JP4637474B2 - Dye-sensitized solar cell - Google Patents

Description

  The present invention relates to a dye-sensitized solar cell suitable for use in an outdoor environment.

  In recent years, there has been great interest in photocatalytic technology utilizing metal oxide semiconductors, and various studies have been conducted. For example, practical application studies are progressing in the fields of decomposition of harmful organic substances, removal of air pollutants, sterilization and antibacterial. Recently, attention has been focused on the photovoltaic action of metal oxide semiconductors. A dye-sensitized solar cell is one that utilizes this photovoltaic action (Japanese Patent Laid-Open No. 2000-294814 (Patent Document 1) and the like).

  In such a dye-sensitized solar cell, a metal oxide semiconductor film on which a dye is adsorbed is used as a semiconductor electrode. When the semiconductor electrode thin film is irradiated with light such as sunlight, the light is absorbed by the dye, and the dye that has absorbed the light is excited. The excited dye quickly passes electrons to the metal oxide, and the electrons travel through the metal oxide and flow to the electrode. After releasing the electrons, the positively charged dye receives electrons from the electrolyte and returns to neutral. That is, in the dye-sensitized solar cell, the semiconductor electrode functions as a negative electrode and the counter electrode functions as a positive electrode.

JP 2000-294814 A

  As described above, dye-sensitized solar cells operate by receiving sunlight and are usually used in outdoor environments. However, outdoors, it is expected to be affected by various environmental factors. In particular, contamination of a dye-sensitized solar cell with atmospheric environmental pollutants is an unavoidable problem.

  Specifically, when environmental pollutants such as dust, dust, dust, and sand floating in the atmosphere adhere to the surface of the solar cell, visible light from sunlight necessary for the operation of the dye-sensitized solar cell is Environmental pollutants may be absorbed or reflected, blocking the entry of light into the dye-sensitized solar cell. Thereby, the performance of a solar cell will fall remarkably. The influence of this environmental pollutant becomes greater as the period of outdoor use is longer.

In the dye-sensitized solar cell, currently, there are almost no measures against the environmental pollutants as described above.
The present invention has been made in view of such problems, and an object of the present invention is to suppress a decrease in performance of a dye-sensitized solar cell due to an environmental pollutant in the atmosphere.

  In order to solve the above-mentioned problem, the present inventor has made extensive studies and as a result, a coating film having a contact angle of 70 ° or less is formed on at least one outer surface of the dye-sensitized solar cell. As a result, the present invention was completed.

That is, the present invention has the following characteristics.
1. First substrate (a), first conductive layer (b), metal oxide semiconductor layer (c) having a photosensitizer, electrolyte layer (d), second conductive layer (e), second substrate (f) Are sequentially stacked, and a first stacked body (I) composed of the first substrate (a) to the first conductive layer (b), and a second stacked body (II) composed of the electrolyte layer (d) to the second substrate (f). ) Is a solar cell having transparency,
A film having a contact angle with respect to water of 70 ° or less is formed on the outer surface of the first laminate (I) and / or the second laminate (II), and the coat comprises (h) an alkoxysilane compound, ( A dye-sensitized solar cell formed by a film-forming composition comprising i) a catalyst, (j) water, (k) a solvent, and (l) a quaternary cation base-containing polymer .
2. 1. A film having a contact angle with water of 70 ° or less is further formed of a film-forming composition containing (m) a metal oxide sol having a particle diameter of 3 to 100 nm . The dye-sensitized solar cell described.

  According to the present invention, by forming a film having a contact angle of 70 ° or less on at least one outer surface of a dye-sensitized solar cell, environmental pollutants attached to the solar cell surface can be removed by a self-cleaning function. Thus, the performance of the solar cell can be maintained for a long time. Further, it is not necessary to clean the surface of the solar cell, and the running cost for maintaining the performance of the solar cell is reduced.

  Hereinafter, the present invention will be described in detail based on the embodiments.

  The present invention includes a first substrate (a), a first conductive layer (b), a metal oxide semiconductor layer (c) having a photosensitizer, an electrolyte layer (d), a second conductive layer (e), a second Applied to a solar cell having a configuration in which the substrates (f) are sequentially stacked, that is, a configuration in which (b) to (e) are provided inside the first substrate (a) and the second substrate (f). It is. Among these, the laminated body composed of the first substrate (a) to the first conductive layer (b) is the first laminated body (I), and the laminated body composed of the electrolyte layer (d) to the second substrate (f) is the second laminated body. Called body (II).

As a 1st board | substrate (a) in 1st laminated body (I), what has transparency, such as a glass plate and a polymer film, is normally used. Among these, when a polymer film is used as the substrate, the flexibility of the laminate is enhanced, and the weight and thickness can be reduced. Also, there is no need to worry about the substrate breaking.
The first conductive layer (b) is a layer having a conductive compound, and is provided on one side of the first substrate (a). As the conductive compound, for example, tin oxide, fluorine-doped tin oxide, indium oxide, tin oxide-doped indium oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, or the like can be used. Also, various metals can be used as long as the conductivity is not impaired. The first conductive layer (b) can be obtained, for example, by depositing or laminating a conductive compound on the first substrate (a).

The metal oxide in the metal oxide semiconductor layer (c) is a component that plays a role of passing electrons excited by the photosensitizer to the electrode.
Examples of the metal oxide include titanium oxide, lanthanum oxide, zirconium oxide, niobium oxide, tungsten oxide, strontium oxide, zinc oxide, tin oxide, and indium oxide. Among these, titanium oxide is preferable, and anatase type titanium oxide is particularly preferable. The primary particle diameter of the metal oxide is usually 1 to 200 nm, preferably 3 to 50 nm, more preferably 5 to 30 nm.

The metal oxide semiconductor layer (c) can be formed by fixing the above metal oxide with a binder or the like. As the binder, titanium hydroxide is suitable.
The constituent ratio of the metal oxide in the metal oxide semiconductor layer (c) is usually 60 to 99% by weight, preferably 70 to 90% by weight. The constituent ratio of the binder is usually 1 to 40% by weight, preferably 10 to 30% by weight.
The film thickness of the metal oxide semiconductor layer (c) is usually 1 to 100 μm, preferably 5 to 50 μm.

A photosensitizer is adsorbed on the metal oxide semiconductor layer (c). This photosensitizer has a function of absorbing visible light to excite electrons and transmitting the electrons to the metal oxide.
The photosensitizer can be used without particular limitation as long as it has such a function, and examples thereof include organic dyes and metal complexes. Examples of organic dyes that can be used include metal-free phthalocyanine, cyanine dyes, merocyanine dyes, xanthene dyes, and triphenylmethane dyes. As the metal complex, for example, copper phthalocyanine, titanyl phthalocyanine, chlorophyll, hemin, and complexes of ruthenium, osmium, iron, zinc and the like described in JP-A-1-220380 and JP-B-5-504023 can be used. .

As the electrolyte in the electrolyte layer (d), those usually used in dye-sensitized solar cells can be used. Specifically, for example, ^I - / I ₃ ^- system, Br ^- / Br ₃ ^- system, quinone / hydroquinone system. Such an electrolyte can be obtained by a known method. For example, an I ⁻ / I ₃ ⁻ based electrolyte can be obtained by mixing an ammonium salt of iodine and iodine.

As the second conductive layer (e), a conductive compound similar to that of the first conductive layer (b) can be used, but usually a metal such as platinum, silver, or gold is used.
As the second substrate (f), a glass plate, a polymer film or the like can be used as in the first substrate (a).

The dye-sensitized solar cell includes a first substrate (a), a first conductive layer (b), a metal oxide semiconductor layer (c) having a photosensitizer, an electrolyte layer (d), and a second substrate as described above. It can be produced by sequentially laminating the conductive layer (e) and the second substrate (f).
In the present invention, at least one of the first laminate (I) and the second laminate (II) should be transparent so that sunlight can reach the metal oxide semiconductor layer (c) having the photosensitizer. That's fine. The degree of transparency may be within a range where sunlight can be transmitted and the performance of the solar cell can be exhibited, but the visible light transmittance is desirably 70% or more.

In the present invention, a coating having a contact angle of 70 ° or less is provided on the outer surface of the first laminate (I) and / or the second laminate (II) having transparency. Thereby, even when contaminants such as dust in the atmosphere adhere, the contaminants can be effectively washed away by running water due to rainfall or the like.
As the film-forming composition for forming such a film, a composition containing an alkoxysilane compound is suitable, and the following two types can be particularly preferably used.
Composition 1: A film-forming composition comprising (h) an alkoxysilane compound, (i) a catalyst, (j) water, and (k) a solvent.
Composition 2: (p) Organic resin, (q) Composition for film formation containing alkoxysilane compound.

  Examples of the (h) alkoxysilane compound (hereinafter referred to as “(h) component”) in the composition 1 include, for example, tetramethoxysilane, tetraethoxysilane, tetra n-propoxysilane, tetraisopropoxysilane, tetra n-butoxysilane, Tetraalkoxysilanes such as tetraisobutoxysilane, tetrasec-butoxysilane, tetra-t-butoxysilane, tetraphenoxysilane, dimethoxydiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane , Phenyltrimethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, diphenyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimeth Xysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxy Examples include silane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, methyltrichlorosilane, and the like, and condensates thereof. Moreover, the alkoxysilane compound containing a carboxyl group, a hydroxyl group, a sulfone group, an oxyalkylene group etc. can also be used. Among these, as the component (h), tetraalkoxysilane is desirably included as an essential component. As tetraalkoxysilane, tetramethoxysilane and / or a condensate thereof are particularly suitable.

  (I) The catalyst (hereinafter referred to as “component (i)”) is a component that acts on the hydrolysis reaction of component (h). Specifically, for example, inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid; organic acids such as acetic acid, benzenesulfonic acid and toluenesulfonic acid; alkaline catalysts such as sodium hydroxide, potassium hydroxide, ammonia and amine compounds Organic organo compounds such as dibutyltin dilaurate, dibutyltin dioctate and dibutyltin diacetate; organoaluminum compounds such as aluminum tris (acetylacetonate) and aluminum monoacetylacetonate bis (ethylacetoacetate); titanium tetrakis (acetylacetonate) Organic zirconium compounds such as zirconium tetrakis (cetylacetonate); boron compounds such as boric acid, and the like.

The mixing amount of the component (i) is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the component (h) in terms of SiO ₂ . When the component (i) is less than 0.1 part by weight, the hydrophilicity of the formed film may not be sufficiently exhibited. If the amount exceeds 10 parts by weight, it is not possible to expect an effect corresponding to the mixing amount.

Here, SiO ₂ conversion is expressed in terms of the weight remaining as silica (SiO ₂ ) when a compound having a Si—O bond such as an alkoxysilane compound is completely hydrolyzed and then baked at 900 ° C. It is a thing.
In general, an alkoxysilane compound or the like reacts with water to cause a hydrolysis reaction to form silanol, and further has a property of causing a condensation reaction between silanols or between silanol and alkoxy. When this reaction is performed to the ultimate, silica (SiO ₂ ) is obtained. These reactions are RO (Si (OR) ₂ O) _n R + (n + 1) H ₂ O → nSiO ₂ + (2n + 2) ROH
(R represents an alkyl group. N is an integer.)
The amount of the remaining silica component is converted based on this reaction equation.

(J) The amount of water (hereinafter referred to as “component (j)”) is 100 to 50000 parts by weight, preferably 500 to 10,000 parts by weight, based on 100 parts by weight of the component (h) in terms of SiO _2. . With such a mixing amount, the condensation reaction of the silanol group of the (h) component generated from the reaction with the (j) component is suppressed, and the formed coating can exhibit sufficient hydrophilicity. When the mixing amount of the component (j) is less than 100 parts by weight, the hydrophilic expression effect in the formed film is lowered. Moreover, it becomes difficult to ensure the storage stability of the composition. When the amount is more than 50000 parts by weight, it is difficult to obtain a hydrophilic expression effect in the formed film.

(K) Examples of the solvent (hereinafter referred to as “(k) component”) include alcohols such as methanol, ethanol, n-propanol, and isopropanol, ethylene glycol, ethylene glycol monomethyl ether, propylene glycol, propylene glycol monomethyl ether, and diethylene glycol. In addition to glycol derivatives such as monoethyl ether and ethylene glycol monoethyl ether acetate, hydrocarbons, esters, ketones, ethers and the like can be mentioned. Among these, at least one selected from methanol, ethanol, isopropanol, propylene glycol monomethyl ether, and diethylene glycol monoethyl ether is preferably used from the viewpoints of hydrophilic expression and storage stability of the formed film.
The mixing amount of the component (k) is 100 to 50,000 parts by weight, desirably 500 to 10,000 parts by weight, with respect to 100 parts by weight of the component (h) in terms of SiO ₂ . When the amount is less than 100 parts by weight, it is difficult to uniformly dissolve the components (h), (i), and (j) described above. When the amount is more than 50000 parts by weight, it is difficult to obtain a hydrophilic expression effect in the formed film.

In composition 1, (l) a quaternary cation base-containing polymer (hereinafter referred to as “component (l)”) can also be mixed. By mixing the component (l), generation of repelling at the time of application is prevented, and a uniform film can be easily formed. Furthermore, the component (l) is also preferable from the viewpoint of the hydrophilicity of the formed film.
Examples of the quaternary cation base in the component (l) include quaternary ammonium bases, quaternary imidazolium bases, and quaternary phosphonium salts. Among these, a quaternary ammonium base is particularly preferable.

The component (l) can be obtained by using a quaternary cation base-containing monomer as a monomer component constituting the polymer. It can also be obtained by using a monomer capable of forming a quaternary cation base to obtain a polymer and then quaternizing it. Such a monomer is desirably contained in an amount of 3% by weight or more (preferably 15 to 80% by weight, more preferably 20 to 50% by weight) in the total monomer components constituting the component (l). If it is such a ratio, the more outstanding effect can be acquired in the point of repellency prevention property and hydrophilic property provision.
The mixing amount of the component (l) is usually 1 to 100 parts by weight, preferably 5 to 50 parts by weight in terms of solid content with respect to 100 parts by weight of the component (h) in terms of SiO ₂ .

In composition 1, it is preferable that (m) a metal oxide sol (hereinafter referred to as “(m) component”) having a particle diameter of 3 to 100 nm is further contained. By adding the component (m), the hydrophilicity of the formed film can be further increased.
Such component (m) is a colloidal solution in which colloidal particles made of a metal oxide are dispersed in a solvent. Examples of the metal component in the component (m) include silicon, aluminum, titanium, zirconium, antimony, and magnesium. Among these, silica sol in which the metal component is silicon is preferable.
The mixing amount of the component (m) is 5 to 1000 parts by weight, preferably 10 to 300 parts by weight in terms of solid content with respect to 100 parts by weight of the component (h) in terms of SiO ₂ .

  In the composition 1, in addition to the above-described components, for example, resins, thickeners, leveling agents, wetting agents, plasticizers, preservatives, antifungal agents, antialgae agents, antibacterial agents, surfactants, antifoaming agents UV absorbers, antioxidants, and the like can also be mixed.

The composition 2 is a composition containing (p) an organic resin (hereinafter referred to as “(p) component”) and (q) an alkoxysilane compound (hereinafter referred to as “(q) component”).
As the component (p), for example, an ethylene resin, a vinyl acetate resin, an alkyd resin, an acrylic resin, a urethane resin, an acrylic silicon resin, a fluorine resin, or a composite of these is used. Can do. Among these, acrylic resins, urethane resins, acrylic silicon resins, fluorine resins, and the like are preferable in terms of excellent weather resistance.

As the component (q) in the composition 2, the same component as the component (h) described above can be used, but from the viewpoint of compatibility with the component (p), early expression of surface hydrophilization, etc.
(Q-1) a condensate of alkoxysilane containing an alkoxyl group having 1 to 3 carbon atoms and an alkoxyl group having 4 to 12 carbon atoms (hereinafter referred to as “(q-1) component”), or
(Q-2) A condensate of an alkoxysilane containing a polyoxyalkylene group having 1 to 4 carbon atoms and an alkoxyl group having 1 to 4 carbon atoms (hereinafter referred to as “(q-2) component”). )
Is preferred.

In the (q-1) component, when the alkoxyl group contains one having 1 to 3 carbon atoms and 4 to 12 carbon atoms, compatibility with the (p) component is dramatically improved, and the surface A film having excellent orientation and various film properties can be formed. As the component (q-1), among the total alkoxyl groups, about 5 to 50 equivalent% of which is an alkoxyl group having 4 to 12 carbon atoms is compatible with the component (p) and the resistance of the coating. It is preferable because of excellent contamination. (Q-1) The average degree of condensation of a component is 4-20 normally.
Such a component (q-1) can be produced by a known method. For example, a tetraalkoxysilane condensate having an alkoxyl group having 1 to 3 carbon atoms is esterified with an alcohol having 4 to 12 carbon atoms. A method of denaturing by an exchange reaction is mentioned.

The (q-2) component can be suitably used particularly when the (p) component is a synthetic resin emulsion. Such a (q-2) component has good compatibility with the synthetic resin emulsion and can form a film excellent in stain resistance.
(Q-2) The carbon number of the alkoxyl group of a component is 1-4. When the number of carbons exceeds 4, the contamination resistance tends to decrease.
The average molecular weight of the polyoxyalkylene group is desirably 150 to 2,000. When the average molecular weight is less than 150, the compatibility with the component (p) decreases, and when it exceeds 2000, the water resistance, strength, etc. of the coating tend to decrease. Moreover, the average degree of condensation of (q-2) is usually 1-20.

  The component (q-2) can be produced by a known method. For example, one or two or more mixtures of alkoxysilane condensates are used as one or more polyoxyalkylene group-containing compounds. For example, a transesterification method using a coupling agent, and an addition reaction method using a coupling agent.

Such a component (q) is 1.0 to 50.0 parts by weight, preferably 2.0 to 30.0 parts by weight in terms of SiO _{2 with} respect to 100 parts by weight of the resin solid content of the component (p). It is desirable to blend. If the amount is less than 1.0 part by weight, the hydrophilicity of the coating is not sufficient, so that the stain resistance is poor. If the amount exceeds 50.0 parts by weight, the appearance of the cured coating tends to deteriorate or cracks are likely to occur.

  In composition 2, in addition to the above components, various additives such as thickeners, leveling agents, wetting agents, plasticizers, preservatives, antifungal agents, antialgae agents, antibacterial agents, surfactants, You may mix | blend a foaming agent, a ultraviolet absorber, antioxidant, a crosslinking agent, a catalyst, etc. suitably to such an extent that the effect of this invention is not impaired.

The dye-sensitized solar cell of the present invention is obtained by coating the film of the film forming composition as described above on the outside of the first laminate (I) and / or the second laminate (II). It is done. As long as a film is finally formed on the outer side of the first laminate (I) and / or the second laminate (II), the timing for applying the film-forming composition is not particularly limited. Or after assembly. If the transparency of the first laminate (I) and / or the second laminate (II) is not impaired, some treatment (primer treatment, degreasing treatment, etc.) can be performed before the coating composition is applied. .
When applying the film-forming composition, it is possible to employ a method such as spray, roller, brush, roll coater, flow coater, etc. in addition to a method of impregnating paper, cloth, nonwoven fabric, etc. and wiping. .
The film thickness to be formed is usually about 0.01 to 50 μm.

Examples and Comparative Examples are shown below to clarify the features of the present invention.
(Dye-sensitized solar cell production)
A solution obtained by mixing 1 part by weight of titanium alkoxide with 100 parts by weight of isopropyl alcohol was dropped into the same weight of water and stirred, and then the pH of the aqueous solution was adjusted to 2.0 using 1N nitric acid. A titanium hydroxide solution was prepared. A titanium oxide paste (anatase-type titanium oxide: titanium hydroxide = 97% by weight: 3% by weight) was prepared by mixing and stirring the anatase-type titanium oxide (primary particle diameter 10 nm) to this titanium hydroxide solution. .
The titanium oxide paste obtained by the above method is applied to a conductive polymer film (40 mm × 20 mm) by a squeegee method and dried at 50 ° C. for 3 hours to form a titanium oxide thin film having a thickness of 20 μm. After being immersed in an ethanol solution of (merocyanine) for 12 hours, the dye-adsorbed laminate was obtained by drying at 50 ° C. for 12 hours.
Next, this dye adsorbing laminate and a conductive polymer film on which platinum was vapor-deposited were bonded together so that the titanium oxide thin film and platinum face each other, thereby producing a solar battery cell. At this time, a double-sided tape having a thickness of 50 μm was used as a spacer. An electrolyte (0.5 M LiI + 0.05 M I ₂ / 3-methoxypropionitrile solution) was injected into the gap between the solar cells to obtain a dye-sensitized solar cell.

Example 1
200 parts by weight of acrylic silicon resin (solid content 50% by weight), 2 parts by weight of curing agent (dibutyltin laurate), silicate A (n-octyl alcohol modified product of methyl silicate condensate, transesterification rate 39 equivalent%, silica 45 parts by weight of the remaining amount ratio (33% by weight) was added and uniformly mixed by a conventional method to produce a film-forming composition A.
This film-forming composition A was applied to the outside of the dye-adsorbed laminate of the dye-sensitized solar cell by spraying so that the dry film thickness was about 15 μm, and dried at room temperature for 24 hours. When the contact angle with respect to the water on the surface of the coating was measured with a CA-A type contact angle measuring device, it was 34 °.
The solar cell obtained by the above method was irradiated with a 300 W halogen lamp from the dye adsorbing laminate side, and the open-circuit voltage at that time was measured using a tester. As a result, the open circuit voltage value was 480 mV.
Next, a contaminant (5 wt% carbon aqueous solution) was sprayed on the outside of the dye-adsorbed laminate of the dye-sensitized solar cell, dried at 50 ° C. for 1 hour, and then water was allowed to flow over the surface for 10 minutes. . After standing at room temperature for 15 hours, the halogen lamp was irradiated again, and the open circuit voltage value was measured.
By the above operation, the performance of the dye-sensitized solar cells before and after the pollutant spraying was compared. As a result, the open circuit voltage value after the pollutant spraying was about 99% before the pollutant spraying.

(Example 2)
To 200 parts by weight of an acrylic resin emulsion (solid content 50% by weight), add 24 parts by weight of silicate B (polyoxyethylene glycol # 200 modified product of ethyl silicate condensate, silica remaining ratio 21 wt%), and uniformly by a conventional method The composition B for film formation was manufactured by mixing.
This film-forming composition B was applied to the outside of the dye-adsorbed laminate of the dye-sensitized solar cell by spraying so that the dry film thickness was about 15 μm, and dried at room temperature for 24 hours. When the contact angle with respect to the water on the surface of the coating was measured with a CA-A type contact angle measuring device, it was 48 °.
About the solar cell obtained by the above method, the performance of the dye-sensitized solar cell before and after spraying contaminants was compared in the same manner as in Example 1. As a result, the open circuit voltage value after the pollutant spraying was about 97% before the pollutant spraying.

(Example 3)
100 parts by weight of tetramethoxysilane partially hydrolyzed condensate (average molecular weight 500, SiO ₂ ratio 51% by weight) in terms of SiO ₂ was prepared, and 0.5 parts by weight of aluminum tris (acetylacetonate) and ethanol were added thereto. 5400 parts by weight and 7500 parts by weight of water were mixed and stirred for about 30 minutes. Next, a quaternary cation base-containing acrylic polymer (quaternary cation base-containing monomer ratio 28 wt%, solid content 30 wt%) is mixed in an amount of 13 parts by weight in terms of solid content, and further silica sol (solid content 30 A film-forming composition C was produced by mixing 100% by weight in terms of solid content of 10% by weight, particle diameter of 10 to 20 nm, dispersion medium: isopropyl alcohol).
This film-forming composition C was applied to the outside of the dye-adsorbed laminate of the dye-sensitized solar cell by spraying so that the dry film thickness was about 1 μm, and dried at room temperature for 24 hours. When the contact angle with respect to the water on the surface of this coating was measured with a CA-A type contact angle measuring device, it was 23 °.
About the solar cell obtained by the above method, the performance of the dye-sensitized solar cell before and after spraying contaminants was compared in the same manner as in Example 1. As a result, the open circuit voltage value after the pollutant spraying was about 99% before the pollutant spraying.

(Comparative Example 1)
About the solar cell in which the film was not formed, the performance of the dye-sensitized solar cell before and after spraying the pollutant was compared in the same manner as in Example 1. As a result, the open circuit voltage value after the pollutant spraying was about 63% before the pollutant spraying.

(Comparative Example 2)
A film-forming composition D comprising an acrylic resin emulsion (solid content: 50% by weight) was applied to the outside of the dye-adsorbed laminate of the dye-sensitized solar cell by spraying so that the dry film thickness was about 15 μm. Dry at room temperature for 24 hours. When the contact angle with respect to the water on the surface of this coating was measured with a CA-A type contact angle measuring device, it was 80 °.
About the solar cell obtained by the above method, the performance of the dye-sensitized solar cell before and after spraying contaminants was compared in the same manner as in Example 1. As a result, the open circuit voltage value after the pollutant spraying was about 40% before the pollutant spraying.

It is the schematic which shows the dye-sensitized solar cell of this invention.

Explanation of symbols

1: Coating 2: Sun a: First substrate b: First conductive layer c: Metal oxide semiconductor layer with photosensitizer d: Electrolyte layer e: Second conductive layer f: Second substrate I: First stack body
II: Second laminate

Claims (2)

First substrate (a), first conductive layer (b), metal oxide semiconductor layer (c) having a photosensitizer, electrolyte layer (d), second conductive layer (e), second substrate (f) Are sequentially stacked, and a first stacked body (I) composed of the first substrate (a) to the first conductive layer (b), and a second stacked body (II) composed of the electrolyte layer (d) to the second substrate (f). ) Is a solar cell having transparency,
A film having a contact angle with water of 70 ° or less is formed on the outer surface of the first laminate (I) and / or the second laminate (II) ,
The film is formed by a film-forming composition containing (h) an alkoxysilane compound, (i) a catalyst, (j) water, (k) a solvent, and (l) a quaternary cation base-containing polymer . A dye-sensitized solar cell characterized by the above. The dye sensitizing method according to claim 1, wherein the coating film having a contact angle with water of 70 ° or less is further formed by a coating film forming composition further comprising (m) a metal oxide sol having a particle diameter of 3 to 100 nm. Sensitive solar cell.

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