JP4885511B2 - Method for producing dye-sensitized solar cell element - Google Patents

Description

  The present invention relates to a method for producing a dye-sensitized solar cell element.

  The dye-sensitized solar cell element announced by Gretzell et al. In 1991 is a wet solar cell using a titanium oxide porous thin film spectrally sensitized with a ruthenium complex as a working electrode, and can obtain performance equivalent to a silicon solar cell. (Non-Patent Document 1). Since this method can use an inexpensive oxide semiconductor such as titanium oxide without purifying it with high purity, it can provide an inexpensive photoelectric conversion element, and since the absorption of the dye is broad, it is possible to provide almost no visible light. There is an advantage that light in the entire wavelength region can be converted into electricity. However, on the other hand, since it is a wet solar cell in which electrical connection with the counter electrode is performed by an electrolyte solution, there is a concern that when used for a long period of time, the photoelectric conversion efficiency is remarkably lowered due to depletion of the electrolyte and the device does not function.

Under such circumstances, various sealing materials and installation methods are being studied in order to prevent electrolyte depletion over time in dye-sensitized solar cell elements.
For example, a method has been reported in which an epoxy resin, a silicon resin, or the like is used as a sealing resin, and the sealing portion is fixed with a solid material for sealing such as glass, metal, or plastic (Patent Document 1). However, as shown in FIG. 1, in this method, the sealing resin is installed at the cell substrate cross section, and these sealing resins are eroded or swollen by the solvent in the electrolyte solution, and the sealing solids Even if it is fixed by using, the contact portion with the electrolytic solution has a problem in long-term sealing performance.

In addition, a method has been reported in which a polyisobutylene resin is used as a base material for the sealing resin, a thermosetting polyisobutylene resin is used for the cell peripheral seal portion, and an ultraviolet curable polyisobutylene resin is used for the electrolyte inlet. (Patent Document 2). However, although the polyisobutylene-based resin can suppress the erosion or swelling of the solvent and iodine in the electrolyte solution, it is basically a curable sealing material, and the sealing at the periphery of the cell exhibits its sealing performance by thermosetting. Therefore, depending on the sensitizing dye used, there is a problem with respect to thermal stability, and the seal at the injection port is in contact with the electrolyte before UV curing, which may cause problems with insufficient curing or adhesion to the substrate. is there.
JP 2000-173680 A JP 2002-313443 A B. O'Regan, M. Gratzel, “Nature” (UK), 1991, 353, p. 737

  The present invention has been made in view of such a situation, and can produce a dye-sensitized solar cell element that can be produced without exposing the element to high temperatures and has long-term stability without impairing solar cell performance. A method is provided.

  That is, in the present invention, an electrode substrate having a semiconductor layer modified with a dye on a light-transmitting conductive substrate and a counter substrate having a catalyst layer on the conductive substrate are opposed to each other at a predetermined interval. A method of manufacturing a dye-sensitized solar cell element comprising an electrolyte between substrates and sealing a peripheral portion between the substrates with a sealing material, wherein the rubber has flexibility that can be deformed by external pressure as the sealing material After forming a cell by using a system material and providing a through-hole in a part of the seal, the inside of the cell is sealed by vacuum degassing, and then external pressure is applied to the cell It is related with the manufacturing method of the dye-sensitized solar cell element characterized by adjusting the space | interval between board | substrates to a predetermined space | interval.

The present invention is described in detail below.
1 and 2 are schematic cross-sectional views of a dye-sensitized solar cell element produced by a conventional technique.
FIG. 1 shows a state in which a conductive substrate 2 having a catalyst layer 4 and a transparent conductive substrate 1 having a semiconductor layer 3 modified with a dye are overlapped, and an electrolyte is soaked between the substrates, and then the periphery of the cell is epoxy resin or the like In addition to the sealing material, a cell is produced by sealing using a sealing solid such as plastic.
FIG. 2 shows a cell in which a sealing material is applied to the periphery of the cell when the conductive substrate 2 having the electrolyte inlet 9 and the catalyst layer 4 and the transparent conductive substrate 1 having the semiconductor layer 3 modified with the dye are overlapped. Then, an electrolyte is injected from the injection port, and then the injection port is sealed to manufacture a cell.

  FIG. 3 is an example of a schematic cross-sectional view of a dye-sensitized solar cell element produced by the method of the present invention. FIG. 4 is an example of a schematic diagram regarding installation of the sealing material in the present invention, and a through-hole for vacuum degassing inside the cell is provided. FIG. 5 is an example showing a method of vacuum degassing a cell provided with a seal as shown in FIG. In this vacuum degassing step, the through-hole is sealed by bonding the sealing materials.

  As shown in FIG. 3, the dye-sensitized solar cell element according to the present invention includes an electrode substrate having a semiconductor layer 3 modified with a dye on a light-transmitting conductive substrate 1, and a conductive substrate 2. This is a configuration in which a counter substrate having a catalyst layer 4 thereon is opposed to each other at a predetermined interval, an electrolyte 5 is disposed between these substrates, and a sealing material 6 is disposed at a peripheral portion between the substrates.

In the present invention, a rubber material is used as the sealing material. The rubber-based material used in the present invention has adhesiveness to both substrates facing each other at a predetermined interval, and has a flexibility that can be deformed by an external pressure in order to control a predetermined gap. It is necessary to be.
As a rubber-based sealing material that can be deformed by such external pressure and has flexibility, the inside of the cell is sealed and isolated from the outside, and components that affect the performance of the element, such as moisture, oxygen, monoxide, etc. There is no particular limitation on the type of the active gas such as carbon as long as it can prevent penetration of the active gas into the device. Examples of these are natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, butyl rubber, ethylene propylene rubber, chloroprene rubber, chlorosulfonated polyethylene, nitrile rubber, urethane rubber, polysulfide rubber, acrylic rubber, epichlorohydrin rubber, silicone. Synthetic rubbers such as rubber, fluororubber and hydrogenated nitrile rubber can be preferably used. These rubber components may be filled with a filler such as glass.

The method for installing the sealing material on the peripheral portions of the opposing substrates is not particularly limited, and any method can be adopted. For example, the following methods (1) to (3) can be mentioned.
(1) A method in which a material that has been processed and molded into a shape to be sealed in advance is produced and then sandwiched between substrates.
(2) A method of applying a sealing material to the substrate surface as needed (3) A method of forming an arbitrary pattern on the substrate by sweeping the sealing material while discharging it from the nozzle. It may be applied to both or only one of them.

In the present invention, a through-hole is provided in a part of the seal portion. The through-hole acts as a deaeration port for removing gas such as oxygen contained in the electrolyte installed inside the cell. In the present invention, by using a rubber-based material having flexibility that can be deformed by an external pressure as the sealing material, the inside of the cell is evacuated to become a vacuum, and the sealing material is deformed to close the through hole. By doing so, sealing advances. Therefore, the sealing work for manufacturing the element is not required, and the work can be simplified.
The size of the through-hole of the seal part is not particularly limited, as long as the through-hole part is deformed by external pressure under vacuum and can be closed and sealed, preferably 0.1 mm to 5 mm wide, more preferably 0.5 mm to 2 mm wide It is preferable to set to.
Further, the number of through-holes installed in the seal portion is not particularly limited as long as the inside of the cell can be vacuum degassed. However, considering the installation effort, it is preferably 20 or less, and more preferably 10 or less.

  As a method for performing vacuum treatment inside the cell, for example, as shown in FIG. 5, the cell is inserted into a bag-like pack made of plastic or the like loaded with a jig that can be evacuated, and degassed under vacuum. Any method can be used as long as the cell can be vacuum-processed.

As a method for adjusting the distance between the substrates, since the inside of the cell is vacuum, it is possible to obtain a predetermined distance by applying external pressure to the cell. For example, it can be achieved by placing the cell in a pressure press or the like and pressurizing until the sealing material reaches a predetermined thickness, but any method can be used as long as the method can uniformly apply an external pressure to the cell.
Further, the gap width between the substrates can be adjusted by previously mixing the spacer material in the sealing material. The spacer material needs to be non-conductive, but the shape may be any shape such as a sheet shape, a spherical shape, a fiber shape, or a rod shape. Examples thereof include glass beads, plastic beads, glass fibers, and plastic fibers.
The diameter of the spacer material is not particularly limited, but is preferably 300 μm or less, more preferably 100 μm or less.

The electrode substrate (photoelectrode) of the dye-sensitized solar cell element in the present invention is composed of a conductive substrate having optical transparency and a semiconductor layer containing a photosensitized dye.
A light-transmitting conductive substrate usually has a transparent electrode layer on a transparent substrate.
The transparent substrate is not particularly limited, and the material, thickness, dimensions, shape, and the like can be appropriately selected according to the purpose. For example, colorless or colored glass, meshed glass, glass block, etc. are used, and colorless. Alternatively, a colored transparent resin may be used. Examples of such resins include polyesters such as polyethylene terephthalate, polyamide, polysulfone, polyether sulfone, polyether ether ketone, polyphenylene sulfide, polycarbonate, polyimide, polymethyl methacrylate, polystyrene, cellulose triacetate, and polymethylpentene. The term “transparent” in the present invention means a transmittance of 10 to 100%, preferably a transmittance of 50% or more, and the substrate in the present invention has a smooth surface at room temperature. The surface may be a flat surface or a curved surface, or may be deformed by stress.

Moreover, it does not specifically limit as a transparent electrode layer which acts as an electrode, For example, the electrically conductive film etc. which consist of metal thin films, such as gold | metal | money, silver, chromium, copper, tungsten, a metal oxide, etc. are mentioned. Examples of the metal oxide include Indium Tin Oxide (ITO (In ₂ O ₃ : Sn)) obtained by doping a metal oxide such as tin and zinc with a small amount of other metal elements, Fluorine doped Tin Oxide (FTO (SnO ₂ )). : F)), Aluminum doped Zinc Oxide (AZO (ZnO: Al)) and the like are preferably used.
The film thickness of the conductive film is usually 10 to 5000 nm, preferably 100 to 3000 nm. The surface resistance (resistivity) is appropriately selected, but is usually 0.5 to 500 Ω / sq, preferably 1 to 50 Ω / sq.

The method for forming the transparent electrode layer is not particularly limited, and a known method is appropriately selected and used depending on the type of the metal or metal oxide used as the electrode layer. Usually, the vacuum deposition method, the ion plating method are used. CVD method, sputtering method, or the like is used. In any case, it is desirable that the substrate is formed within a range of 20 to 700 ° C.
When the surface resistance needs to be further reduced, a thin metal wire such as silver or gold may be provided on the conductive substrate.

The semiconductor used in the present invention is not particularly limited, for _{example, Bi 2 S 3, CdS,} CdSe, CdTe, CuInS 2, CuInSe 2, Fe 2 O 3, GaP, GaAs, InP, Nb 2 O 5, PbS , Si, SnO ₂ , TiO ₂ , WO ₃ , ZnO, ZnS and the like, preferably CdS, CdSe, CuInS ₂ , CuInSe ₂ , Fe ₂ O ₃ , GaAs, InP, Nb ₂ O ₅ , PbS, SnO _2. , TiO ₂ , WO ₃ , ZnO, and a plurality of combinations may be used. Particularly preferred are TiO ₂ , ZnO, SnO ₂ and Nb ₂ O ₅ , and most preferred are TiO ₂ and ZnO.

The semiconductor used in the present invention may be single crystal or polycrystalline. As the crystal system, anatase type, rutile type, brookite type and the like are mainly used, and anatase type is preferable. A known method can be used for forming the semiconductor layer.
As a method for forming the semiconductor layer, the semiconductor nanoparticle dispersion, the sol solution, or the like can be obtained by coating on a substrate by a known method. The coating method in this case is not particularly limited, and various printing methods including a screen printing method, in addition to a method obtained in a thin film state by a casting method, a spin coating method, a dip coating method, and a bar coating method. Can be mentioned.
Although the thickness of a semiconductor layer is arbitrary, it is 0.1 micrometer-300 micrometers normally, Preferably it is 1 micrometer-50 micrometers.

In the dye-sensitized solar cell element of the present invention, a semiconductor layer modified with a dye (adsorption, inclusion, etc.) is used for the purpose of improving the light absorption efficiency of the semiconductor layer.
The dye that can be used in the present invention is not particularly limited as long as it is a dye that improves the light absorption efficiency of the semiconductor layer. Usually, one or more of various metal complex dyes and organic dyes are used. Can be used. In addition, in order to impart adsorptivity to the semiconductor layer, a functional group such as a carboxyl group, a hydroxyl group, a sulfonyl group, a phosphonyl group, a carboxylalkyl group, a hydroxyalkyl group, a sulfonylalkyl group, or a phosphonylalkyl group is included in the dye molecule. Those having a group are preferably used.
As the metal complex dye, a complex of ruthenium, osmium, iron, cobalt, zinc, metal phthalocyanine, chlorophyll, or the like can be used.

  As the organic dye, a cyanine dye, a hemicyanine dye, a merocyanine dye, a xanthene dye, a triphenylmethane dye, or a metal-free phthalocyanine dye can be used.

  As a method for adsorbing the dye to the semiconductor layer, a solution in which the dye is dissolved in a solvent is applied on the semiconductor layer by spray coating or spin coating and then dried. In this case, the substrate may be heated to an appropriate temperature. Alternatively, a method in which a semiconductor layer is immersed in a solution and adsorbed can be used. The immersion time is not particularly limited as long as the dye is sufficiently adsorbed, but is preferably 1 to 30 hours, particularly preferably 5 to 20 hours. Moreover, you may heat a solvent and a board | substrate when immersing as needed. Preferably, the concentration of the dye in the case of a solution is about 1 to 1000 mM / L, preferably about 10 to 500 mM / L.

  The solvent to be used is not particularly limited as long as it does not dissolve the dye and does not dissolve the semiconductor layer, such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and t-butanol. Nitrile solvents such as alcohol, acetonitrile, propionitrile, methoxypropionitrile, glutaronitrile, benzene, toluene, o-xylene, m-xylene, p-xylene, pentane, heptane, hexane, cyclohexane, heptane, acetone, Methyl ethyl ketone, diethyl ketone, 2-butanone, diethyl ether, tetrahydrofuran, ethylene carbonate, propylene carbonate, nitromethane, dimethylformamide, dimethyl sulfoxide, hexamethylphosphoamide, dimethoxy ester , Γ-butyrolactone, γ-valerolactone, sulfolane, dimethoxyethane, adiponitrile, methoxyacetonitrile, dimethylacetamide, methylpyrrolidinone, dimethylsulfoxide, dioxolane, sulfolane, trimethyl phosphate, triethyl phosphate, tripropyl phosphate, ethyl phosphate Dimethyl, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, trinonyl phosphate, tridecyl phosphate, tris phosphate (trifluoromethyl), tris phosphate (pentafluoroethyl), Triphenyl polyethylene glycol phosphate, polyethylene glycol and the like can be used.

The counter electrode of the dye-sensitized solar cell element in the present invention is composed of a counter substrate having a catalyst layer on a conductive substrate.
The conductive substrate only needs to be conductive or have at least one surface conductive, and may be a transparent transparent conductive substrate or an opaque conductive substrate. As an opaque conductive substrate, in addition to various metal electrodes, for example, Au, Pt, Cr formed on a glass substrate can be exemplified.
The catalyst layer is for advancing the reduction reaction of the redox couple of the electrolyte, and any material having a catalytic function can be used. Examples of the material for forming such a catalyst layer include noble metals such as platinum, conductive organic compounds such as polydioxythiophene and polypyrrole, and carbon.
The formation method in particular of a catalyst layer is not restrict | limited, A well-known method is employable. For example, in the case of platinum or the like, it can be produced by a generally known vacuum deposition method, ion plating method, CVD method or sputtering method. In addition, the catalyst-forming material and the binder are mixed to form a paste, and screen printing, flat printing, gravure printing, intaglio printing, flexographic printing, letterpress printing, special printing on a conductive substrate surface, doctor blade method, etc. Can also be manufactured.

The electrolyte used in the present invention is not particularly limited, and may be either a liquid system or a solid system, and desirably exhibits reversible electrochemical redox characteristics.
The liquid electrolyte is not particularly limited. Usually, a solvent, a substance exhibiting reversible electrochemical redox characteristics (soluble in a solvent), and, if necessary, a supporting electrolyte as a basic component Composed.

  Any solvent can be used as long as it is generally used in electrochemical cells and batteries. Specifically, acetic anhydride, methanol, ethanol, tetrahydrofuran, propylene carbonate, nitromethane, acetonitrile, dimethylformamide, dimethyl sulfoxide, hexamethylphosphoamide, ethylene carbonate, dimethoxyethane, γ-butyrolactone, γ-valerolactone, sulfolane, dimethoxy Ethane, propiononitrile, glutaronitrile, adiponitrile, methoxyacetonitrile, dimethylacetamide, methylpyrrolidinone, dimethyl sulfoxide, dioxolane, sulfolane, trimethyl phosphate, triethyl phosphate, tripropyl phosphate, ethyldimethyl phosphate, tributyl phosphate, phosphorus Tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, trinonyl phosphate, phosphoric acid Tridecyl, tris phosphate (trifluoromethyl), tris phosphate (pentafluoroethyl), triphenyl polyethylene glycol phosphate, polyethylene glycol, and the like can be used. In particular, propylene carbonate, ethylene carbonate, dimethyl sulfoxide, dimethoxyethane, acetonitrile, γ-butyrolactone, sulfolane, dioxolane, dimethylformamide, dimethoxyethane, tetrahydrofuran, adiponitrile, methoxyacetonitrile, methoxypropionitrile, dimethylacetamide, methylpyrrolidinone, dimethylsulfoxide , Dioxolane, sulfolane, trimethyl phosphate and triethyl phosphate are preferred.

  Moreover, room temperature molten salts can also be used as a solvent. Here, the room temperature molten salt is a salt composed of an ion pair that is melted at room temperature (that is, in a liquid state) and usually has a melting point of 20 ° C. or lower and is a liquid at a temperature exceeding 20 ° C. Is a salt.

In addition, examples of substances that exhibit reversible electrochemical oxidation-reduction characteristics include what are commonly referred to as so-called redox materials, but the type is not particularly limited. Examples of such substances include ferrocene, p-benzoquinone, 7,7,8,8-tetracyanoquinodimethane, N, N, N ′, N′-tetramethyl-p-phenylenediamine, tetrathiafulvalene, thi Anthracene, p-toluylamine, etc. can be mentioned. Further, LiI, NaI, KI, CsI , CaI 2, 4 quaternary imidazolium iodide salt, iodine tetraalkylammonium Motoshio, Br ₂ and LiBr, NaBr, KBr, CsBr, and metal bromides, such as CaBr ₂ and the like, In addition, Br ₂ and tetraalkylammonium bromide, bipyridinium bromide, bromine salts, complex salts such as ferrocyanic acid-ferricyanate, sodium polysulfide, alkylthiol-alkyldisulfides, hydroquinone-quinones, viologen dyes and the like can be mentioned. .

As the redox material, only one of an oxidant and a reductant may be used, or the oxidant and the reductant may be mixed and added at an appropriate molar ratio. Further, these redox pairs may be added so as to show electrochemical responsiveness. Materials exhibiting such properties include halogen ions, SCN ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N _{^{-, PF 6 -, AsF 6}} -, CH 3 COO -, CH 3 (C 6 H 4) SO 3 -, and _{(C 2 F 5 SO 2)} 3 C - , such as ferrocenium having a counter anion selected from metallocenium of In addition to salts, halogens such as iodine, bromine and chlorine can also be used.

In addition, redox room temperature molten salts can also be used as substances exhibiting reversible electrochemical redox properties. Here, the redox room temperature molten salt is a salt composed of an ion pair melted at room temperature (that is, in a liquid state), and usually has a melting point of 20 ° C. or lower and is a liquid at a temperature exceeding 20 ° C. A salt consisting of a pair is shown, and a reversible electrochemical redox reaction can be performed.
The redox room temperature molten salt can be used alone or in combination of two or more.

  The amount of the substance exhibiting reversible electrochemical redox characteristics is not particularly limited as long as it dissolves in the solvent, but is usually 1% by mass to 50% by mass, preferably 3% with respect to the solvent. It is desirable that it is mass%-30 mass%.

Further, as the supporting electrolyte added as necessary, salts, acids, alkalis, and room temperature molten salts that are usually used in the field of electrochemistry or the field of batteries can be used.
The salt is not particularly limited, and examples thereof include inorganic ion salts such as alkali metal salts and alkaline earth metal salts, quaternary ammonium salts, cyclic quaternary ammonium salts, and quaternary phosphonium salts. preferable.

  The electrolyte may be a liquid as described above, but a polymer solid electrolyte (ion conductive film) may be used. Particularly preferable examples of the polymer solid electrolyte include a polymer matrix containing a substance exhibiting at least reversible electrochemical redox characteristics in a polymer matrix, and further containing a plasticizer if desired. In addition to these, other optional components such as the above-mentioned supporting electrolyte and room temperature molten salt may be further contained as desired.

  The material that can be used as the polymer matrix is not particularly limited as long as a solid state or gel state is formed by the polymer matrix alone, or by the addition of a plasticizer, the addition of a supporting electrolyte, or the addition of a plasticizer and a supporting electrolyte. In general, so-called polymer compounds that are generally used can be used.

  Examples of the polymer compound exhibiting characteristics as the polymer matrix include hexafluoropropylene, tetrafluoroethylene, trifluoroethylene, ethylene, propylene, acrylonitrile, vinylidene chloride, acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, and methyl methacrylate. And polymer compounds obtained by polymerizing or copolymerizing monomers such as styrene and vinylidene fluoride. These polymer compounds may be used alone or in combination. Among these, a polyvinylidene fluoride polymer compound is particularly preferable.

  The thickness of the electrolyte layer is not particularly limited, but is preferably 1 μm or more, more preferably 10 μm or more, and preferably 3 mm or less, more preferably 1 mm or less, and still more preferably 0.5 mm or less.

  As described above, according to the present invention, a solar cell element can be manufactured without being exposed to a high temperature. Therefore, a solar cell element with good durability can be manufactured without impairing the performance of the element.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[Example 1]
On a 10 cm square ITOF glass having a surface resistance of 2Ω / sq, a titania paste Ti-Nanoxide T / SP manufactured by SOLARONIXS was applied by a screen printing method and dried at 100 ° C. Next, the coated substrate was baked at 450 ° C. for 30 minutes. When the film thickness of the titania semiconductor layer after firing was measured with a stylus type film thickness meter, it was found to be 12 μm.
This substrate was immersed in a ruthenium dye / ethanol solution (3.0 × 10 ⁻⁴ mol / L) represented by the following formula (1) for 15 hours to adsorb the dye. On the periphery of the four sides of this substrate, 50 μm glass beads mixed with butyl rubber and processed into a sheet having a thickness of 500 μm and a width of 0.5 mm was attached. In addition, through holes were provided with a width of 1 mm at the corners of the substrate. After inserting a predetermined amount of a methoxypropionitrile solution containing 0.5 mol / L lithium iodide, 0.05 mol / L iodine and 0.5 mol / L 4-t-butylpyridine on the obtained substrate, The counter electrode having a Pt film with a film thickness of 30 nm on the titanium plate was combined, and then inserted into a nylon bag as shown in FIG. Further, this cell was pressed at room temperature using a pressure press machine to produce an element having a substrate spacing of 50 μm.
A lead wire was connected to the conductive layer portion of the transparent conductive substrate and the counter electrode.
When the device thus obtained was irradiated with AM1.5G pseudo-sunlight and the current-voltage characteristics were measured, good photoelectric conversion characteristics (conversion efficiency 5.1%) were obtained.
Further, as a result of evaluating this device after being left at room temperature for 1000 hours, the photoelectric conversion characteristics (conversion efficiency 5.0%) hardly changed, and no liquid leakage was observed.

[Example 2]
An element manufactured in the same manner as in Example 1 was evaluated after being left for 200 hours in an environment at 80 ° C. As a result, although the photoelectric conversion characteristics (conversion efficiency 4.1%) were lowered, no liquid leakage or the like was observed.

[Example 3]
A gel electrolyte film was prepared as follows.
6 g of a poly (vinylidene fluoride-hexafluoropropylene) block copolymer (hexafluoropropylene content: 5% by weight) was dissolved in a mixed solvent of 14 g of γ-butyrolactone and 15 g of acetone.
To this solution, 230 mg of iodine, 1.2 g of lithium iodide and 6.0 g of 4-t-butylpyridine were added and dissolved by heating, then cooled to room temperature, coated on a glass substrate, and acetone was vaporized. Removed.
A device was produced by the method shown in Example 1 except that the electrolyte film obtained by the above method was used instead of the electrolyte used in Example 1.
When the device thus obtained was irradiated with AM1.5G pseudo-sunlight and the current-voltage characteristics were measured, good photoelectric conversion characteristics (conversion efficiency 4.8%) were obtained.
Further, as a result of evaluating this device after being left at room temperature for 1000 hours, the photoelectric conversion characteristics (conversion efficiency 4.7%) hardly changed, and no liquid leakage or the like was observed.

[Example 4]
An element manufactured in the same manner as in Example 3 was evaluated after being left for 200 hours in an environment of 80 ° C. As a result, although the photoelectric conversion characteristics (conversion efficiency 3.9%) were reduced, no liquid leakage was observed.

[Example 5]
A gel electrolyte precursor was prepared as follows.
3 g of Kynar 2501 (poly (vinylidene fluoride-hexafluoropropylene), manufactured by Atofina) was dissolved in 17 g of γ-butyrolactone, 50 mg of diethylamine was added, and the reaction was performed at 100 ° C. for 2 hours.
Next, 230 mg of iodine and 1.2 g of lithium iodide were added to this reaction solution, and after heating and dissolving, the solution was cooled to room temperature, and 50 mg of 1,4-cyclohexanediamine was added thereto.
A cell was prepared in the same manner as in Example 1 except that the obtained gel electrolyte precursor was used, and this cell was left overnight to complete the curing of the gel electrolyte.
When the device thus obtained was irradiated with AM1.5G pseudo-sunlight and the current-voltage characteristics were measured, good photoelectric conversion characteristics (conversion efficiency 4.8%) were obtained.

[Comparative Example 1]
A thermosetting resin in which 50 μm glass beads were mixed as a sealing material was applied to the periphery of the electrode substrate manufactured in Example 1 using a dispenser method. An electrolyte injection port portion having a width of 2 mm was provided in a part of the seal portion. On top of this, the counter electrode produced in Example 1 was combined, and then the sealing material was cured at 100 ° C. for 30 minutes.
The distance between the substrates of the obtained cells was 50 μm. The cell was filled with the same electrolytic solution as in Example 1 by vacuum injection, and the injection port was sealed with a photocurable epoxy adhesive.
A lead wire was connected to the conductive layer portion of the transparent conductive substrate and the counter electrode.
When the device thus obtained was irradiated with AM1.5G pseudo-sunlight and the current-voltage characteristics were measured, photoelectric conversion characteristics (conversion efficiency 3.7%) were obtained.
Since the cell was exposed to the curing temperature of the sealing material as described above, the photoelectric conversion efficiency was significantly reduced as compared with Example 1.
Moreover, as a result of evaluating this element after being left at room temperature for 1000 hours, liquid leakage from the inlet sealing portion was observed.

It is sectional drawing which shows the dye-sensitized solar cell element of a prior art example. It is sectional drawing which shows the dye-sensitized solar cell element of a prior art example. It is an example of the cross-sectional schematic which shows the dye-sensitized solar cell element of this invention. It is the schematic which shows an example of sealing material installation. It is the schematic which shows an example of the vacuum deaeration method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent conductive substrate 2 Conductive substrate 3 Semiconductor layer modified with dye 4 Catalyst layer 5 Electrolyte 6 Sealing material 8 Through-hole 9 Inlet 10 Sealing material 11 Solid material for sealing 12 Electrolyte 13 Pre-sealing solar cell 14 Vacuum bag 15 Vacuum drawing jig

Claims (2)

  An electrolyte is interposed between a substrate in which an electrode substrate having a semiconductor layer modified with a dye on a conductive substrate having light transmittance and a counter substrate having a catalyst layer on the conductive substrate are opposed to each other with a predetermined interval. And a method for producing a dye-sensitized solar cell element in which a peripheral portion between the substrates is sealed with a sealing material, using a rubber-based material having flexibility that can be deformed by external pressure as the sealing material, In addition, after forming a cell by providing a through hole in a part of the seal portion, the inside of the cell is vacuum degassed to seal the through hole, and then an external pressure is applied to the cell to increase the spacing between the substrates. A method for producing a dye-sensitized solar cell element, characterized by adjusting to a predetermined interval. A dye-sensitized solar cell element produced by the method according to claim 1.

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