JP4887694B2 - PHOTOELECTRIC CONVERSION ELEMENT AND ITS MANUFACTURING METHOD, PHOTOELECTRIC CONVERSION ELEMENT MODULE, ELECTRONIC DEVICE, MOBILE BODY, POWER GENERATION SYSTEM, DISPLAY AND MANUFACTURING METHOD - Google Patents

Description

  The present invention relates to a photoelectric conversion element, a method for manufacturing the same, a photoelectric conversion element module, an electronic device, a moving body, a power generation system, a display, and a method for manufacturing the same, for example, a dye-sensitized type using a semiconductor electrode composed of a semiconductor fine particle assembly. It is suitable for application to solar cells.

In recent years, dye-sensitized solar cells have attracted attention as a next-generation solar cell that replaces silicon (Si) -based solar cells and the like, and have been widely studied (for example, see Non-Patent Document 1).
In general, the necessary characteristics of solar cells include stable photoelectric conversion characteristics over a long period of time, but dye-sensitized solar cells generally contain a liquid electrolyte component as a component. In order to obtain stable photoelectric conversion characteristics over a long period of time, avoid degradation of performance due to volatilization or leakage of electrolyte components from the battery, or infiltration of moisture, oxygen, or other components from the atmosphere into the electrolyte. is important.

  As a method for solving this problem, a method using a non-volatile molten salt electrolyte as an electrolyte (for example, see Patent Document 1) and a method using a gel electrolyte (for example, see Patent Document 2) are proposed. However, other methods for sealing the electrolyte using a liquid or film adhesive have been proposed. As a method of sealing the electrolyte using this adhesive, a method of applying an epoxy resin or silicone rubber (see, for example, Patent Document 3), a sealing material mainly composed of glass or ceramics, and 450 ° C. A method of heat treatment at a moderate temperature (for example, see Patent Document 4), a method of applying a sealing material made of silicone resin, polyolefin, butyl rubber, or the like (for example, see Patent Document 5) are known.

By arranging a plurality of solar cells in the space between the transparent base material and the protective member, filling this space with a two-component mixed curable resin, and embedding the solar cells in this resin A method for producing a solar cell module has been proposed (see, for example, Patent Document 6).
In addition, an optical disk is manufactured by bonding a plastic transparent substrate on which an optical recording film is formed and another plastic transparent substrate with a two-liquid non-mixing adhesive such as a two-liquid non-mixing acrylic adhesive. It is sometimes known that the thickness of the adhesive layer is 20 μm or 60 μm (see, for example, Patent Document 7). Two-liquid non-mixing type adhesive is used for sealing an electrolyte of a dye-sensitized solar cell or liquid crystal. It is neither disclosed nor suggested to be used for sealing a liquid crystal of a display.

Nature 353,737, (1991) JP 2001-196105 A International Publication No. 01/34564 Pamphlet JP 2000-200267 A JP 2000-348783 A JP 2004-119306 A JP 2003-86822 A Japanese Examined Patent Publication No. 4-43332

  In the above-described conventional method of sealing an electrolyte with an adhesive in a dye-sensitized solar cell, the dye-sensitized solar cell is not suitable for the reason that treatment by heating, pressurization, or ultraviolet irradiation is necessary at the time of bonding. In addition to the possibility of adversely affecting the characteristics, there are problems such as durability against long-term use and low adaptability to the manufacturing process, which is not sufficient.

  That is, when a film-like material represented by a heat-sealing film is used as an adhesive, a thin-film substrate having a thickness of 100 μm or less generally used for a photoelectric conversion element such as a dye-sensitized solar cell is predetermined. It is difficult to securely attach to the position of this, which is not suitable in terms of productivity. On the other hand, even when a coating type adhesive is used, after the substrate on which the semiconductor electrode is formed and the substrate on which the counter electrode is formed are bonded with an adhesive, heating, pressurization, or ultraviolet irradiation is performed to cure the adhesive. Therefore, there is a concern that this process becomes a cause of deterioration of element constituents, particularly organic substances used in the elements.

Accordingly, the problem to be solved by the present invention is that a photoelectric conversion element such as a dye-sensitized solar cell that can obtain stable photoelectric conversion characteristics over a long period of time and has excellent process compatibility, a method for producing the same, and such a method It is providing the photoelectric conversion element module comprised by a photoelectric conversion element.
Another problem to be solved by the present invention is to provide an electronic device, a moving body, and a power generation system using the photoelectric conversion element as described above.
Still another problem to be solved by the present invention is to provide a display capable of obtaining stable characteristics over a long period of time and having excellent process compatibility, and a method for manufacturing the same.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that in order to achieve both good adhesion and sealing properties of a substrate and process suitability in a dye-sensitized solar cell, etc. It has been found that it is most effective to use a mixed two-component adhesive, and the present invention has been devised. The outline will be described as follows.

  Generally used two-component mixed adhesives are used by first mixing the two components and then applying to the adherend, but because pot life and curing time are in a trade-off relationship, For example, when trying to take a long pot life, the curing time becomes long, which is not desirable from the viewpoint of productivity. On the other hand, when trying to shorten the curing time, since the pot life is shortened, in the production process, for example, when the production line is stopped for some reason, the mixed adhesive may be unusable. . Further, as an inherent problem of the two-component mixed adhesive, when the two components are not sufficiently mixed, a partially uncured portion may be generated. In particular, when it is necessary to maintain a volatile organic solvent in the electrolyte layer for a long period of time as in a dye-sensitized solar cell, the presence of pinholes in the sealing portion causes deterioration in device characteristics. .

  On the other hand, in the case of a non-mixing type two-component adhesive, since it is premised on mixing and curing at the molecular level by self-diffusion of two components, there is a possibility of causing problems such as the above-mentioned poor mixing. In addition, there is no trade-off problem between pot life and curing time. Further, in the case of a non-mixing type two-component adhesive, it is known that the curing time is longer than that of a mixed adhesive, but it is required for an electrochemical device such as a dye-sensitized solar cell. Since the thickness of the adhesive layer is generally as thin as several tens to 100 μm, the time required for adhesion is usually short, and if necessary, the curing speed can be increased by heating or depressurizing at a temperature that does not adversely affect the properties. This is also not a problem.

The present invention has been devised based on the above examination by the present inventors.
That is, in order to solve the above problem, the first invention
In the photoelectric conversion element having the first substrate and the second substrate facing each other,
The first substrate and the second substrate are bonded to each other by a non-mixed two-component adhesive.

The second invention is
In a method for manufacturing a photoelectric conversion element having a first substrate and a second substrate facing each other,
The first component and the second component of the non-mixed two-component adhesive are applied to predetermined portions of the first substrate and the second substrate, respectively, and the first component applied to the first substrate is applied. The first substrate and the second substrate are bonded together so that the first component and the second component applied to the second substrate are in contact with each other. The second substrate is bonded to the second substrate.

In the first and second inventions, the thickness of the adhesive layer by the unmixed two-component adhesive is determined as necessary, but is generally 500 μm or less, typically 200 μm or less, more typically Specifically, it is several tens to 100 μm. As the non-mixing type two-component adhesive, it is particularly desirable to use an adhesive whose curing proceeds by an addition reaction. For example, when a non-mixed two-component adhesive is cured by condensation, H ₂ O generated by the reaction may remain inside the device, which may cause a deterioration in characteristics. However, if there is no problem in practical use, a reaction other than the addition reaction, for example, a non-mixed two-component adhesive that cures by condensation may be used.

  When adhering the first substrate and the second substrate, the first component and the second component of the non-mixed two-component adhesive are respectively applied to predetermined portions of the first substrate and the second substrate. The first substrate and the second substrate are applied so that the first component applied to the first substrate and the second component applied to the second substrate are in contact with each other. The first substrate and the second substrate are bonded together by bonding and curing the adhesive. When the adhesive component contains a solvent component, a thin film composed of the adhesive component is formed on the first substrate and the second substrate by removing the solvent component by a method such as heating and decompression after application.

  In this non-mixing type two-component adhesive, it is desirable that a component causing a curing reaction is contained in an amount larger than that required when the reaction theoretically proceeds. The amount contained in excess is determined by the composition of the adhesive, but specifically, for example, it is desirable that the amount is 0.1 to 100%, more preferably 5 to 20%. When the component causing the curing reaction contains only the same amount as that required when the reaction proceeds theoretically, the two components of the non-mixed two-component adhesive are applied. When the thicknesses of the first and second substrates do not completely match, there is a possibility that the adhesion is insufficient at the interface between the first substrate and the second substrate. On the other hand, if it is present in an excessive amount, the cured material itself may adversely affect the device as a residual impurity. Further, the hardening component may contain a noble metal and the like, and in that case, it is not realistic to include excessively more than necessary from the viewpoint of cost.

This non-mixed two-component adhesive includes epoxy, butyl rubber, silicone rubber, etc., but has long-term stability and chemical stability with respect to constituent elements of photoelectric conversion elements such as organic solvents and iodine. Anything can be used.
In this photoelectric conversion element, typically, the first substrate has a first electrode on a surface facing the second substrate, and the second substrate has a second surface on the surface facing the first substrate. Electrode. Typically, the first electrode is a semiconductor electrode made of a semiconductor fine particle assembly, and the second electrode is a counter electrode. In this case, the semiconductor electrode and the counter electrode are provided facing each other at a predetermined interval, and the electrolyte layer is provided between them in a state of being sealed with an adhesive layer made of a non-mixed two-component adhesive. It is done.

  The above-mentioned semiconductor fine particle joined body is a semiconductor fine particle sintered body, a semiconductor fine particle aggregate produced by irradiation of electromagnetic waves such as microwaves, a semiconductor fine particle aggregate by electrostatic interaction, or a binder polymer or a brazing material. However, the present invention is not limited to these.

Further, the semiconductor fine particles constituting the semiconductor fine particle joined body refer to those composed of a semiconductor having an average primary particle size (average particle size of primary particles) of 1 mm or less and causing interband transition. The shape of the semiconductor fine particles is not particularly limited, and may be any shape such as a rod shape, a needle shape, a cone shape, or a fiber shape in addition to a spherical shape. Further, any kind of semiconductor may be used as long as interband transition occurs, but representative ones are TiSrO ₃ , BaTiO ₃ , TiO ₂ , Nb ₂ O ₅ , MgO, ZnO. , WO ₃ , Bi ₂ O ₃ , CdS, CdSe, CdTe, In ₂ O ₃ , SnO _2, and various metal oxide semiconductors or compound semiconductors. Of these, TiO ₂ (particularly anatase type structure) is particularly preferred. However, the types of semiconductors are not limited to these, and two or more of these may be mixed or combined.

The average primary particle size of the semiconductor fine particles constituting the semiconductor fine particle joined body is preferably 1 to 200 nm, particularly preferably 5 to 100 nm, and further preferably 5 to 30 nm. Further, semiconductor fine particles having an average primary particle size larger than the average primary particle size are mixed with the semiconductor fine particles having an average primary particle size, and incident light is scattered by the semiconductor fine particles having a large average primary particle size. It is also possible to improve the rate. In this case, the average primary particle size of the semiconductor fine particles to be mixed separately is preferably 20 to 1000 nm, more preferably 20 to 500 nm, and still more preferably 100 to 500 nm. In these semiconductor fine particles, the particle size distribution may have a single peak or may have two or more peaks or a broad particle size distribution. Moreover, these semiconductor fine particles may be made of the same material or different materials. The semiconductor fine particles to be mixed separately can be made of a high refractive index material such as rutile TiO ₂ , for example.

  As the sensitizing dye supported on the semiconductor fine particles, any sensitizing dye can be used as long as it provides a sensitizing action. Specifically, for example, bipyridine, phenanthrin derivative, rhodamine B, rose bengal, eosin Xanthene dyes such as erythrosine, cyanine dyes such as quinocyanine and cryptocyanine, basic dyes such as phenosafranine, cabrio blue, thiocin and methylene blue, porphyrin compounds such as chlorophyll, zinc porphyrin and magnesium porphyrin, azo dyes and phthalocyanines Examples thereof include compounds, coumarin compounds, anthraquinone dyes, and polycyclic quinone dyes. As the sensitizing dye, a dye that forms a complex with a metal such as ruthenium (Ru), zinc (Zn), platinum (Pt), or palladium (Pd) may be used. Among these, Ru bipyridine complex compounds are particularly preferable because of their high quantum yield. Two or more of these sensitizing dyes can be used simultaneously.

  The method for supporting the sensitizing dye on the semiconductor fine particle assembly is not particularly limited. For example, the sensitizing dye may be alcohols, nitriles, nitromethane, halogenated hydrocarbons, ethers, dimethyl sulfoxide, amides, N -Dissolve in a solvent such as methylpyrrolidone, 1,3-dimethylimidazolidinone, 3-methyloxazolidinone, esters, carbonates, ketones, hydrocarbons, water, etc. A method of applying a dye solution to a semiconductor fine particle assembly is common. It is also possible to use a method in which the sensitizing dye is dissolved in a paste in which semiconductor fine particles are dispersed, and the semiconductor fine particles on which the sensitizing dye is supported are applied and press-molded. In this case, the adsorption amount of the sensitizing dye molecule to one semiconductor fine particle is 1 to 100,000 molecules, and more preferably 1 to 10,000 molecules. Carboxylic acids such as deoxycholic acid may be added for the purpose of reducing association between sensitizing dyes. Moreover, an ultraviolet absorber can also be used together.

  The semiconductor electrode is typically provided on a transparent conductive substrate as the first substrate. The transparent conductive substrate may be a transparent conductive substrate formed on a conductive or non-conductive transparent support substrate, or may be a conductive transparent substrate as a whole. The material in particular of this transparent support substrate is not restrict | limited, A various base material can be used if it is transparent. This transparent support substrate is preferably one that is excellent in moisture and gas barrier properties, solvent resistance, weather resistance, and the like entering from the outside of the photoelectric conversion element. Specifically, a transparent inorganic substrate such as quartz or glass, polyethylene Terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, polyethylene, polypropylene, polyphenylene sulfide, polyvinylidene fluoride, tetraacetylcellulose, brominated phenoxy, aramids, polyimides, polystyrenes, polyarylates, polysulfones, polyolefins, etc. Although a transparent plastic substrate is mentioned, it is not limited to these. As this transparent support substrate, it is preferable to use a transparent plastic substrate in consideration of processability, lightness and the like. Further, the thickness of the transparent support substrate is not particularly limited, and can be freely selected depending on the light transmittance, the shielding property between the inside and outside of the photoelectric conversion element, and the like.

The lower the surface resistance of the transparent conductive substrate, the better. Specifically, the surface resistance of the transparent conductive substrate is preferably 500Ω / □ or less, and more preferably 100Ω / □ or less. When a transparent conductive film is formed on a transparent support substrate, known materials can be used. Specifically, indium-tin composite oxide (ITO), fluorine-doped SnO ₂ (FTO), SnO _{2 and the} like, but are not limited to these, and two or more of these may be used in combination. In addition, for the purpose of reducing the surface resistance of the transparent conductive substrate and improving the current collection efficiency, it is also possible to pattern a highly conductive metal wiring on the transparent conductive substrate.

  By the way, in a dye-sensitized photoelectric conversion element such as a dye-sensitized solar cell, an additive composed of a substance that binds to a dye-sensitized semiconductor fine particle assembly is usually added to prevent reverse electron transfer in an electrolyte solution. . As this additive, tert-butylpyridine, 1-methoxybenzimidazole, phosphonic acid having a long-chain alkyl group (about C = 13) or the like is used. The characteristics of these additives are that they can be uniformly mixed in the electrolytic solution and have a functional group capable of binding to the dye-sensitized semiconductor fine particle assembly. However, according to the knowledge of the present inventors, in the conventional dye-sensitized solar cell, the dye previously adsorbed on the surface of the semiconductor fine particle assembly after the electrolyte solution is encapsulated is eluted, and the photoelectric conversion efficiency is increased. It was confirmed that it deteriorated rapidly. Therefore, it is necessary to prevent the elution of the dye previously adsorbed on the semiconductor fine particle joined body while preventing the reverse electron transfer reaction and to improve the photoelectric conversion efficiency. For this purpose, instead of adding an additive to the electrolytic solution, the semiconductor fine particle assembly is preliminarily adsorbed with a dye and an additive, and at this time, the additive is adsorbed in a gap between the dyes, It is effective not to contain any additives. As a method for this, for example, after the semiconductor fine particle assembly to which the dye is adsorbed is immersed in a solution containing the additive, the additive is adsorbed on the surface of the semiconductor fine particle assembly in the gap portion between the dyes. An electrolyte containing no additive is sealed between the semiconductor fine particle assembly on which the dye and the additive are adsorbed and the counter electrode. By doing this, the additive adsorbed on the dye-sensitized semiconductor fine particle assembly can prevent the reverse electron transfer reaction and prevent the elution of the dye by the electrolyte, effectively reducing the deterioration of photoelectric conversion efficiency over time. Can be prevented. As an additive, it has a functional group (imidazolyl group, carboxy group, phosphone group, etc.) that binds to the semiconductor fine particle assembly, does not desorb as a result of bonding, and as a result of adsorption, the surface of the semiconductor fine particle assembly is exposed. Specifically, for example, phosphonic acid having a long-chain alkyl group (about C = 13) such as tert-butylpyridine, 1-methoxybenzimidazole, and decanephosphoric acid is used. .

  Any material can be used as the counter electrode as long as it is a conductive material, but an insulating material can also be used if a conductive layer is provided on the side facing the semiconductor electrode. However, it is preferable to use an electrochemically stable substance as the counter electrode, and specifically, platinum, platinum black, carbon, a conductive polymer, or the like is preferably used. The counter electrode may be formed by forming a film of the above substance on a transparent or opaque substrate such as a quartz glass substrate as the second substrate, or may be a platinum substrate.

The form of the carbon-based material used for the counter electrode is not particularly limited and may be various. Specifically, for example, acicular carbon, ketjen black, acetylene black, fullerene, carbon nanotube (including carbon nanohorn), etc. is there. These various forms of carbon may exhibit even better effects by polymerization, introduction of functional groups, or doping of N atoms. The specific surface area of the carbon is desirably large in order to improve the charge transfer rate on the counter electrode, and is generally selected to be at least 10 m ² / g or more, preferably 100 m ² / g or more. It is known that the surface area of the counter electrode produced using this carbon is 100 times or more the projected area. The particle size of the carbon is generally 100 nm or less, but carbon having a larger particle size can be mixed for the purpose of improving the formability of the counter electrode. The particle diameter of carbon having a larger particle diameter is not particularly limited, but for example, when the thickness of the counter electrode is 20 to 30 μm at the maximum, it is about 1 to several μm at the maximum.

  The carbon-based material preferably carries a metal in order to realize rapid charge transfer on the counter electrode. The metal is, for example, at least one selected from the group consisting of platinum (Pt), ruthenium (Ru), cobalt (Co), titanium (Ti), nickel (Ni), aluminum (Al), and gold (Au). These metals are also included, and mixtures or compounds thereof are also included. By loading a metal on carbon, better electrode characteristics can be obtained than with carbon alone, and by increasing the amount of metal loaded, the electrode characteristics are improved, but the effect of improving the characteristics compared to carbon alone In order to clearly obtain the above, it is desirable that the amount of the metal supported on the carbon is at least 5 wt% (wt%) or more with respect to the carbon. On the other hand, in the case of using noble metal Pt as the metal to be supported, from the viewpoint of emphasizing cost reduction, it is desirable to suppress the amount of use as much as possible.

  The carbon-based material is typically combined with a binder. As this binder, known materials, for example, various pitches, rubbers, synthetic resins and the like can be used. This binder is preferably insoluble in the electrolytic solution. Specifically, this binder is, for example, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. Fluororesins such as coalescence (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), polychlorotrifluoroethylene (PCTFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), polyvinyl fluoride (PVF), Vinylidene fluoride-hexafluoropropylene fluorine rubber (VDF-HFP fluorine rubber), vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene fluorine rubber (VDF-HFP-TFE fluorine) Raw rubber), vinylidene fluoride-pentafluoropropylene-based fluororubber (VDF-PFP-based fluororubber), vinylidene fluoride-pentafluoropropylene-tetrafluoroethylene-based fluororubber (VDF-PFP-TFE-based fluororubber), vinylidene fluoride Ride-perfluoromethyl vinyl ether-tetrafluoroethylene fluoro rubber (VDF-PFMVE-TFE fluoro rubber), vinylidene fluoride-chlorotrifluoroethylene fluoro rubber (VDF-CTFE fluoro rubber), etc. Fluoro rubber, Tetrafluoroethylene-propylene fluoro rubber (TFE-P fluoro rubber), Tetrafluoroethylene-perfluoroalkyl vinyl ether fluoro rubber, Thermoplastic fluoro rubber For example, Daikin Industries Ltd. DAI-EL Thermoplastic), polyethylene glycol (PEG), ethylene propylene diene monomer (EPDM), may be used cellulose such as carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC). Among these, polyvinylidene fluoride (PVDF) is preferable in that it can be dissolved particularly by a solvent, can be easily mixed with a slurry, and has excellent stability against photothermal heat. As the binder, two or more of the above may be mixed and used.

The binder is usually used in a state where a powdered binder material is dissolved or dispersed using a solvent, but may be used as a powder without using a solvent. The solvent to be used is not particularly limited, and various solvents such as water, methyl ethyl ketone, cyclohexanone, isophorone, N-methylpyrrolidone (NMP), N, N-dimethylformamide, N, N-dimethylacetamide and toluene are selected according to the purpose. do it.
The amount of the binder added is not particularly limited as long as necessary adhesion to the substrate required in the subsequent production process or use can be obtained, but generally 5 wt% or more with respect to carbon, particularly preferably. It is 15 wt% or more. If the amount of the binder is too small, the adhesion to the substrate is insufficient, and if the amount of the binder is too large, the characteristics of the electrode are insufficient.

  When a carbon-based material is used for the counter electrode, the method of forming the counter electrode is not particularly limited, but can be easily formed by the following method. That is, for example, NMP and PVDF are added to carbon carrying a metal such as Pt, and these are mixed until they are uniform, and are made of glass, polymer film, metal, etc. by screen printing or blade coating. A counter electrode made of metal-supported carbon can be formed by coating on a substrate, drying it using heat, reduced pressure, or both, and pressing as necessary. Here, a transparent conductor layer such as ITO or FTO, a metal layer such as Pt, Ru, or Ni, or a carbon layer may be formed on the glass, polymer film, or metal, and these are laminated. It doesn't matter. Moreover, you may use a heating together when pressing. The temperature at this time is preferably equal to or higher than the glass transition point of PVDF to be used.

Moreover, as a binder, water-soluble polymers, such as a cellulose and PTFE, can also be used. In this case, while gradually adding water and isopropanol, 50 wt% binder polymer is mixed with carbon until it becomes uniform, and is made of glass, polymer film, metal, etc. by screen printing, blade coating, etc. The counter electrode can be formed by coating on a conductive substrate, drying it using heat, reduced pressure, or both, and pressing it. In this case, it is desirable that the temperature when heating is used is not less than the glass transition point of the binder used.
As a substrate for forming a counter electrode using a carbon-based material, a substrate similar to that for forming a counter electrode using a conductive polymer can be used.

  As the conductive polymer used for the counter electrode, generally known ones can be used. Specifically, for example, polyacetylene, polypyrrole, polyaniline, polythiophene, polyphenylene, polyacene, polyazulene, polyindole or These derivatives can be used, but are not limited thereto. Particularly suitable conductive polymers include polyethylene dioxythiophene (PEDOT) and polyalkylthiophenes.

When a conductive polymer is used for the counter electrode, the method for forming the counter electrode is not particularly limited. For example, it is easily formed by a commonly used method such as a thermal polymerization method or an electrochemical polymerization method (electrolytic polymerization method). be able to. Specifically, for example, an ITO substrate is spin-coated with ethylenedioxythiophene (EDOT), Fe (III) p-toluenesulfate, n-BuOH solution of imidazole, thermally polymerized at 100 ° C. for 5 minutes, and then with MeOH. By washing, a PEDOT counter electrode can be obtained. Alternatively, EDOT 0.2M, LiClO ₄ 0.2M propylene carbonate (PC) solution as the electrolytic solution, Pt as the counter electrode, Ag / Ag ^{+ as} the reference electrode, ITO as the working electrode, and 100 μA / cm ² by constant current electrolysis. A PEDOT counter electrode can be formed on ITO by electrolytic polymerization.

For the above electropolymerization, not only a constant current method but also a generally known method such as a constant potential method, a potential sweep method, and a pulse current method can be used. In addition, a technique of polymerizing in a liquid crystal to have a specific morphology can be used as appropriate. It is also possible to use a polymerization method in a magnetic field. In this case, the strength of the magnetic field is not particularly limited as long as the desired purpose can be realized. As a polymerization solvent for the conductive polymer, in addition to an organic solvent such as water, CH ₃ CN, and propylene carbonate, a polymer solid electrolyte, a precursor thereof, a room temperature molten salt, or the like can be used alone or in combination. .
The counter electrode may be formed by a method of casting or spin coating a solution in which a conductive polymer is dissolved. Examples of the polymer solution include PEDOT / PSS (polystyrene sulfonic acid) aqueous dispersion. In this case, a binder polymer may be used as necessary.

A conductive substrate is typically used as a substrate for forming a counter electrode using a conductive polymer. The conductive substrate may be a single conductive substrate as a whole, or a conductive substrate formed on a conductive or non-conductive support substrate. The material of the substrate is not particularly limited as long as it is a transparent conductive material such as ITO, fluorine-doped SnO ₂ (FTO), SnO _2, or a highly conductive material such as metal or carbon. It is desirable to be chemically and electrochemically stable. Furthermore, a method of combining with a porous carbon electrode, a metal-supported carbon electrode, platinum black, metal fine particles, etched ITO, or the like can also be used.

The electrolyte layer is obtained by dissolving at least one substance system (redox system) that reversibly changes the state of oxidation / reduction in the electrolyte. Examples of the oxidation-reduction system include, for example, halogens such as I− / I ₃ − and Br− / Br ₂ , pseudohalogens such as quinone / hydroquinone and SCN − / (SCN) ₂ , iron (II) ions / iron ( III) ions, copper (I) ions / copper (II) ions, and the like, but are not limited thereto.
The electrolyte may be a liquid electrolyte, or may be a gel electrolyte, a polymer solid electrolyte, an inorganic solid electrolyte, or the like containing this in a polymer material. Specific examples of the electrolyte include a combination of iodine (I ₂ ) and metal iodide or organic iodide, a combination of bromine (Br ₂ ) and metal bromide or organic bromide, and ferrocyanate / ferricyan. Metal complexes such as acid salts and ferrocene / ferricinium ions, sodium sulfide, sulfur compounds such as alkylthiol / alkyl disulfide, viologen dyes, hydroquinone / quinone, and the like can be used. Preferred examples of the cation of the metal compound include Li, Na, K, Mg, Ca, and Cs, and preferred examples of the cation of the organic compound include tetraalkylammoniums, pyridiniums, imidazoliums, and the like. These may be used in combination of two or more. Among these, an electrolyte in which I ₂ and an imidazolium compound such as LiI, NaI, or imidazolium iodide are combined is preferable. The concentration of the electrolyte salt is preferably 0.05M to 5M, and more preferably 0.2M to 2M with respect to the solvent. The concentration of I ₂ or Br ₂ is preferably 0.0005M to 1M, more preferably 0.001 to 0.2M. Various additives such as 4-tert-butylpyridine and carboxylic acid can be added for the purpose of improving the open circuit voltage.

Solvents for the electrolyte layer include, for example, nitriles such as acetonitrile, carbonates such as propylene carbonate and ethylene carbonate, gamma butyrolactone, pyridine, dimethylacetamide, other polar solvents, and methylpropylimidazolium-iodine (MPII) Salts or mixtures thereof can be used. More generally, the electrolyte layer solvent includes water, alcohols, ethers, esters, carbonate esters, lactones, carboxylic acid esters, phosphate triesters, heterocyclic compounds, nitriles, Ketones, amides, nitromethane, halogenated hydrocarbons, dimethyl sulfoxide, sulfolane, N-methylpyrrolidone, 1,3-dimethylimidazolidinone, 3-methyloxazolidinone, hydrocarbons, etc. can be used. A mixture of these can also be used. In addition, tetraalkyl, trialkylsulfonium, pyridinium, and imidazolium ionic liquids can be used as the solvent.
Further, a supporting electrolyte may be added to the electrolyte as necessary. Examples of the supporting electrolyte include inorganic salts such as lithium iodide and sodium iodide, and molten salts such as imidazolium and quaternary ammonium.

By the way, in a dye-sensitized photoelectric conversion element such as a dye-sensitized solar cell, a dye-sensitized semiconductor fine particle assembly made of an n-type semiconductor is usually soaked with an electrolyte that is a liquid hole transfer layer. Because of the structure, there is a site where the electrolyte is in direct contact with the transparent conductive layer, and leakage current due to a reverse electron transfer reaction from the transparent conductive layer to the electrolyte becomes a problem. Since this leakage current lowers the fill factor and open circuit voltage of the dye-sensitized photoelectric conversion element, it becomes a big problem in improving the photoelectric conversion efficiency. Therefore, it is important to significantly reduce the leakage current due to the reverse electron transfer reaction from the transparent conductive layer to the electrolyte. For this purpose, it is effective to provide a structure in which a transparent conductive layer and a transparent protective layer made of a metal oxide are sequentially provided on the first substrate, and a dye-sensitized semiconductor fine particle assembly is provided on the protective layer. is there. By doing so, the transparent conductive layer is covered with a protective layer made of a metal oxide and is cut off from the electrolyte, and since the transparent conductive layer is not in direct contact with the electrolyte, the leakage current can be greatly reduced. It becomes. The dye-sensitized photoelectric conversion element having such a structure has a high fill factor and an open circuit voltage, and can realize a dye-sensitized photoelectric conversion element excellent in photoelectric conversion efficiency. The metal oxide constituting this protective layer is specifically selected from the group consisting of Nb ₂ O ₅ , Ta ₂ O ₅ , TiO ₂ , Al ₂ O ₃ , ZrO ₂ , TiSrO ₃ and SiO _2, for example. At least one metal oxide. The thickness of the protective layer is not particularly limited, but if it is too thin, the barrier between the transparent conductive layer and the electrolyte is poor, and conversely, if it is too thick, the transmittance is reduced and electron injection into the transparent conductive layer is lost. As a result, there will be a preferred thickness. This thickness is usually from 0.1 to 500 nm, particularly preferably from 1 to 100 nm.

  The manufacturing method of the photoelectric conversion element is not particularly limited, for example, the electrolyte composition is liquid, or can be gelled inside the photoelectric conversion element, and in the case of a liquid electrolyte composition before introduction, The semiconductor electrode and the counter electrode are opposed to each other, and the substrate portion on which the semiconductor electrode is not formed is sealed with the non-mixed two-component adhesive so that the two electrodes do not contact each other. At this time, although there is no restriction | limiting in particular in the magnitude | size of the clearance gap between a semiconductor electrode and a counter electrode, Usually, it is 1-100 micrometers, More preferably, it is 1-50 micrometers. If the distance between the electrodes is too long, the photocurrent decreases due to an increase in internal resistance. Moreover, although the inlet which injects the solution of electrolyte composition is required, the place of an inlet is not specifically limited. Although there is no restriction | limiting in particular in the pouring method, The method of pouring in the inside of the said cell sealed beforehand and opened the injection port of the solution is preferable. In this case, a method of dropping a few drops of the solution at the injection port and injecting the solution by capillary action is simple. In addition, the injection operation can be performed under reduced pressure or under heating as necessary. After the solution is completely injected, the solution remaining at the inlet is removed and the inlet is sealed. Although there is no restriction | limiting in particular also in this sealing method, If necessary, it can also seal by affixing a glass plate or a plastic substrate with a sealing agent. In the case of a gel electrolyte using a polymer or the like, or an all solid electrolyte, a polymer solution containing an electrolyte composition and a plasticizer is volatilized and removed by a casting method on a semiconductor electrode carrying a dye. After completely removing the plasticizer, sealing is performed in the same manner as in the above method. This sealing is preferably performed using a vacuum sealer or the like under an inert gas atmosphere or under reduced pressure. After sealing, in order to sufficiently impregnate the electrolyte into the semiconductor fine particle layer, it is possible to perform heating and pressurizing operations as necessary.

The photoelectric conversion element can be manufactured in various shapes depending on the application, and the shape is not particularly limited.
The photoelectric conversion element is typically a dye-sensitized photoelectric conversion element, for example, a dye-sensitized solar cell. However, the photoelectric conversion element may be other than a dye-sensitized solar cell, such as a dye-sensitized photosensor. This photoelectric conversion element can be used for anything that requires electric power and can be of any size. For example, it can be used for electronic equipment, moving objects, power units, construction machines, machine tools, power generation systems, etc. The output, size, shape, etc. are determined depending on the application.

The third invention is
In the photoelectric conversion element module in which a plurality of photoelectric conversion elements are arranged and wired,
At least one of the photoelectric conversion elements is
A first substrate and a second substrate facing each other;
It is a photoelectric conversion element in which the first substrate and the second substrate are bonded to each other with a non-mixed two-component adhesive.

In this case, all of the plurality of photoelectric conversion elements may be photoelectric conversion elements having the above-described configuration, or one or more photoelectric conversion elements having the above-described configuration and photoelectric conversion elements having another configuration. A combination of these may be used. In addition, the plurality of photoelectric conversion elements include one or more dye-sensitized photoelectric conversion elements having the above-described configuration and photoelectric conversion elements other than the dye-sensitized photoelectric conversion elements, for example, conventional general silicon It may be a combination with a system photoelectric conversion element or the like.
The form of this photoelectric conversion element module is not particularly limited, and can be determined as necessary. In addition, the arrangement method of the plurality of photoelectric conversion elements is not particularly limited and can be determined as necessary. Specifically, for example, two-dimensionally arranging them in parallel or stacking a plurality of stages to form a tertiary It can be arranged originally. In order to form a photoelectric conversion element module, specifically, for example, a plurality of these photoelectric conversion elements are arranged and sandwiched between two transparent substrates (such as a glass substrate), and these photoelectric conversions are performed. After wiring between the elements, silicone resin or the like is filled in the gaps between the elements and cured. The wiring method between the plurality of photoelectric conversion elements may be either serial or parallel.
In the third invention, the matters other than those described above are explained in relation to the first and second inventions unless they are contrary to their properties.

The fourth invention is:
In an electronic apparatus having a photoelectric conversion element having a first substrate and a second substrate facing each other,
The first substrate and the second substrate are bonded to each other by a non-mixed two-component adhesive.
This electronic device may basically be any type, and includes both portable and stationary types. Specific examples include cell phones, mobile devices, robots, personal computers, and the like. Computers, game devices, in-vehicle devices, home appliances, industrial products, etc.
In the fourth invention, the matters other than those described above are explained in relation to the first and second inventions unless they are contrary to the nature.

The fifth invention is:
In a moving body having a photoelectric conversion element having a first substrate and a second substrate facing each other,
The first substrate and the second substrate are bonded to each other by a non-mixed two-component adhesive.
This moving body may be basically any type, and specific examples include automobiles, two-wheeled vehicles, aircraft, rockets, and space ships.
In the fifth invention, what has been described in relation to the first and second inventions holds true for matters other than those described above, unless they are contrary to the nature thereof.

The sixth invention is:
In a power generation system having a photoelectric conversion element having a first substrate and a second substrate facing each other,
The first substrate and the second substrate are bonded to each other by a non-mixed two-component adhesive.
This power generation system may be basically any type, and its scale is not limited.
In the sixth invention, the matters other than those described above are explained in relation to the first and second inventions unless they are contrary to the nature.

The seventh invention
In a display having a first substrate and a second substrate facing each other,
The first substrate and the second substrate are bonded to each other by a non-mixed two-component adhesive.

The eighth invention
In a method for manufacturing a display having a first substrate and a second substrate facing each other,
The first component and the second component of the non-mixed two-component adhesive are applied to predetermined portions of the first substrate and the second substrate, respectively, and the first component applied to the first substrate is applied. The first substrate and the second substrate are bonded together so that the first component and the second component applied to the second substrate are in contact with each other. The second substrate is bonded to the second substrate.

  In the seventh and eighth inventions, the display has a first substrate and a second substrate facing each other, and as long as these are bonded and sealed at a predetermined portion, any display However, specific examples include a liquid crystal display, an organic electroluminescence (EL) display, electronic paper, a field emission display (FED), and the like. In these displays, the thickness of the adhesive layer is generally several μm to 500 μm. In particular, for electronic paper, for example, about several tens to 100 μm, for liquid crystal displays and field emission displays, for example, 200 to 300 μm, and for organic EL displays, several μm. It is. In a liquid crystal display, for example, a TFT (thin film transistor) or a pixel electrode as a pixel switching element is formed on one substrate, a counter electrode is formed on the other substrate, and liquid crystal is sealed between these substrates. The In an organic EL display, for example, element layers such as an anode, a hole transport layer, a light-emitting layer, an electron transport layer, and a cathode are formed on one substrate, and these element layers are sealed between the other substrate. The In the electronic paper, for example, in a microcapsule electrophoresis system, a microcapsule is coated on one substrate, a transparent electrode is formed on the other substrate, and an organic EL element is used, an element on one substrate A layer is formed, and these element layers are sealed between the other substrate. In a field emission display, a cathode, an emitter, a gate electrode, and the like are formed on one substrate, an anode, a phosphor, and the like are formed on the other substrate, and a vacuum state is maintained between these substrates.

The ninth invention
In a photoelectric conversion element using alkali metal iodide, imidazolium iodide or quaternary ammonium iodide and iodine dissolved in a nonaqueous solvent as an electrolyte composition,
The total number of moles of the alkali metal iodide and the imidazolium iodide or quaternary ammonium iodide when the number of moles of the iodine added is 1 is equivalent to 50 times. To do.
Here, in the electrolyte composition, preferably, the amount of imidazolium iodide or quaternary ammonium iodide added is equivalent to 30 times the amount of iodine added, and the amount of alkali metal iodide added is iodine. The total molar concentration of alkali metal iodide and imidazolium iodide or quaternary ammonium iodide is 0.5 mol / l to 3.0 mol / l. Further, the alkali metal iodide includes at least one selected from the group consisting of LiI, NaI, and KI, for example. The non-aqueous solvent includes, for example, at least one selected from the group consisting of a nitrile solvent, a lactone solvent, and a carbonate solvent. One preferred specific example of the electrolyte composition (electrolyte) is methoxyacetonitrile solvent as a non-aqueous solvent, 0.1 mol / l of NaI as alkali metal iodide, and dimethylpropyl as imidazolium iodide. It is obtained by dissolving imidazolium iodine in an amount of 1.4 mol / l, iodine in an amount of 0.15 mol / l, and tert-butylpyridine as an additive in an amount of 0.2 mol / l. In this case, the electrolyte composition is prepared so that the total number of moles of NaI and dimethylpropylimidazolium iodine is 10 times that of iodine. In this electrolyte composition, it was confirmed that the photoelectric conversion characteristics of the photoelectric conversion element were the highest when the molar ratio of I ⁻ to I ₂ was 10: 1 and the molar concentration of I ⁻ was 1.5 mol / l. Has been.
In the ninth aspect, what has been described in relation to the first and second aspects of the invention other than the above is valid as long as not against the nature thereof.
According to the ninth aspect, the photoelectric conversion characteristics can be improved by using the above electrolyte composition.

  According to the present invention configured as described above, the non-mixing type two-component adhesive generally has sufficiently good adhesion and sealing properties. By bonding the first substrate and the second substrate, it is possible to effectively prevent, for example, volatilization or leakage of the electrolyte component, or intrusion of moisture, oxygen, and other components from the atmosphere into the electrolyte. And the performance degradation caused by it can be avoided. Further, there is no need for treatment such as heating, pressurization or ultraviolet irradiation at the time of bonding, and the durability against long-term use is high, and there is no possibility of adversely affecting the characteristics of the element. Furthermore, even a thin film substrate having a thickness of 100 μm or less, for example, can be reliably and easily attached to a predetermined position, and the productivity is high.

According to the present invention, it is possible to achieve a photoelectric conversion element such as a dye-sensitized solar cell that can obtain stable photoelectric conversion characteristics over a long period of time and is excellent in process compatibility. By using such a photoelectric conversion element such as an excellent dye-sensitized photoelectric conversion element, a high-performance photoelectric conversion element module, an electronic device, a moving body, and a power generation system can be obtained.
In addition, various displays that can obtain stable characteristics over a long period of time and are excellent in process compatibility can be realized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 shows a dye-sensitized solar cell according to a first embodiment of the present invention, FIG. 1A is a cross-sectional view, and FIG. 1B is a side view.
As shown in FIGS. 1A and 1B, in this dye-sensitized solar cell, a transparent electrode 2 and a semiconductor fine particle assembly layer 3 (semiconductor electrode) made of a metal oxide semiconductor are sequentially formed on a transparent substrate 1. And the electrode 5 (current collecting layer) and the counter electrode 6 sequentially formed on the substrate 4 in a state where the semiconductor fine particle assembly layer 3 and the counter electrode 6 face each other at a predetermined interval. In addition, the peripheral portions of the counter electrode 6 are bonded to each other by an adhesive 7. The distance between the semiconductor fine particle assembly layer 3 and the counter electrode 6 is, for example, 1 to 100 μm, typically several tens to 100 μm, preferably 1 to 50 μm. The adhesive 7 is formed using an unmixed two-component adhesive, and the thickness thereof is at least larger than the distance between the semiconductor fine particle assembly layer 3 and the counter electrode 6, and generally several tens of times. ˜100 μm. As this non-mixing type two-component adhesive, an adhesive whose curing proceeds by an addition reaction is preferably used. Moreover, in this non-mixing type two-component adhesive, the component causing the curing reaction is preferably 0.1 to 100%, more than the amount required when the reaction theoretically proceeds. Preferably, 5 to 20% more is used. An electrolyte layer 8 is enclosed in a space surrounded by the semiconductor fine particle assembly layer 3, the counter electrode 6, and the adhesive 7. Further, these components are housed in the case 9 and sealed. However, instead of being housed in the case 9, the whole may be resin-sealed. Both the transparent substrate 1 and the substrate 4 have, for example, a rectangular shape, but may have other shapes. The transparent electrode 2 and the counter electrode 6 are connected to each other by a conducting wire, and a load 10 is connected between them to form a current circuit 11. In this case, light is applied to the semiconductor fine particle assembly layer 3 from the transparent substrate 1 side.

The electrode 5 may be omitted as necessary. Further, in order to improve the adhesion between the counter electrode 6 and the electrode 5, or the adhesion between the counter electrode 6 and the substrate 4 when the electrode 5 is omitted, for example, a layer made of Cr or the like is interposed between them. Further, fine irregularities may be formed on the surface of the electrode 5 or the substrate 4. Further, the electrode 5 and the counter electrode 6 may be integrally formed. Examples of the material for the electrode 5 include, but are not limited to, glass, transparent conductive glass, metal, and polymer film. However, it is desirable that the material of the electrode 5 is a material that does not react even if it touches the electrolyte layer 8 when a pinhole is present in the counter electrode 6.
The transparent substrate 1 and the substrate 4 can be selected, for example, from those already mentioned, if necessary. Specifically, the transparent substrate 1 and the substrate 4 are made of, for example, a glass substrate or a transparent plastic substrate.

  The transparent electrode 2 is made of a transparent conductive material. More specifically, the transparent electrode 2 is, for example, an ITO single film, which is the most widely known transparent conductive material, doped with an element such as Zr, Hf, Te, F, etc. However, it may be formed by forming a laminated structure with a film of another transparent conductive material. As this laminated structure, for example, a structure in which a metal film such as Au, Ag, or Cu is laminated between ITO films or a structure in which a nitride layer is laminated between oxide layers can be used. It is not a thing.

As a material of the semiconductor fine particle joined body layer 3, for example, it can be selected as necessary from those already mentioned.
The semiconductor fine particles constituting the semiconductor fine particle sintered body layer 3 carry a sensitizing dye (not shown) and are sensitized by the sensitizing dye. As the sensitizing dye, for example, it can be selected from those already mentioned as required.
The electrolyte, redox system, solvent, and the like of the electrolyte layer 8 can be selected, for example, from those already listed as necessary. Further, a supporting electrolyte may be added to the electrolyte 8 as necessary. This supporting electrolyte can also be selected, for example, from among those already mentioned.

  As the counter electrode 6, a material made of platinum, platinum black, or the like, a material made of a conductive polymer, or a material made of carbon, particularly carbon carrying a metal and a binder polymer, or the like is used. As the conductive polymer, for example, it can be selected from those already mentioned as necessary. The form of carbon carrying metal may be basically any form, but preferably carbon nanotubes (including carbon nanohorns), acicular carbon, ketjen black, acetylene having a large specific surface area. Black etc. As the metal to be supported on carbon, at least one kind of metal selected from the group consisting of Pt, Ru, Co, Ti, Ni, Al and Au can be used, and the supported amount is, for example, 5 wt. % Or more. Moreover, as a binder polymer, it can select as needed from what was already mentioned, for example. Further, carbon or metal-supported carbon and a conductive polymer can be mixed or combined and used.

Next, the manufacturing method of this dye-sensitized solar cell is demonstrated.
First, a transparent substrate 1 on which a transparent electrode 2 is formed is prepared. Next, a paste in which semiconductor fine particles are dispersed is applied to a predetermined gap (thickness) on the transparent electrode 2 so that the planar shape is slightly smaller than the transparent electrode 2. Next, the transparent substrate 1 is heated to a predetermined temperature to sinter the semiconductor fine particles, thereby forming the semiconductor fine particle joined body layer 3.
Next, the semiconductor fine particles are loaded with the dye by, for example, immersing the transparent substrate 1 on which the semiconductor fine particle joined body layer 3 is formed in the dye solution. As a result, the semiconductor fine particle assembly layer 3 carrying the dye is formed.
On the other hand, a substrate in which an electrode 5 and a counter electrode 6 are formed on a substrate 4 is prepared separately.

  Then, as shown in FIG. 2, the first component 7a of the non-mixed two-component adhesive is applied to the peripheral portion of the surface of the transparent electrode 2 on the transparent substrate 1, and the first component 7a is formed. A thin film is formed. Further, as shown in FIG. 3, the second component 7b of the non-mixed two-component adhesive is applied to the peripheral portion of the surface of the counter electrode 6 on the substrate 4 to form a thin film made of the second component 7b. Form. The thickness of the thin film made of the second component 7b is the same as the thickness of the thin film made of the first component 7a. When the first component 7a and the second component 7b include a solvent component, the solvent component is removed by a method such as heating or decompression after the application of the first component 7a and the second component 7b. .

  Next, the transparent substrate 1 and the substrate 4 are arranged so that the semiconductor fine particle assembly layer 3 and the counter electrode 6 face each other at a predetermined interval, for example, 1 to 100 μm, preferably 1 to 50 μm. The thin film made of the first component 7a applied to the peripheral portion of the surface of the transparent electrode 2 and the thin film made of the second component 7b applied to the peripheral portion of the surface of the counter electrode 6 are bonded to each other. By adhering to this, the electrolyte layer 8 is injected from a liquid injection port formed in advance in the space between the semiconductor fine particle assembly layer 3 and the counter electrode 6. Thereafter, the liquid injection port is closed. Thereby, a dye-sensitized solar cell is manufactured.

The operation mechanism of this dye-sensitized solar cell is as follows.
Light incident from the transparent substrate 1 side excites the sensitizing dye carried on the semiconductor fine particle joined body layer 3, and the excited sensitizing dye quickly passes electrons to the semiconductor fine particle joined body layer 3. On the other hand, the sensitizing dye that has lost electrons receives electrons from the ions of the electrolyte layer 7 that is the carrier transfer layer. The molecule that has given the electron receives the electron at the counter electrode 6 again. In this way, a current flows between both poles. As described above, since the transparent electrode 2 and the counter electrode 6 are connected by the current circuit 11, the generated electrons flow to the counter electrode 6 through the semiconductor fine particle assembly layer 3. Thereby, electric energy can be taken out between the transparent electrode 2 and the counter electrode 6.

  As described above, according to the first embodiment, the semiconductor fine particle assembly layer 3, that is, the substrate 1 on which the semiconductor electrode is formed and the substrate 4 on which the counter electrode 6 is formed are not mixed two-component bonding. Adhesion and sealing are used to ensure that both the adhesiveness and sealing properties are sufficiently good, and there is no need for treatment by heating, pressurization or ultraviolet irradiation, and the element is not adversely affected. In addition, there is an advantage that durability against long-term use is high and compatibility with a manufacturing process is also high. For this reason, the dye-sensitized solar cell with a favorable photoelectric conversion characteristic over a long period of time can be obtained.

<Example 1>
A dye-sensitized solar cell was produced as follows.
TiO ₂ paste (trade name solaronix T) manufactured by solaronix is applied onto FTO glass (15Ω / □) manufactured by Nippon Sheet Glass Co., Ltd. using a doctor blade method and baked at 500 ° C. for 1 hour. An electrode was obtained. This titanium oxide electrode was immersed in a mixed solution of acetonitrile / tertiary butanol = 1/1 in which 0.3 mM N719 dye (manufactured by Kojima Chemical Co., Ltd.) was dissolved to adsorb the dye. The titanium oxide electrode on which the dye was adsorbed in this manner was washed with acetonitrile and then dried in the dark.
Subsequently, using a screen printing method, the first component of a 50 wt% toluene solution of an unmixed two-component silicone rubber adhesive (trade name HM-50) manufactured by Shin-Etsu Polymer Co., Ltd. It was applied to the part with a width of 2 mm. Similarly, the second component was applied on platinum sputtered glass.

Next, these electrodes are vacuum-dried at 50 ° C. for 0.5 hours to form a thin film composed of a first component and a second component of the unmixed two-component silicone rubber adhesive on both substrates, respectively. A layer was formed. Then, both substrates were bonded together so that these thin film layers were in contact with each other, and left for 5 hours at room temperature, thereby bonding both electrodes. The adhesive used here was mixed with a 50 μmφ spacer in order to keep the distance between both electrodes constant.
Thereafter, the electrolyte is injected from the electrolyte injection port provided on the counter electrode side in advance, and the injection port is sealed with a glass piece through a heat-sealing film, and then the periphery is covered with a one-component silicone rubber, A dye-sensitized solar cell was obtained.
Further, as shown in FIG. 4, six dye-sensitized solar cells 12 obtained in this way are connected in series by wirings 13, and each of the dye-sensitized solar cells 12 has an unmixed type 2 on the front surface and the back surface. The first component 7a and the second component 7b of the component type silicone rubber adhesive are applied, and the first component 7a and the second component 7b are applied to the PET resin 14, and each dye-sensitized solar cell is applied. The first component 7a applied to the surface of 12 and the second component 7b applied to the PET resin 14 are in contact with each other, and the second component 7b applied to the back surface of each dye-sensitized solar cell 12 and the PET These were laminated so that the first component 7a applied to the resin 14 was in contact with each other to obtain a solar cell module (AM 1.5 irradiation, open circuit voltage 4.5 V).

Next explained is a dye-sensitized solar cell according to the second embodiment of the invention.
In this dye-sensitized solar cell, in the semiconductor fine particle assembly layer 3, the dye molecules are adsorbed to the semiconductor fine particles by the acid functional groups, and some of the acid functional groups of the dye molecules are Li, Na. , K, tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, imidazolium compounds and neutralized by an alkali compound comprising a hydroxide of a compound selected from the group consisting of pyridinium compounds It is an anion. By doing so, association between the dye molecules is suppressed by the repulsive force acting between the anions, and an electron trap between the dye molecules can be greatly reduced. Others are the same as those of the dye-sensitized solar cell according to the first embodiment.

  This dye-sensitized solar cell is produced by, for example, preliminarily converting a part of acid functional groups of a dye molecule into Li, Na, K, tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium in a dye solution. The dye sensitization according to the first embodiment except that it is neutralized with an alkali compound comprising at least one metal selected from the group consisting of an imidazolium compound and a pyridinium compound or a hydroxide of a compound to form an anion. This is the same as the manufacturing method of the solar cell.

  According to the second embodiment, in addition to the same advantages as those of the first embodiment, the following advantages can be obtained. That is, by neutralizing a part of the acid functional group of the dye with an alkali compound, the acid functional group becomes an anion, and the repulsive force (charge repulsion) acting between the negative charges makes it difficult for the sensitizing dye molecules to associate with each other. Therefore, the electron traps between the dye molecules can be greatly reduced, whereby the current and voltage of the dye-sensitized solar cell can be greatly increased, and the photoelectric conversion efficiency can be improved.

<Example 2>
A dye-sensitized solar cell was produced in the same manner as in Example 1 except that the following process was used when the dye was supported on the titanium oxide electrode.
That is, fully purified cis-bis (isothiocyanate) -N, N-bis (2,2′-dipyridyl-4,4′-dicarboxylic acid) -ruthenium (II) dihydrate at a concentration of 1 mM. Dissolved in methanol. Next, 0.5 times the amount of carboxylic acid was added to this solution and stirred sufficiently to neutralize the carboxy group, and then concentrated with an evaporator and recrystallized with diethyl ether. The precipitate was separated by filtration, washed with diethyl ether, and dried by vacuum drying at 50 ° C. for 24 hours.

Next, the cis-bis (isothiocyanate) -N, N-bis (2,2 ′) thus obtained is obtained.
-The above-mentioned titanium oxide electrode was placed in a tert-butyl alcohol / acetonitrile mixed solvent (volume ratio 1: 1) in which dipyridyl-4,4'-dicarboxylic acid) -ruthenium (II) 2Na salt was dissolved at a concentration of 0.3 mM at room temperature. The sample was immersed for 24 hours to carry the dye. The titanium oxide electrode was washed with an acetonitrile solution of 4-tert-butylpyridine and then with acetonitrile and dried in the dark.
The dye-sensitized solar cell of Example 2 produced in this way has a drastically improved fill factor and open-circuit voltage compared to those using a dye without partial neutralization and a dye with complete neutralization, and photoelectric conversion. Excellent efficiency.

Next explained is a dye-sensitized solar cell according to the third embodiment of the invention.
As shown in FIG. 5, in this dye-sensitized solar cell, a transparent metal oxide layer 15 is provided on a transparent electrode 2, and a semiconductor fine particle joined body layer 3 is provided thereon. Specifically, for example, after forming the transparent electrode 2, an Nb ₂ O ₅ layer having a thickness of 20 nm is formed as the metal oxide layer 15 by a wet coating method, for example, a spray pyrolysis method. Others are the same as those of the dye-sensitized solar cell according to the first embodiment.

  According to the third embodiment, in addition to the same advantages as those of the first embodiment, the following advantages can be obtained. That is, the metal oxide layer 15 prevents the transparent electrode 2 and the electrolytic solution used as the electrolyte layer 8 from being in direct contact with each other, so that the leakage current due to the reverse electron transfer reaction can be greatly reduced. The factor and the open circuit voltage can be increased, and the photoelectric conversion efficiency can be further improved.

Next explained is a dye-sensitized solar cell according to the fourth embodiment of the invention.
As schematically shown in FIG. 6, in this dye-sensitized solar cell, not only the dye 16 is adsorbed to the semiconductor fine particle joined body layer 3 but also added to the gap portion between the dyes 16. The agent 17 is also adsorbed. In this case, no additive is added to the electrolyte solution constituting the electrolyte layer 8 unlike the conventional case. The pigment | dye 16 and the additive 17 can be selected as needed from what was already mentioned, for example. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

Next, the manufacturing method of this dye-sensitized solar cell is demonstrated.
First, similarly to the first embodiment, the transparent electrode 2 and the semiconductor fine particle assembly layer 3 are formed on the transparent substrate 1, and the dye 16 is adsorbed to the semiconductor fine particle assembly layer 3. The semiconductor fine particle assembly layer 3 in this state is schematically shown in FIG. 7A. The semiconductor fine particle assembly layer 3 is formed in the same manner as in the first embodiment.
Next, as shown in FIG. 7B, a solution 19 in which an additive 17 is dissolved in a solvent is placed in a container 18, and the transparent substrate 1 on which the semiconductor fine particle joined body layer 3 is formed is immersed in the solution 19. The container 18 is further covered with a lid 20 to adsorb the additive 17 to the semiconductor fine particle assembly 3. Specifically, as the solution 19, NaI 0.1M, 1-propyl-2,3 dimethylimidazolium iodide (DMP II) 0.6M, I ₂ 0.05M, an additive tert-butylpyridine (TBP) ) Prepare an electrolytic solution consisting of a 0.5M methoxyacetonitrile (MeACN) solution, immerse the semiconductor fine particle joined body layer 3 in this electrolytic solution for 5 to 10 minutes, and the semiconductor fine particle joined body at the site where the dye could not be adsorbed Tert-butylpyridine as an additive 52 was adsorbed on the surface of the layer 3. Thereafter, the electrolytic solution adhering to the semiconductor fine particle joined body layer 3 is rinsed off with methoxyacetonitrile and air-dried.

After adsorbing the additive 17 in this way, the transparent substrate 1 on which the semiconductor fine particle assembly layer 3 is formed is taken out from the container 18. Thereafter, the surface of the semiconductor fine particle assembly layer 3 is washed. The semiconductor fine particle assembly layer 3 in this state is schematically shown in FIG. 7C.
Thereafter, the process proceeds in the same manner as in the first embodiment, and the target dye-sensitized solar cell is manufactured.

  According to the fourth embodiment, the following advantages can be obtained in addition to the advantages similar to those of the first embodiment. That is, since the additive 17 is adsorbed in advance to the semiconductor fine particle assembly layer 3 to which the dye 16 is adsorbed and the electrolyte solution 8 is not added with the additive 17, the semiconductor fine particle assembly layer 3 is used. While the reverse electron transfer reaction is prevented by the additive 17 preliminarily adsorbed on the surface, the photoelectric conversion efficiency can be prevented from being deteriorated over time, and the lifetime can be improved.

Although the embodiments and examples of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments and examples, and various modifications based on the technical idea of the present invention are possible. It is.
For example, the numerical values, structures, shapes, materials, raw materials, processes, and the like given in the above-described embodiments and examples are merely examples, and numerical values, structures, shapes, materials, raw materials, processes, and the like that are different from these as necessary. May be used.

It is sectional drawing and the side view which show the dye-sensitized solar cell by 1st Embodiment of this invention. It is a top view for demonstrating the manufacturing method of the dye-sensitized solar cell by 1st Embodiment of this invention. It is a top view for demonstrating the manufacturing method of the dye-sensitized solar cell by 1st Embodiment of this invention. It is a top view which shows the solar cell module comprised by the dye-sensitized solar cell by Example 1 of this invention. It is sectional drawing which shows the dye-sensitized solar cell by 3rd Embodiment of this invention. It is sectional drawing which shows the dye-sensitized solar cell by 4th Embodiment of this invention. It is a schematic diagram for demonstrating the manufacturing method of the dye-sensitized solar cell by 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate, 2 ... Transparent electrode, 3 ... Semiconductor fine particle joined body layer, 4 ... Substrate, 5 ... Electrode, 6 ... Counter electrode, 7 ... Adhesive, 8 ... Electrolyte layer, 12 ... Dye-sensitized solar cell, 15 ... Metal oxide layer, 16 ... Dye, 17 ... Additive

Claims (19)

In the photoelectric conversion element having the first substrate and the second substrate facing each other,
The photoelectric conversion element, wherein the first substrate and the second substrate are bonded to each other with a non-mixed two-component adhesive.   2. The photoelectric conversion element according to claim 1, wherein the thickness of the adhesive layer made of the non-mixed two-component adhesive is 500 μm or less.   The photoelectric conversion element according to claim 1, wherein the curing reaction of the non-mixed two-component adhesive proceeds by an addition reaction.   The first substrate has a first electrode on a surface facing the second substrate, and the second substrate has a second electrode on a surface facing the first substrate. The photoelectric conversion element according to claim 1.   The photoelectric conversion element according to claim 4, wherein the first electrode is a semiconductor electrode made of a semiconductor fine particle assembly, and the second electrode is a counter electrode.   The photoelectric conversion element according to claim 1, wherein the photoelectric conversion element is a dye-sensitized solar cell. In a method for manufacturing a photoelectric conversion element having a first substrate and a second substrate facing each other,
The first component and the second component of the non-mixed two-component adhesive are applied to predetermined portions of the first substrate and the second substrate, respectively, and the first component applied to the first substrate is applied. The first substrate and the second substrate are bonded together so that the first component and the second component applied to the second substrate are in contact with each other. A method for producing a photoelectric conversion element, wherein the substrate is bonded to the substrate. In the photoelectric conversion element module in which a plurality of photoelectric conversion elements are arranged and wired,
At least one of the photoelectric conversion elements is
A first substrate and a second substrate facing each other;
The photoelectric conversion element module, wherein the first substrate and the second substrate are photoelectric conversion elements bonded to each other by a non-mixed two-component adhesive. In an electronic apparatus having a photoelectric conversion element having a first substrate and a second substrate facing each other,
The electronic device, wherein the first substrate and the second substrate are bonded to each other with a non-mixed two-component adhesive. In a moving body having a photoelectric conversion element having a first substrate and a second substrate facing each other,
The moving body, wherein the first substrate and the second substrate are bonded to each other with a non-mixing type two-component adhesive. In a power generation system having a photoelectric conversion element having a first substrate and a second substrate facing each other,
The power generation system, wherein the first substrate and the second substrate are bonded to each other by a non-mixed two-component adhesive. In a display having a first substrate and a second substrate facing each other,
The display according to claim 1, wherein the first substrate and the second substrate are bonded to each other by a non-mixed two-component adhesive. In a method for manufacturing a display having a first substrate and a second substrate facing each other,
The first component and the second component of the non-mixed two-component adhesive are applied to predetermined portions of the first substrate and the second substrate, respectively, and the first component applied to the first substrate is applied. The first substrate and the second substrate are bonded together so that the first component and the second component applied to the second substrate are in contact with each other. A method for manufacturing a display, characterized in that the substrate of 2 is bonded. In a photoelectric conversion element using alkali metal iodide, imidazolium iodide or quaternary ammonium iodide and iodine dissolved in a nonaqueous solvent as an electrolyte composition,
The total number of moles of the alkali metal iodide and the imidazolium iodide or quaternary ammonium iodide when the number of moles of the iodine added is 1, is equivalent to 50 times. A photoelectric conversion element.   15. The photoelectric conversion element according to claim 14, wherein the amount of the imidazolium iodide or the quaternary ammonium iodide added is equivalent to 30 times the amount of the iodine added.   The photoelectric conversion element according to claim 14, wherein the addition amount of the alkali metal iodide is 0.1 to 10 times the addition amount of the iodine.   The photoelectric conversion device according to claim 14, wherein the total molar concentration of the alkali metal iodide and the imidazolium iodide or quaternary ammonium iodide is 0.5 mol / l to 3.0 mol / l.   15. The photoelectric conversion element according to claim 14, wherein the alkali metal iodide contains at least one selected from the group consisting of LiI, NaI, and KI. 15. The photoelectric conversion element according to claim 14, comprising at least one selected from the group consisting of a nitrile solvent, a lactone solvent, and a carbonate solvent as the non-aqueous solvent.

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