica. The charge-separated state of the body-linked molecule has a long life, and its characteristics such as high reactivity are easy to use. The inorganic-organic composite material of the present invention can perform an electron transfer reduction reaction by transferring electrons from an electron donor / acceptor linked molecule charge-separated state to an electron acceptor material such as viologen. Moreover, the substance (reducible substance) that can be reduced by the reducing agent of the present invention is not limited to the electron acceptor substance such as viologen. The reducing agent of the present invention can be used for reduction reactions of various substances. Although it does not specifically limit as said to-be-reduced substance, For example, quinones, nitrobenzene, cyanobenzene, etc. are mentioned.

  The organic EL element of the present invention is as follows, for example. First, as an example of the structure of a general organic EL element, a transparent electrode (anode), an organic light emitting layer, and a metal electrode (cathode) are laminated in this order on a transparent substrate. The organic light emitting layer contains a light emitting material. In such an organic EL element, holes and electrons are injected into the organic light emitting layer by applying a voltage to the anode and the cathode. The energy generated by the recombination of the holes and electrons excites the luminescent material. Then, when the excited luminescent material returns to the ground state, light is emitted. The organic EL device of the present invention may be, for example, an organic EL device containing the inorganic-organic composite material of the present invention as the light emitting material. According to this configuration, for example, the electron donor / acceptor linking molecule is excited to generate a charge separation state, and further emits light by returning from the excitation state (charge separation state) to the ground state. In addition, the organic EL element of this invention is not limited at all by this description.

  In the product of the present invention containing the inorganic-organic composite material of the present invention, the method for generating the charge-separated state of the electron donor / acceptor linked molecule is not particularly limited. For example, photoexcitation is preferable, and visible light excitation is simpler. It is particularly preferable because it exists. In order to perform visible light excitation, as described above, it is preferable that the electron donor / acceptor linking molecule has an absorption band in the visible light region. Thereby, it is also possible to easily generate a charge separation state having both a long life, a high oxidizing power and a high reducing power.

  The inorganic-organic composite material of the present invention is a photocatalyst, photosensitizer by causing the electron donor / acceptor linked molecule to generate a charge separation state by photoexcitation and causing electron transfer between molecules or materials as described above. Etc. can be used. For example, as described above, a hydrogen generation photocatalyst can be obtained by combining the inorganic-organic composite material of the present invention with a platinum catalyst. Furthermore, the inorganic-organic composite material of the present invention can be used as a dye when the electron donor / acceptor linking molecule has an absorption band in the visible light region. For example, as described above, the battery of the present invention can be used as a dye-sensitized solar cell by including the inorganic-organic composite material of the present invention as a dye.

The method for photoexciting the electron donor / acceptor linked molecule is not particularly limited. For example, the inorganic organic composite material of the present invention may be immersed in a suitable solvent and then irradiated with light. Although it does not specifically limit as a solvent, For example, water or an organic solvent may be sufficient. Examples of the organic solvent include nitriles such as benzonitrile, acetonitrile and butyronitrile, halogenated solvents such as chloroform and dichloromethane, ethers such as THF (tetrahydrofuran), amides such as DMF (dimethylformamide), DMSO (dimethylsulfoxide) and the like. Sulfoxides, ketones such as acetone, alcohols such as methanol, and the like. These solvents may be used alone or in combination of two or more. The solvent is preferably a highly polar solvent from the viewpoint of the solubility of the electron donor / acceptor linking molecule, the stability of the excited state, and the like, and for example, acetonitrile is particularly preferable from the viewpoint of solubility. The amount of inorganic-organic composite material of the present invention is not particularly limited, it may be suitably adjusted as needed, the concentration of the electron donor-acceptor linked molecules, relative to the solvent, for example 5 × 10 ^{- 5} M or more, preferably 1 × 10 ⁻⁴ to 1 × 10 ⁻³ M.

  Moreover, although excitation light is not specifically limited, For example, visible light is preferable. In particular, if visible light contained in natural light such as sunlight is used, it can be easily excited. Among the wavelengths of visible light to be irradiated, a more preferable wavelength depends on an absorption band of the electron donor / acceptor linking molecule, but is preferably, for example, 300 to 450 nm, and more preferably 350 to 450 nm. Although the temperature at the time of irradiation with visible light is not particularly limited, for example, the reaction (excitation) can proceed at a room temperature of about 10 to 30 ° C.

  In order to use the inorganic-organic composite material of the present invention as a reducing agent, for example, the electron donor / acceptor linking molecule is excited by light irradiation to generate an excited species in an electron transfer state (charge separation state), Electrons are transferred from the excited species to the substance to be reduced to reduce the substance to be reduced. In order to use the inorganic-organic composite material of the present invention as an oxidizing agent, for example, the electron donor / acceptor linking molecule is excited by light irradiation to generate an excited species in an electron transfer state (charge separation state). Then, electrons are transferred from the oxidizable substance to the excited species to oxidize the oxidizable substance. These details are not particularly limited. For example, the step of generating the excited species by light irradiation may be performed by irradiating with light after immersing the inorganic-organic composite material of the present invention in a solvent as described above. Alternatively, the substance to be reduced or the substance to be oxidized may be dissolved in the solution in advance and irradiated with light. Various conditions such as the solvent used, the solution concentration, the irradiation light wavelength, and the temperature in these cases are not particularly limited, but are as described above, for example. The reduction step or the oxidation step is not particularly limited. For example, in the reducing agent of the present invention, the reduction step may be performed by automatically causing electron transfer from the excited species to the substance to be reduced after the solution is irradiated with light. Similarly, in the oxidizing agent of the present invention, the oxidation step may be performed by automatically causing electron transfer from the oxidizable substance to the excited species after light irradiation to the solution.

  In the reducing agent of the present invention, the substance to be reduced is not particularly limited, and examples thereof include quinones, nitrobenzenes, and cyanobenzenes. The substance amount ratio (molar ratio) between the electron donor / acceptor linking molecule and the substance to be reduced is not particularly limited, and is appropriately selected according to the type of the electron donor / acceptor linking molecule and the substance to be reduced. Although possible, for example, 1: 0.001-1: 1000, preferably 1: 0.005-1: 100, more preferably 1: 0.01-1: 10, particularly preferably 1: 0.1. 1: 1.

  In the oxidizing agent of the present invention, the substance to be oxidized is not particularly limited, and examples thereof include alkylbenzenes, alkylnaphthalenes, alkylanthracenes, and NADH analogs. The substance amount ratio (molar ratio) between the electron donor / acceptor linked molecule and the oxidizable substance is not particularly limited, and is appropriately selected according to the kind of the electron donor / acceptor linked molecule and the oxidizable substance. Although possible, for example, 1: 0.001-1: 1000, preferably 1: 0.005-1: 100, more preferably 1: 0.01-1: 10, particularly preferably 1: 0.1. 1: 1.

  In addition, for example, in the inorganic-organic composite material of the present invention, the reaction substrate can be incorporated in a size-selective manner as long as the pore diameter of the aluminum-substituted mesoporous silica is uniform. Accordingly, when the inorganic-organic composite material of the present invention is used as a photocatalyst, for example, it is possible to perform a position-selective reaction or a structure-selective reaction that is difficult in a homogeneous reaction. For example, if the electron donor / acceptor linking molecule has absorption in the visible light region, a charge separation state can be generated by visible light, so that sunlight can be used effectively. Further, by supporting metal or metal oxide fine particles as a co-catalyst on the aluminum-substituted mesoporous silica, the redox power of the electron donor / acceptor linked molecule can be used to generate hydrogen or water. Various photocatalytic reactions such as decomposition can also be performed. Since the aluminum-substituted mesoporous silica such as AlMCM-41 has a relatively large pore size, it is easy to support the promoter. In addition, the inorganic-organic composite material of the present invention can be used as a photocatalyst or the like at a high temperature by forming a long-lived and stable charge separation state at a high temperature (for example, 100 ° C.), for example. Can withstand the use of Furthermore, in the photocatalyst of the present invention, since the electron donor / acceptor linking molecule is immobilized on the aluminum-substituted mesoporous silica to form a composite material, when the electron donor / acceptor linking molecule is used alone. Unlike the photocatalyst, it can be easily separated and recovered from the reaction solution after use as a photocatalyst, so that it can be used as a recyclable photocatalyst. However, these descriptions are merely examples and do not limit the present invention.

  Furthermore, the use and usage method of the inorganic-organic composite material of the present invention are not limited to the above description, and all uses and usage methods are possible.

  Next, examples of the present invention will be described, but the present invention is not limited to the following examples. The theoretical considerations such as reaction mechanisms described in the following examples are merely examples of mechanisms that can be estimated, and do not limit the present invention.

  In the following, the absorbance (ultraviolet visible absorption spectrum) of the solution was measured using an instrument 8453 photodiode array spectrophotometer (trade name) manufactured by Hewlett-Packard. The ultraviolet-visible absorption spectrum by diffuse reflection spectroscopy was measured using Shimadzu UV-3300PC (trade name) manufactured by Shimadzu Corporation and ISR-3100 (trade name) of the company as its accessory device. XRD was measured by graphite-monochromatized Cu Ka radiation at room temperature using RINT-1100 (trade name) manufactured by Rigaku Corporation. The ESR spectrum was measured in a quartz ESR tube (inner diameter: 4.5 mm) using an X-band spectrometer (trade name: JES-RE1XE) manufactured by JEOL. USH-1005D (trade name, wavelength λ> 390 nm, output 1000 W) manufactured by USHIO INC. Was used as the high pressure mercury lamp. As the xenon lamp, Ushio Optical ModelX SX-UID 500XAMQ (trade name, wavelength λ> 390 nm, output 500 W) manufactured by USHIO INC. Was used. All chemicals are reagent grade and purchased from Tokyo Kasei, Wako Pure Chemicals, and Aldrich.

  In this example, 9-mesityl-10-methylacridinium ion, which is a cationic electron donor / acceptor (donor-acceptor, DA) -linked molecule, is ion-exchanged to form Na-substituted AlMCM-41 mesoporous. An inorganic-organic composite material was prepared by inserting into silica. Further, the photo-charge separation of the inorganic-organic composite material was examined, and it was confirmed that the charge separation state (electron transfer state) was long-lived and stable and suitable for products such as an oxidizing agent, a reducing agent, and a photocatalyst.

[Synthesis of Na-substituted AlMCM-41 mesoporous silica]
Na-substituted AlMCM-41 mesoporous silica was synthesized as described below with reference to Janicke, MT et al. J. Am. Chem. Soc. 1998, 120, 6940-6951. That is, first, 0.472 g of Al (OiPr) ₃ , 39.2 g of deionized water and 5.00 g of 2M NaOHaq were placed in an eggplant flask in an inert gas (N ₂ or Ar) atmosphere at 25 ° C. (298 K) for 1 hour. Stir. Next, 0.80 g of cetyltrimethylammonium bromide (CTAB) and 3.85 g of tetraethoxysilane (TEOS) were added thereto, and the mixture was further stirred at 25 ° C. (298 K) for 16 hours. The obtained solid was collected by filtration, washed with water, heated to 500 ° C. at 2 ° C./min in an inert gas (N ₂ or Ar) stream, and further heated at 500 ° C. for 6 hours. Thereafter, when cooled to room temperature at 2 ° C./min, a black powder was obtained. This black powder was heated to 500 ° C. at 2 ° C./min in an inert gas (N ₂ or Ar) stream, and further heated at 500 ° C. for 6 hours. Thereafter, when cooled to room temperature at 2 ° C./min, the target product, AlMCM-41 (Na-substituted), was obtained as a white powder. Further, the reaction was carried out in the same manner except that the water at 25 ° C. (298 K) was changed to hot water at 100 ° C. (373 K), and the target product, AlMCM-41 (Na-substituted), was obtained as a white powder. It was.

  It was confirmed by XRD that the white powder was the target product. The result is shown in the spectrum diagram of FIG. In the figure, the horizontal axis indicates 2θ. FIG. 3 is an XRD pattern of the white powder synthesized in water at 25 ° C. (298 K), and FIG. 4 is an XRD pattern document of AlMCM-41 (Tuel, A. et al. Chem. Mater. 2004, 16 , 2969-2974.) Indicates the value. The left side of FIG. 4 shows the XRD pattern of [Ca], [Cs], [K], and [Na] AlMCM-41 from the top before firing and the right after firing, respectively. As shown in the figure, the peak value in the XRD pattern was in good agreement with the literature value, and thus it was confirmed that the white powder was the target AlMCM-41.

[Example 1]
As shown in FIG. 1, an inorganic-organic composite material of the present invention formed from AlMCM-41 type aluminum-substituted mesoporous silica (zeolite) and 9-mesityl-10-methylacridinium ion was produced. In addition, FIG. 1 is a schematic diagram, and the wordings, numerical values, and the like in the drawing are merely examples of the presumable molecular structure, reaction mechanism, and the like, and AlMCM-41 type zeolite, 9-mesityl-10 in this example. -Methyl acridinium ion, inorganic-organic composite material, etc. are not limited at all. Note that 1Å is equal to 0.1 nm, that is, 10 ⁻¹⁰ m.

That is, as described above, 0.25 g of Na-substituted AlMCM-41 type zeolite synthesized and pre-fired in water at 25 ° C. (298 K) was added to 9-mesityl-10-methylacridinium perchlorate (Tokyo Chemical Industry Co., Ltd.). Company) 4 × 10 ⁻³ mol / L acetonitrile solution (25 mL) was added and stirred at room temperature for 12 hours to obtain a yellowish green suspension. This suspension is a suspension of an inorganic-organic composite material formed from the AlMCM-41 zeolite and 9-mesityl-10-methylacridinium ion in acetonitrile. FIG. 5 shows an ultraviolet-visible absorption spectrum of the perchlorate 9-mesityl-10-methylacridinium (9-mesityl-10-methylacridinium ion, Acr ⁺ -Mes) acetonitrile solution before the reaction and after the reaction. The diffuse reflection spectrum of the suspension of the inorganic organic composite material (Acr ⁺ -Mes @ AlMCM-41) is also shown. In the figure, the vertical axis represents absorbance and the horizontal axis represents wavelength (nm). The broken line is the spectrum of the perchlorate 9-mesityl-10-methylacridinium (9-mesityl-10-methylacridinium ion, Acr ⁺ -Mes) acetonitrile solution before reaction, and the solid line is after reaction. It is the spectrum of the said inorganic organic composite material (Acr ^<+ >-Mes @ AlMCM-41) suspension. As shown in the figure, the maximum absorption wavelength λ _max was about 360 nm before and after the reaction, but the diffuse reflection spectrum of the suspension after the reaction (yellow green) showed the perchlorate 9- before the reaction. The mesityl-10-methylacridinium acetonitrile solution and Na-substituted AlMCM-41 type zeolite (colorless, not absorbing in the visible light region) showed different patterns. From this, it was confirmed that an inorganic-organic composite material formed from AlMCM-41 type zeolite and 9-mesityl-10-methylacridinium ion was generated. In addition, since 9-mesityl-10-methylacridinium ion has a relatively large pore diameter (mesopore) of about 2 to 4 nm of the AlMCM-41 type zeolite, cation exchange with Na ⁺ ion causes AlMCM-41. It is estimated that it is inserted into the pores of the type zeolite.

Furthermore, except that the perchlorate 9-mesityl-10-methylacridinium acetonitrile solution concentration was variously changed, an inorganic-organic composite material was produced in the same manner, and 9-mesityl-10-methyl remaining in the acetonitrile solution was produced. From the amount of acridinium ions, the amount of 9-mesityl-10-methylacridinium ions inserted into the AlMCM-41 type zeolite was calculated (10 ⁻⁵ mol / g). The results are shown in the graph of FIG. In the figure, the horizontal axis is the perchlorate 9-mesityl-10-methylacridinium acetonitrile solution concentration (mM), and the vertical axis is 9-mesityl-10-methylacridini for AlMCM-41 type zeolite. It is the insertion amount (10 ^<-5 > mol / g) of um ion. As shown in the figure, it was confirmed that 9-mesityl-10-methylacridinium ion can be inserted into AlMCM-41 type zeolite at a maximum (saturation amount) of 1.1 × 10 ⁻⁴ mol. When the Na-substituted AlMCM-41 type zeolite was changed to Y type zeolite (GL Science Co., Ltd., trade name SK40), as shown in FIG. 2, 9-mesityl-10-methylacridinium ion was changed to Y type zeolite. It was not inserted into the pores at all. This is presumably because the pore size of the Y-type zeolite is as small as about 0.7 nm.

  Further, the inorganic-organic composite material was filtered off from the acetonitrile suspension and isolated by drying at 25 ° C. for 5 hours using a vacuum line. Then, it was confirmed that the inorganic-organic composite material was not altered by a method such as resuspending in acetonitrile and measuring a diffuse reflection spectrum. That is, it was confirmed that 9-mesityl-10-methylacridinium ion was immobilized on the AlMCM-41 type zeolite in the inorganic-organic composite material and was not easily separated (desorbed).

[Evaluation of charge separation state]
The inorganic organic composite material (Acr ⁺ -Mes @ AlMCM-41) obtained in Example 1 has a long and stable charge separation state (electron transfer state), and products such as an oxidant, a reducing agent, and a photocatalyst. Confirmed that it is suitable for. As the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41), among those obtained in Example 1, 9-mesityl-10-methylacridinium ion (Acr ⁺ -Mes) was added to the AlMCM-41 type zeolite. In contrast, the maximum (saturation amount) of 1.1 × 10 ⁻⁴ mol inserted was isolated and used.

That is, first, the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41) is irradiated with visible light for 5 seconds in a high vacuum at 25 ° C. (298 K) with a high-pressure mercury lamp (wavelength λ> 390 nm). When the ESR spectrum was measured, a signal indicating the presence of a radical was confirmed. This ESR signal is considered to originate from the charge separation state (Acr ^· −Mes ^{· +} ) generated by intramolecular electron transfer from the Mes site to the Acr ⁺ site in the singlet excited state. That is, in the AlMCM-41 zeolite, as shown below, a charge separation state (Acr ^· −Mes ^{· +} ) of 9-mesityl-10-methylacridinium ion (Acr ⁺ -Mes) is generated, and the inorganic-organic composite material It was confirmed that (Acr ⁺ -Mes @ AlMCM-41) was in a charge separation state (Acr ^· -Mes ^{· +} @ AlMCM-41). FIG. 6 shows the ESR spectrum diagram. From the decay of the ESR signal, the charge separation state (Acr ^· −Mes ^{· +} @ AlMCM-41) of the inorganic organic composite material (Acr ⁺ -Mes @ AlMCM-41) is at 25 ° C. (298 K) in a high vacuum. It was confirmed to be long and stable for about 500 seconds.

Next, the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41) was irradiated with visible light for 30 seconds in a high vacuum at 100 ° C. (373 K) with a high-pressure mercury lamp (wavelength λ> 390 nm). Thereafter, when the ESR spectrum was measured in the same manner, a signal indicating the presence of a radical was confirmed. This ESR signal is considered to originate from the charge separation state (Acr ^· −Mes ^{· +} ) generated by intramolecular electron transfer from the Mes site to the Acr ⁺ site in the singlet excited state. That is, as in the case of 25 ° C. (298 K), in AlMCM-41 zeolite, as shown below, the charge separation state of 9-mesityl-10-methylacridinium ion (Acr ⁺ -Mes) (Acr ^· −Mes ^{· +} ) Was formed, and it was confirmed that the inorganic organic composite material (Acr ⁺ -Mes @ AlMCM-41) was in a charge separation state (Acr ^· −Mes ^{· +} @ AlMCM-41). FIG. 7 shows the ESR spectrum diagram. Further, the graph of FIG. 8 shows the attenuation of the ESR signal of FIG. In the figure, the horizontal axis represents the elapsed time (seconds) after the end of light irradiation, and the vertical axis represents the ESR signal intensity (I). The inset in FIG. 8 shows the elapsed time (seconds) after the end of light irradiation on the horizontal axis, and ln (I / I ₀ ) (I ₀ is the elapsed time after the end of light irradiation is zero ( It is a graph which shows the ESR intensity | strength immediately after light irradiation). As shown in the figure, the decay of this ESR signal followed the first-order kinetic equation (observation constant k _obs = 1.1 × 10 ⁻² S ⁻¹ ). The decay of the ESR signal is considered to be caused by Acr ^· −Mes ^{· +} returning to Acr ⁺ −Mes again by an intramolecular reverse electron transfer reaction. From this decay rate, in the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41), the charge-separated state (Acr ^· −Mes ^{· +} ) of the electron donor / acceptor linked molecule incorporated in the AlMCM-41 zeolite. However, it was confirmed that it has a very long charge separation lifetime of about 10 seconds in spite of a very high temperature of 100 ° C.

As described above, the inorganic-organic composite material of Example 1 (Acr ⁺ -Mes @ AlMCM-41) has a long-life and stable charge separation state at both a room temperature of 25 ° C. (298 K) and a high temperature of 100 ° C. (373 K). showed that. This indicates that the inorganic-organic composite material of Example 1 (Acr ⁺ -Mes @ AlMCM-41) exhibits high redox ability and is suitable for use as an oxidizing agent and a reducing agent. In addition, showing such a long-life and stable charge separation state by irradiation with visible light indicates that it is suitable as a photocatalyst. As described above, there is no example in the prior art in which the charge separation state generation and the reaction dynamics of the electron donor-acceptor linked molecule can be spectroscopically observed by “visible light irradiation” at “high temperature above room temperature”. . In particular, the generation of a charge separation state having a long lifetime even at a high temperature of 100 ° C. is an extremely excellent effect of the present invention.

Furthermore, after the ESR signal decays, irradiate the high-pressure mercury lamp again in the same manner as described above, stop the irradiation when the ESR signal reaches the maximum value, and after the ESR signal decays, repeat the high-pressure mercury lamp again under the same conditions. It was. The graph of FIG. 9 shows the ESR signal intensity diagram at that time. In the figure, the horizontal axis represents elapsed time, and the vertical axis represents ESR intensity (I). As shown in the figure, the maximum value of the ESR signal hardly decreased even when the light irradiation (ON) and the light irradiation stop (OFF) were repeated many times. This means that the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41) of Example 1 is not deteriorated by repeated photoexcitation and can withstand repeated use as an oxidizing agent, a reducing agent, a photocatalyst, and the like. Show.

Furthermore, the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41) of Example 1 was irradiated with light for 300 seconds at 25 ° C. (298 K) in a high vacuum using a high-pressure mercury lamp (wavelength λ> 390 nm). The ultraviolet-visible absorption spectrum (diffuse reflection spectrum) of the solid was measured before and after the light irradiation. The spectrum diagram is shown in the graph of FIG. In the figure, the horizontal axis is wavelength (nm) and the vertical axis is absorbance. As shown in the figure, the absorption band near 500 nm increased after light irradiation. This is considered to be originated from the Acr ^· radical charge-separated state (Acr ^· -Mes ^{· +)} produced by the light irradiation to the Acr ⁺ -Mes inserted into AlMCM-41 zeolite. As a result of visual confirmation, the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41), which was yellowish green before light irradiation, turned orange after light irradiation. Thus, in the inorganic-organic composite material of the present invention, when at least one of the electron donor / acceptor linking molecule and its charge separation state has an absorption band peculiar to the visible light region, charge separation is also caused by color change. You can check the status generation. Thereby, for example, when used for an oxidizing agent, a reducing agent, a photocatalyst, etc., there is an advantage that the progress of the reaction can be easily confirmed.

Furthermore, when the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41) of Example 1 was irradiated with light at 100 ° C. (373 K) for 10 seconds using a xenon lamp, a solid ultraviolet-visible material was obtained as described above. In the absorption spectrum (diffuse reflection spectrum), the absorption band near 500 nm increased. In the graph of FIG. 11, the attenuation curve of the diffuse reflection spectrum is shown together with the attenuation curve of the ESR signal. FIG. 11A is a diffuse reflection spectrum attenuation curve, where the horizontal axis represents the elapsed time after light irradiation (seconds), and the vertical axis represents the absorbance (ΔAbs) at a wavelength of 500 nm. In addition, the inset in FIG. 11A is a graph in which the horizontal axis indicates the elapsed time (seconds) after the end of light irradiation, and the vertical axis indicates lnΔAbs. As shown in the figure, the attenuation of the diffuse reflection spectrum followed a first-order kinetic equation (observation constant k _obs = 1.0 × 10 ⁻² S ⁻¹ ). FIG. 11B is a graph showing an ESR signal attenuation curve after a high-pressure mercury lamp at 100 ° C. (373 K), which is exactly the same as FIG. As shown in FIGS. 11A and 11B ^, the decay rate of the ESR signal intensity coincided with the decay rate of the absorption band derived from Acr ^{· at} 500 nm. This is a result further supporting that the inorganic / organic composite material (Acr ⁺ -Mes @ AlMCM-41) of Example 1 has a long life and stability even at a high temperature of 100 ° C.

As described above, in the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41) of Example 1, the inserted electron donor / acceptor linked molecule could be quantified by various spectroscopic observations. When this inorganic organic composite material was irradiated with light, it was not only long and stable at room temperature, but also a stable charge separation state with a very long life of about 10 seconds even at a high temperature of 100 ° C. This charge separation state could be spectroscopically observed by ESR and diffuse reflection spectroscopy.

  Further, it was confirmed that the inorganic-organic composite material of Example 1 was photoexcited in a solvent such as acetonitrile and used as an oxidizing agent, a reducing agent or a photocatalyst.

  As described above, according to the inorganic-organic composite material of the present invention, a stable charge separation state with a longer life than the conventional inorganic-organic composite material can be obtained. For this reason, the inorganic-organic composite material of the present invention can fully utilize the characteristics of the charge-separated state of the electron donor / acceptor linking molecule, and it can be used as a photocatalyst, photosensitizer, dye, oxidizing agent, reducing agent. It can be used for various products such as an agent, a battery, a dye-sensitized solar cell, and an organic EL element. For example, a hydrogen generation photocatalyst can be obtained by combining the inorganic-organic composite material of the present invention with a platinum catalyst. Furthermore, by supporting metal or metal oxide fine particles as a co-catalyst on zeolite, various oxidation and reduction processes such as hydrogen generation and water decomposition can be made by utilizing the redox power of the charge-separated state of the electron donor / acceptor linked molecules. A photocatalytic reaction can also be performed. Furthermore, the photocatalyst of the present invention has a composite material formed by immobilizing an electron donor / acceptor linking molecule on zeolite, so that the photocatalyst is different from the case where the electron donor / acceptor linking molecule is used alone. Since it can be easily separated and recovered from the reaction solution after use, it can also be used as a recyclable photocatalyst. Moreover, the battery of this invention can also be used as a dye-sensitized solar cell by including the inorganic-organic composite material of this invention as a pigment | dye. Furthermore, the use of the inorganic-organic composite material of the present invention is not limited to these, and can be used for any use.

1 is a schematic diagram showing a production scheme of an inorganic-organic composite material of Example 1. FIG. FIG. 2 is a graph showing the amount of 9-mesityl-10-methylacridinium ions inserted into the AlMCM-41 type zeolite in Example 1. FIG. 3 is a spectrum diagram showing the XRD pattern of AlMCM-41 produced in Example 1. FIG. 4 is a spectrum diagram (document values) showing the XRD pattern of AlMCM-41. FIG. 5 shows the UV-visible absorption spectrum of a 9-mesityl-10-methylacridinium perchlorate (9-mesityl-10-methylacridinium ion, Acr ⁺ -Mes) acetonitrile solution and the inorganic organic of Example 1. It is a graph which shows collectively the diffuse reflection spectrum of a composite substance (Acr ⁺ -Mes @ AlMCM-41) suspension. FIG. 6 is an ESR spectrum diagram of the inorganic-organic composite material of Example 1 (Acr ⁺ -Mes @ AlMCM-41) after irradiation with high pressure mercury lamp (wavelength λ> 390 nm) at 25 ° C. (298 K) in a high vacuum. It is. FIG. 7 is an ESR spectrum diagram of the inorganic-organic composite material of Example 1 (Acr ⁺ -Mes @ AlMCM-41) after irradiation with high pressure mercury lamp (wavelength λ> 390 nm) at 100 ° C. (373 K) in a high vacuum. It is. FIG. 8 is a diagram showing the attenuation of the ESR signal of FIG. FIG. 9 is an ESR signal intensity diagram when the irradiation with the high-pressure mercury lamp (wavelength λ> 390 nm) light and the irradiation stop are repeated under the same conditions as in FIG. FIG. 10 shows the solid ultraviolet of the inorganic-organic composite material of Example 1 (Acr ⁺ -Mes @ AlMCM-41) before and after irradiation with high pressure mercury lamp (wavelength λ> 390 nm) at 25 ° C. (298 K) in high vacuum. It is a figure which shows a visible absorption spectrum (diffuse reflection spectrum). FIG. 11 shows together an attenuation curve of a diffuse reflection spectrum and an ESR signal attenuation curve when the inorganic-organic composite material (Acr ⁺ -Mes @ AlMCM-41) of Example 1 is irradiated with visible light at 100 ° C. (373 K). FIG.

Claims (13)

An inorganic-organic composite material formed from an inorganic material and an organic material,
The inorganic substance is aluminum-substituted mesoporous silica having a structure in which a part of silicon (Si) atoms of mesoporous silica is substituted with aluminum (Al) atoms,
The organic substance is an organic substance formed from an electron donor / acceptor linked molecule in which an electron donor site and an electron acceptor site are linked, or a salt thereof.
Inorganic organic composite material. In the organic substance,
The electron donor site is one or more electron donor groups;
The electron acceptor site is one or more aromatic cations;
The inorganic-organic composite material according to claim 1.   The aromatic ring forming the aromatic cation is a pyrrolium ring, pyridinium ring, quinolinium ring, isoquinolinium ring, acridinium ring, 3,4-benzoquinolinium ring, 5,6-benzoquinolinium ring, 6,7- Benzoquinolinium ring, 7,8-benzoquinolinium ring, 3,4-benzoisoquinolinium ring, 5,6-benzoisoquinolinium ring, 6,7-benzoisoquinolinium ring, 7 3. An inorganic substance according to claim 2, which is at least one selected from the group consisting of 1,8-benzoisoquinolinium rings and rings in which at least one of the carbon atoms constituting the rings is substituted with a heteroatom. Organic composite material. The electron donor / acceptor linking molecule is at least one selected from the group consisting of a compound represented by any one of the following formulas (1) to (8), a stereoisomer and a tautomer thereof. The inorganic-organic composite material according to claim 2 or 3.
In the above formulas (1) to (8),
R is a hydrogen atom or an arbitrary substituent,
Ar is the electron donating group and may be one or plural, and in the case of plural, they may be the same or different,
The aromatic ring that forms the aromatic cation may or may not have one or more arbitrary substituents other than R and Ar.   In the formulas (1) to (8), R is a hydrogen atom, an alkyl group, a benzyl group, a carboxyalkyl group (an alkyl group having a carboxyl group added to the terminal), an aminoalkyl group (an alkyl having an amino group added to the terminal) The inorganic-organic composite material according to claim 4, which is a group) or a polyether chain.   The electron donating group is a phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 2,3-dimethylphenyl group, 2,4-dimethylphenyl group, 2,5-dimethylphenyl group, 2, 6-dimethylphenyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, 2,3,4-trimethylphenyl group, 2,3,5-trimethylphenyl group, 2,3,6-trimethylphenyl The group according to any one of claims 2 to 5, which is at least one selected from the group consisting of a group, a mesityl group (2,4,6-trimethylphenyl group), and a 3,4,5-trimethylphenyl group. Inorganic organic composite material. The electron donor / acceptor linking molecule is at least one selected from the group consisting of a 9-substituted acridinium ion represented by the following formula (9), a tautomer and a stereoisomer thereof, The inorganic-organic composite material according to any one of claims 2 to 6.
In said Formula (9), R and Ar are the same as said Formula (1). The inorganic-organic composite material according to claim 1, wherein the electron donor-acceptor linking molecule is 9-mesityl-10-methylacridinium ion represented by the following formula (10).
  The aluminum-substituted mesoporous silica is an MCM-41 type, MCM-48 type, MCM-50 type, SBA-15 type, or FSM-16 type mesoporous silica in which some of the silicon (Si) atoms are aluminum (Al) atoms. The inorganic-organic composite material according to any one of claims 1 to 8, which is an aluminum-substituted mesoporous silica having a substituted structure.   The inorganic-organic composite material according to any one of claims 1 to 9, wherein the electron donor / acceptor linking molecule has a structure inserted into pores of the aluminum-substituted mesoporous silica.   A method for producing an inorganic-organic composite material according to claim 1, comprising a dipping step in which the aluminum-substituted mesoporous silica is dipped in a solution of the electron donor / acceptor linked molecule or a salt thereof.   The manufacturing method according to claim 11, further comprising a pretreatment step of firing the aluminum-substituted mesoporous silica prior to the dipping step.   11. The inorganic organic composite material according to claim 1, which is used as a photocatalyst, a photosensitizer, a dye, an oxidant, a reducing agent, a battery, a dye-sensitized solar cell, or an organic EL element. Product.