JP4520142B2 - Dye-sensitized solar cell and dye-sensitized solar cell module - Google Patents

Description

  The present invention relates to a dye-sensitized solar cell and a dye-sensitized solar cell module. More specifically, the present invention relates to a dye-sensitized solar cell and a dye-sensitized solar cell module having a specific integrated structure.

  In recent years, solar cells that can convert sunlight into electric power have attracted attention as an energy source to replace fossil fuels.

  Currently, solar cells that are partly put into practical use include solar cells using crystalline silicon substrates and thin-film silicon solar cells. However, the former has a problem that the production cost of the silicon substrate is high. In the latter case, it is necessary to use various kinds of thin film silicon production gas and complicated apparatus, and also requires expensive glass with a transparent conductive film, resulting in high production costs and material costs.

  For this reason, in any solar cell, efforts have been made to reduce the cost per power generation output by increasing the efficiency of photoelectric conversion, but the above problem has not yet been fully solved.

  Japanese Patent No. 2664194 (Patent Document 1) proposes a wet solar cell applying photo-induced electron transfer of a metal complex as a new type of solar cell.

  This wet solar cell has a structure in which a photoelectric conversion layer is sandwiched between electrodes formed on two glass substrates (a glass with a transparent conductive film and a counter electrode) using an electrolyte material. ing.

  This photoelectric conversion material has an absorption spectrum in the visible light region by adsorbing a photosensitizing dye. In this solar cell, electrons are generated when the photoelectric conversion layer is irradiated with light, and the electrons move to the opposing electrode through an external electric circuit. The electrons that have moved to the electrode are carried by the ions in the electrolyte and return to the photoelectric conversion material side. In this way, electric energy can be taken out.

In addition, International Publication No. WO 97/16838 (Patent Document 2) proposes a dye-sensitized solar cell module in which a plurality of dye-sensitized solar cells are connected in series on the basis of this operation principle.
Specifically, each dye-sensitized solar cell has a structure in which a titanium oxide layer, an insulating porous layer, and a counter electrode are sequentially laminated on a glass substrate on which a transparent conductive film (electrode) patterned in a strip shape is formed. have. In addition, the dye-sensitized solar cells are connected in series by disposing the conductive layer of one dye-sensitized solar cell so that the counter electrode is in contact with the adjacent dye-sensitized solar cell.

Japanese Patent No. 2664194 International Publication No. WO97 / 16838 Pamphlet

  As described above, the basic structure of the dye-sensitized solar cell of Japanese Patent No. 2664194 is that a porous photoelectric conversion layer such as titanium oxide is formed on a glass with a transparent conductive film, and the porous photoelectric conversion layer is sensitized. A single cell was fabricated by holding a substrate on which a dye was adsorbed and a substrate on which another platinum film was formed on another glass with a transparent conductive film, and injecting an electrolyte between them. is there.

  Therefore, according to this technology, at least one glass with a transparent conductive film is used.

  In addition, the dye-sensitized solar cell module of WO97 / 16838 shown in FIG. 6 was produced by using a serial connection method adapted to an amorphous silicon solar cell module in the single cell structure of Japanese Patent No. 2664194. This is a dye-sensitized solar cell module. In FIG. 6, 61 is a transparent substrate, 62 is a transparent conductive film, 63 is a porous photoelectric conversion layer, 64 is a porous insulating layer, 65 is a conductive layer, 66 is an insulating layer, and 67 is an electrically insulating liquid sealing top cover. 68 and 69 denote terminals.

  Therefore, basically, this is a technique that uses a glass with a transparent conductive film, and further uses a laser scribing device to separate the transparent conductive film.

As described above, in any dye-sensitized solar cell, a glass with a transparent conductive film such as indium-tin composite oxide (hereinafter referred to as ITO) or tin oxide (SnO ₂ ) is used for the electrode on the light receiving surface side. I use it.

  However, this glass substrate with a transparent conductive film is expensive per se, and in addition, since mechanical devices (scribing lasers) for processing these are also expensive devices, a dye-sensitized solar using these The problem that the production cost of the battery is high has not been solved.

  As a result of earnest research to cope with the above-described problems, the present inventors have found that an expensive apparatus such as a laser scribe is formed without forming a transparent conductive film between the support and the porous photoelectric conversion layer. The present invention has been completed by finding a structure that does not use.

Thus, according to the present invention, a first conductive layer, a porous photoelectric conversion layer having a dye adsorbed thereon, a carrier transport layer, and a second conductive layer are sequentially provided between the first support and the second support. layer, as a carrier moving direction connecting the first conductive layer and the second conductive layer is parallel to the first support surface, have a disposed in parallel structure, and the said first conductive layer a A dye-sensitized solar cell is provided , wherein the two conductive layers have a structure arranged so as not to overlap in a direction perpendicular to the first support surface .
Furthermore, according to the present invention, there is provided a dye-sensitized solar cell, wherein the second conductive layer is composed of a current collector and a catalyst layer.

According to the present invention, there is also provided a dye-sensitized solar cell module in which a plurality of the dye-sensitized solar cells are arranged, wherein the first conductive layer of the dye-sensitized solar cell and another dye adjacent thereto A dye-sensitized solar cell module is provided in which dye-sensitized solar cells are integrated in series by contacting with the second conductive layer of the sensitized solar cell.
Furthermore, according to the present invention, there are a plurality of groups of the dye-sensitized solar cells connected in series, the first conductive layers at the ends of the adjacent dye-sensitized solar cells are in contact with each other, and adjacent to each other. A dye-sensitized solar cell module in which dye-sensitized solar cells are integrated in series-parallel connection by bringing the second conductive layers at the ends of the dye-sensitized solar cell group into contact with each other. Provided.

  Furthermore, according to the present invention, there is provided a dye-sensitized solar cell module in which a plurality of the dye-sensitized solar cells are arranged, the first conductive layers of adjacent dye-sensitized solar cells are brought into contact with each other, and A dye-sensitized solar cell module is provided, wherein the dye-sensitized solar cells are integrated in parallel by bringing the second conductive layers of adjacent dye-sensitized solar cells into contact with each other. .

  According to the present invention, a dye-sensitized solar cell and a dye-sensitized solar cell module can be manufactured at a lower cost than before.

  The dye-sensitized solar cell of the present invention (hereinafter simply referred to as a solar cell) includes a first conductive layer, a porous photoelectric conversion layer in which a dye is adsorbed, and carrier transport between a first support and a second support. The structure includes a layer and a second conductive layer sequentially. Furthermore, in the present invention, the first conductive layer, the porous photoelectric conversion layer, the carrier transport layer, and the second conductive layer have a carrier movement direction connecting the first conductive layer and the second conductive layer parallel to the first support surface (substantially). It is characterized by having a structure arranged in parallel so as to be parallel.

Hereinafter, the solar cell of this invention is demonstrated for every component.
The first support is a substrate that can functionally support the porous photoelectric conversion layer from the production stage to the product use stage, and is preferably made of a material having optical transparency and high heat resistance. It is. However, the first support may be any material as long as it substantially transmits at least light having a wavelength effective for the dye described below, and is not necessarily required to be transparent to all light. .

  Examples of the material of the first support include glass such as soda glass, fused silica glass, and crystal quartz glass, and heat resistant resin such as a flexible film or sheet.

  Moreover, it is preferable that a 1st support body is about 0.2-5 mm in thickness, and has heat resistance of 250 degreeC or more.

  Examples of the flexible film or sheet (hereinafter simply referred to as a film) include films of polyester, PET, polyacryl, polyimide, polytetrafluoroethylene, polyethylene, polypropylene, polystyrene, etc. Among these, long-term weather resistance It is preferable that the film has a property.

  Among them, the first support is preferably a polyimide film or a polytetrafluoroethylene film having heat resistance at this temperature because it may be heat-treated at a high temperature of about 200 ° C. when forming the conductive layer. .

  Furthermore, the first support can also be used when the completed solar cell is attached to another structure. For example, when using a support such as glass, the periphery of the support can be easily attached to another structure using metal-worked parts and screws.

  The second support is not particularly limited. Specifically, a support material similar to the first support material can be used, and if the second support is not subjected to a firing step, the second support has low heat resistance. May be. When the first support side is the light receiving surface of the solar cell, the second support may be opaque. In this case, in order to efficiently convert incident light, the second support is preferably made of a material that can reflect incident light, such as metal.

  Furthermore, in order to reduce the weight of the solar cell, it is desirable to use a film for the first support and / or the second support. From the viewpoint of maintaining and strengthening moisture resistance for extending the life of the solar cell. Therefore, for example, a laminated film of PET and aluminum is more preferable.

  When the first support and / or the second support is a film, the first conductive layer, the porous photoelectric conversion layer, the carrier transport layer, and the second conductive layer are opposed to each other by using a lamination method or the like. The first support and / or the second support can be brought into close contact with each other and sealed between the first support and the second support, and unnecessary voids can be reduced.

  The first conductive layer is formed on the first support so as to be at least partially in contact with the porous photoelectric conversion layer. In this case, a structure in which a part of the first conductive layer extends between the second support and the porous photoelectric conversion layer may be used. The second conductive layer is formed on the first support so as to be at least partially in contact with the carrier transport layer.

  As a material for forming the first conductive layer and the second conductive layer, for example, tin oxide doped with fluorine, ITO, boron, zinc oxide doped with gallium or aluminum, titanium oxide doped with niobium, etc. Examples thereof include conductive metal oxides, gold, silver, aluminum, indium, platinum, and carbon (carbon black, graphite, glass carbon, amorphous carbon, hard carbon, soft carbon, carbon whisker, carbon nanotube, and fullerene). These materials may be combined with one or more.

  The second conductive layer may be composed of a current collector and a catalyst layer. As a material for forming the current collector, one or a combination of two or more of the materials for forming the first conductive layer and the second conductive layer can be used.

Further, the material forming the catalyst layer is preferably platinum, carbon (carbon black, graphite, glass carbon, amorphous carbon, hard carbon, soft carbon, carbon whisker, carbon nanotube, fullerene), or a combination thereof. . Further, a conductive polymer material such as polyethylene dioxythiophene (PEDOT) may be selected as a material for forming the catalyst layer.
This catalyst layer is provided to promote the oxidation-reduction reaction.

Furthermore, the light transmittance of the first conductive layer and the second conductive layer is not particularly limited, and may be transparent or opaque.
The porous photoelectric conversion layer is composed of a semiconductor layer and a dye adsorbed thereto.

  Examples of the material constituting the semiconductor layer include known semiconductors such as titanium oxide, zinc oxide, tungsten oxide, barium titanate, strontium titanate, and cadmium sulfide. These materials may be combined with one or more. Of these, titanium oxide or zinc oxide is preferable in terms of conversion efficiency, stability, and safety.

  The average particle size of the semiconductor particles described above is, for example, a single or compound semiconductor particle having an average particle size of about 1 nm to 500 nm among those commercially available. The average particle diameter of the semiconductor particles used in the present invention is a value measured by SEM observation.

  As the porous photoelectric conversion layer, a layer in which a dye is adsorbed on a semiconductor layer in various forms such as a particle shape and a film shape can be used. Among these, in order to increase the conversion efficiency, it is desirable to have a film shape.

Various known methods can be used as a method for forming a film-like semiconductor layer on a substrate.
Specifically, a method of applying and baking a suspension containing semiconductor particles on a substrate such as screen printing, ink jet, or dispenser can be used. Among these, the screen printing method using the suspension of the semiconductor particles is preferable in order to increase the film thickness and reduce the manufacturing cost.

  The film thickness of the semiconductor layer is not particularly limited, but is preferably about 0.5 to 20 μm from the viewpoints of permeability, conversion efficiency, and the like.

Furthermore, in order to improve the conversion efficiency, it is necessary to adsorb more dye, which will be described later, to the semiconductor layer. Therefore, the film-like semiconductor layer preferably has a large specific surface area, specifically 10 m. a is preferably ² / ^{g~200m 2} / g approximately. In the present invention, the specific surface area means a value measured by the BET adsorption method.

  Examples of the solvent for suspending the semiconductor particles include glyme solvents such as ethylene glycol monomethyl ether, alcohol solvents such as isopropyl alcohol, mixed solvents such as isopropyl alcohol / toluene, water, and the like.

  The drying and baking of the semiconductor layer described above requires appropriate adjustment of temperature, time, atmosphere, and the like depending on the substrate used and the type of semiconductor particles.

For example, drying and baking can be performed for 10 seconds to 12 hours in the range of about 50 to 800 ° C. in the air or in an inert gas atmosphere.
This drying and baking may be performed once at a single temperature or twice or more by changing the temperature.

  As a dye that functions as a photosensitizer by adsorbing to the semiconductor layer, it absorbs visible light and / or infrared light in various regions, and in order to strongly adsorb the dye to the semiconductor layer, Those having an interlock group such as a carboxylic acid group, a carboxylic anhydride group, an alkoxy group, a hydroxyl group, a hydroxyalkyl group, a sulfonic acid group, an ester group, a mercapto group, and a phosphonyl group are preferred. Especially, what has a carboxylic acid group and a carboxylic anhydride group is more preferable.

  The interlock group has an electrical coupling function that facilitates electron transfer between the excited dye and the conduction band of the semiconductor layer.

  Examples of dyes containing these interlock groups include ruthenium metal complex dyes, azo dyes, quinone dyes, quinone imine dyes, quinacridone dyes, squarylium dyes, cyanine dyes, merocyanine dyes, and triphenylmethane dyes. Examples include dyes, xanthene dyes, porphyrin dyes, phthalocyanine dyes, berylene dyes, indigo dyes, naphthalocyanine dyes, and the like.

  Examples of the method for adsorbing the dye on the semiconductor layer include a method of immersing the semiconductor layer formed on the support in a solution in which the dye is dissolved (dye adsorption solution) for a necessary time.

  The solvent for dissolving the dye may be any solvent that dissolves the dye. For example, alcohols such as ethanol, ketones such as acetone, ethers such as diethyl ether and tetrahydrofuran, and nitrogen compounds such as acetonitrile. Halogenated aliphatic hydrocarbons such as chloroform, aliphatic hydrocarbons such as hexane, aromatic hydrocarbons such as benzene, esters such as ethyl acetate, water, and the like. These solvents can also be used as a mixture of two or more.

The concentration of the dye in the solution can be appropriately adjusted according to the type of the dye and the solvent to be used, but is preferably a high concentration in order to improve the adsorption function. For example, 5 × 10 ⁻ It is preferably ⁴ mol / liter or more.

  The carrier transport layer disposed between the porous photoelectric conversion layer and the second conductive layer is made of a conductive material that can transport electrons, holes, and ions.

  For example, hole transport materials such as polycarbazole, electron transport materials such as tetranitrofluororenone, conductive polymers such as polyroll, ionic conductors such as liquid electrolytes and polymer electrolytes, copper iodide, copper thiocyanate And p-type semiconductors.

  Among the conductive materials described above, an ionic conductor with high conductivity efficiency is preferable, and a liquid electrolyte including a redox electrolyte is particularly preferable.

  Such a redox electrolyte is not particularly limited as long as it can be generally used in a battery, a solar battery or the like.

Specifically, a combination of a metal iodide such as LiI, NaI, KI, and CaI ₂ and iodine and a combination of a metal bromide such as LiBr, NaBr, KBr, and CaBr ₂ and bromine are preferable. A combination of LiI and iodine having efficient electrolysis is preferable.

  Examples of the solvent used for this include carbonate compounds such as propylene carbonate, nitrile compounds such as acetonitrile, alcohols such as ethanol, water, aprotic polar substances, and the like. From this point of view, carbonate compounds and nitrile compounds are preferred. Two or more of these solvents can be mixed and used.

  The concentration of the redox electrolyte is in the range of 0.01 to 1.5 mol / liter, and among these, 0.01 to 0.7 mol / liter is preferable.

  Furthermore, according to this invention, the solar cell module which connected and integrated the said solar cell in series and / or in parallel is provided. The present invention can be applied to a solar cell module that requires a high voltage output by integrating the solar cells having the above-described configuration. Moreover, a see-through solar cell module can also be provided by using a member that transmits light of a desired wavelength as a member constituting the solar cell. Furthermore, solar cell modules that meet various purposes can be provided at low cost.

In particular,
(1) A solar cell module in which solar cells are integrated in series by bringing the first conductive layer of the solar cell into contact with the second conductive layer of another solar cell adjacent thereto,
(2) Having a plurality of groups of solar cells connected in series, contacting the first conductive layers at the ends of adjacent solar cell groups, and contacting the second conductive layers at the ends of adjacent solar cell groups A solar cell module in which dye-sensitized solar cells are integrated in series-parallel connection,
(3) The first conductive layers of adjacent solar cells are brought into contact with each other, and the second conductive layers of adjacent dye-sensitized solar cells are brought into contact with each other, so that the dye-sensitized solar cells are connected in parallel and integrated. The solar cell module made to do is mentioned.

  Here, in the case of (1), the current collector constituting the first conductive layer of the solar cell and the second conductive layer of another solar cell adjacent to the solar cell can be produced by the same material and / or the same process. preferable. According to this method, the first conductive layer and the current collector can be more easily produced.

  The solar cell and the solar cell module according to the present invention will be described more specifically with reference to the following embodiments, but the present invention is not limited to these embodiments.

(Embodiment Mode 1): Example of Manufacturing Solar Cell FIG. 1 shows an example of a schematic cross-sectional view of a solar cell.
In the figure, 1 is the first support, 2 is the first conductive layer, 3 is the porous photoelectric conversion layer, 4 is the carrier transport layer, 5 is the catalyst layer, 6 is the current collector (the catalyst layer and the current collector are combined) The second conductive layer 7) and 8 are second supports.

  The first support 1 is a glass substrate having a thickness of about 1 mm and having heat resistance of 450 ° C. or higher.

A titanium oxide (TiO ₂ ) powder, which is a metal oxide, is kneaded with a solvent and a binder to form a slurry or paste, and this is used to form a predetermined position on the first support 1 using a screen plate that is separately patterned. Was subjected to screen printing to form a precursor layer of a semiconductor layer. Thereafter, the precursor layer was leveled and then dried in an oven at 80 ° C.

  Specifically, a precursor layer was formed with a screen printing machine (LS-150 manufactured by Neurong Seimitsu Kogyo Co., Ltd.) using a titanium oxide paste produced by the following method.

  That is, as a method for producing titanium oxide particles, 125 ml of titanium isopropoxide (manufactured by Kishida Chemical Co., Ltd.) is dropped into 750 ml of a 0.1M nitric acid aqueous solution (manufactured by Kishida Chemical Co., Ltd.), hydrolyzed and heated at 80 ° C. for 8 hours. As a result, a sol solution was prepared.

Thereafter, the particles were grown at 230 ° C. for 11 hours in a titanium autoclave and subjected to ultrasonic dispersion for 30 minutes to prepare a colloidal solution containing titanium oxide particles having an average primary particle size of 15 nm. (Titanium oxide particles produced in this step are referred to as titanium oxide A.)
Further, the colloidal solution was gently concentrated with an evaporator until the titanium oxide concentration reached 15 wt%, and commercially available titanium oxide particles (titanium oxide B) (manufactured by Nippon Aerosil Co., Ltd., trade name P-25, anatase type) : Rutile type (7: 3) mixture, average primary particle size 20 nm) was added, ethanol twice that of the colloidal solution was added, and centrifugation was performed at 5000 rpm.

  After washing the titanium oxide particles produced in this step with ethanol, a solution prepared by dissolving ethyl cellulose (manufactured by Kishida Chemical Co., Ltd.) and terpineol (manufactured by Kishida Chemical Co., Ltd.) in absolute ethanol is added, and the titanium oxide particles are then stirred. Dispersed in the solution.

  Thereafter, ethanol was evaporated at a temperature of 50 ° C. under a vacuum of 40 mbar to prepare a titanium oxide paste.

  The final composition was adjusted so that the titanium oxide solid concentration was 20 wt%, ethyl cellulose 10 wt%, and terpineol 64 wt%.

Next, the precursor layer of the current collector 6 constituting the first conductive layer 2 and the second conductive layer is formed using an ITO paste in the same manner as the method for forming the precursor layer, and then air at 500 ° C. The current collector 6 constituting the semiconductor layer, the first conductive layer 2 and the second conductive layer 7 was sintered by firing in the medium.
Thereafter, the catalyst layer 5 constituting the second conductive layer 7 was obtained by forming a paste layer by screen printing using a carbon paste and drying the paste layer at about 100 ° C.

  The ITO paste used for forming the current collector 6 constituting the first conductive layer 2 and the second conductive layer 7 is an ITO paste manufactured by Sumitomo Osaka Cement Co., and the catalyst layer 5 constituting the second conductive layer 7. The carbon paste used was prepared by the following method.

Carbon paste was prepared by mixing carbon particles “Ketjen Black EC” (trade name) manufactured by Lion, ethyl cellulose as a binder, and n-methyl-2-pyrrolidone as a solvent. The weight mixing ratio was 40% carbon, 40% binder concentration, 20% solvent, and the dispersion time by the blender was 2 hours.
In addition to the above carbon particles, platinum or the like may be used.

  Furthermore, a conductive polymer material such as PEDOT may be used as the catalyst layer, and there is no problem even if it is a mixture thereof. Here, platinum or the like may be produced by a vapor phase method such as sputtering or vapor deposition.

  The thickness (X in FIG. 1) of each of the first conductive layer 2, the semiconductor layer, and the second conductive layer 7 is about 20 μm, and the width of each layer in the carrier transport direction (A, B, C, D in FIG. 1). , E) were 0.1 mm, 1.0 mm, 0.1 mm, 0.1 mm, and 0.1 mm, respectively.

  Since the carrier transport direction of the solar cell of the present invention is from A to E (or from E to A), there is a problem that the resistance increases when the width of each layer is extremely increased.

このルテニウム色素を、アセトニトリルとｎ−ブタノールエタノールを体積比１：１で混合した溶媒に、色素濃度４×１０^-4モル／リットルで溶解させて吸着用色素溶液とした。この吸着用色素溶液及び半製品（各部材が形成された第一支持体）を容器に入れ、約３０分間還流させることにより色素を半導体層に吸着させた。 Next, the semi-finished product thus obtained was immersed in a dye solution and refluxed for about 2 hours to adsorb the dye to the semiconductor layer, thereby obtaining a porous photoelectric conversion layer 3.
Specifically, a ruthenium dye (manufactured by Solaronix, trade name Ruthenium 535-bisTBA) having the following chemical structure (1) was used as the dye.

This ruthenium dye was dissolved in a solvent in which acetonitrile and n-butanol ethanol were mixed at a volume ratio of 1: 1 at a dye concentration of 4 × 10 ⁻⁴ mol / liter to obtain an adsorption dye solution. The dye solution for adsorption and the semi-finished product (first support on which each member was formed) were placed in a container and refluxed for about 30 minutes to adsorb the dye to the semiconductor layer.

Thereafter, the semi-finished product on which the dye was adsorbed was washed with absolute ethanol and dried at about 60 ° C. for about 20 minutes.
Thereafter, a precursor for forming a polymer electrolyte, which is the carrier transport layer 4, was injected into the whole.

  Subsequently, as a second support 8, a laminated film of PET-aluminum-PET is placed at a predetermined location, and a polymer electrolyte as the carrier transport layer 4 is formed by crosslinking polymerization at about 90 ° C. for 2 hours. To obtain a solar cell.

  The electrolytic solution in the polymer electrolyte is a mixed solvent of γ-butyrolactone (manufactured by Kishida Chemical Co., Ltd.) and ethylene carbonate (manufactured by Kishida Chemical Co., Ltd. (mixing ratio is γ-butyrolactone: ethylene carbonate = 7: 3 (volume ratio)). Then, dimethylpropylimidazolium iodide 0.6 mol / liter, lithium iodide 0.1 mol / liter, and iodine 0.1 mol / liter were dissolved.

  As the polymer material, compound A obtained by the following synthesis method 1 and diethyltoluenediamine (compound B) were used, and the mixing ratio thereof was compound A: compound B = 13: 1 (weight ratio).

(Synthesis method 1)
To 100 parts by weight of polytetramethylene glycol (trade name PTMG2000, manufactured by Mitsubishi Kasei Kogyo Co., Ltd.) in a reaction vessel, 18 parts by weight of tolylene diisocyanate and 0.05 parts by weight of dibutyltin dilaurate as a catalyst were added, at 80 ° C. Reaction was performed to prepare Compound A having a molecular weight of 2350.

Embodiment 2 Example of Manufacturing Solar Cell Module FIG. 2 shows an example of a schematic cross-sectional view of a solar cell module.
The solar cell module of FIG. 2 includes three unit cells sandwiched and integrated between a first support 201 and a second support 207.

  The first unit cell includes a first conductive layer 212, a porous photoelectric conversion layer 213, a carrier transport layer 214, and a catalyst layer 215 constituting a second conductive layer on the first support 201.

  The second unit cell includes a first conductive layer 222, a porous photoelectric conversion layer 223, a carrier transport layer 224, and a catalyst layer 225 constituting the second conductive layer on the first support 201.

  The third unit cell includes a first conductive layer 232, a porous photoelectric conversion layer 233, a carrier transport layer 234, a catalyst layer 235 constituting the second conductive layer, and a second conductive layer on the first support 201. It consists of a current collector 236.

  The current collector of the first unit cell is the same as the first conductive layer of the second unit cell, and the current collector of the second unit cell is the same as the first conductive layer of the third unit cell.

  The thickness and width of each layer of each unit cell may be equivalent to the shape described in the first embodiment.

  Generally, in order to calculate the photoelectric conversion efficiency of a solar cell module, the solar cell module area including the area of the electrode part is used. Therefore, the smaller the contact area (A and D and E in FIG. 1) of the first support of each of the first conductive layer and the second conductive layer is better.

  Although the thickness and width of each layer of each unit cell are limited by a film forming process such as a screen printing method or a vapor deposition method, an inexpensive manufacturing method is preferable in consideration of manufacturing costs.

  For example, when the screen printing method is used, although it depends on the viscosity coefficient of the material to be used, a film having a thickness of about 50 μm can be formed at a relatively low cost.

  Hereinafter, the solar cell and the solar cell module will be specifically described with reference to examples. However, the following examples are merely examples, and other methods known in the art can be employed in addition to this method. In the following examples and comparative examples, unless otherwise specified, solar cells and solar cell modules are manufactured using the conditions of the first and second embodiments.

Example 1
As a first support, 1 mm (4 B in FIG. 1) of titanium oxide paste (10 wt% of titanium oxide B added to titanium oxide A) on a 1 cm × 4 cm × 1 mm glass substrate by a screen printer. A paste layer for forming the porous photoelectric conversion layer 3 was formed so as to be × 3 cm and a film thickness of 15 μm. Thereafter, the paste layer was leveled and then dried at 80 ° C. for 30 minutes.

  Subsequently, the paste layer for forming the current collector 6 constituting the first conductive layer 2 and the second conductive layer using the ITO paste is changed to a width for forming the carrier transport layer (C in FIG. 1) of 0.1 mm. Thus, each was formed by screen printing so as to have a thickness of 0.1 mm (A, E in FIG. 1) × 3 cm and a film thickness of 15 μm, and dried at about 80 ° C. for 30 minutes.

  Thereafter, the paste layers are simultaneously fired in an oxygen atmosphere at about 500 ° C. for 1.5 hours, thereby forming the semiconductor layer for forming the porous photoelectric conversion layer 3, the first conductive layer 2, and the second conductive layer. Each current collector 6 was formed.

  Next, a carbon paste was applied by screen printing so that the catalyst layer 5 constituting the second conductive layer was 0.1 mm (D in FIG. 1) × 3 cm and the film thickness was 15 μm, and the coating was performed at about 100 ° C. for 30 minutes. Formed by drying.

  Next, after the dye is adsorbed on the semiconductor layer to form the porous photoelectric conversion layer 3, an electrolyte as the carrier transport layer 4 is formed between the porous photoelectric conversion layer 3 and the catalyst layer 5, and then PET -The solar cell was produced by arrange | positioning the 2nd support body 8 which has the laminated structure of aluminum-PET. This electrolyte is also impregnated in the porous photoelectric conversion layer.

As a result of measuring the operating characteristics of the solar cell produced in the above process under irradiation of pseudo sunlight of AM1.5, the short-circuit current density is 12.0 mA / cm ² , the open-circuit voltage value is 0.7 V, the FF is 0.65, and the conversion is performed. The efficiency was 5.5%.

(Example 2)
As a first support, on a glass substrate of 2.5 cm × 4 cm × 1 mm, a titanium oxide paste (a product obtained by adding 10 wt% of titanium oxide B to titanium oxide A) by a screen printing machine, 1 mm × 3 cm, film A paste layer for forming porous photoelectric conversion layers 213, 223, and 233 was formed so as to have a thickness of 15 μm. Then, after leveling each paste layer, it dried at 80 degreeC for 30 minutes.

  Next, a paste layer for forming a current collector 236 that constitutes the first conductive layers 212, 222, and 232 and the second conductive layer so that the ITO paste has a thickness of 0.1 mm × 3 cm and a film thickness of 15 μm by a screen printer. Formed. Then, after leveling each paste layer, it was dried at 80 ° C. for 30 minutes, and baked in an oxygen atmosphere at about 500 ° C. for 1.5 hours, whereby each of the semiconductor layers for forming each of the photoelectric conversion layers and each A conductive layer and a current collector 236 were formed.

  Next, a carbon paste is applied by screen printing so that the catalyst layers 215, 225, and 235 constituting the second conductive layer are 0.1 mm × 3 cm and the film thickness is 15 μm, and dried at about 100 ° C. for 30 minutes. Was formed.

  Next, after a dye is adsorbed to each semiconductor layer to form a porous photoelectric conversion layer, an electrolyte of each carrier transport layer 214, 224, 234 is formed between each porous photoelectric conversion layer and the catalyst layer. Then, the solar cell module was produced by arrange | positioning the 2nd support body 207 with a laminated structure of PET-aluminum-PET. This electrolyte is also impregnated in the porous photoelectric conversion layer.

As a result of measuring the operating characteristics of the solar cell produced by the above process under irradiation of artificial sunlight of AM1.5 as in Example 1, the short-circuit current density was 11.5 mA / cm ² , the open-circuit voltage value was 2.07 V, The FF was 0.63 and the conversion efficiency was 5.0%.

(Example 3)
It produced according to Example 2 except having used platinum for the catalyst layer which comprises the 2nd conductive layer. However, the method for forming the catalyst layer with platinum was based on the sputtering method. As a result of measuring the operating characteristics of the solar cell module produced by the above process under irradiation of artificial sunlight of AM1.5 as in Example 1, the short-circuit current density was 12.1 mA / cm ² , the open-circuit voltage value was 2.13 V, The FF was 0.64 and the conversion efficiency was 5.5%.

Example 4
It produced according to Example 2 except having used electroconductive polymer material PEDOT-OTs for the catalyst layer which comprises a 2nd electroconductive layer. PEDOT-OTs are prepared by mixing Baytron Baytron M-V2 and Bayer Baytron CB-40 in a volume of 1: 4, polymerizing at 100 ° C. for 1 hour, and then washing with p-toluenesulfonic acid. did. Moreover, the formation method of this catalyst layer was based on the doctor blade method.

As a result of measuring the operating characteristics of the solar cell module produced by the above steps under irradiation of pseudo sunlight of AM1.5 as in Example 1, the short-circuit current density was 9.9 mA / cm ² , the open-circuit voltage value was 2.01 V, The FF was 0.61 and the conversion efficiency was 4.0%.

(Example 5)
As shown in FIG. 3, a part of each of the first conductive layers 312, 322, and 332 is part of the second support 307 and each of the porous photoelectric conversion layers at the contact portion between the first conductive layer and the porous photoelectric conversion layer. It was fabricated according to Example 2 except that the structure extended between 313, 323, and 333 was adopted.

As a result of measuring the operating characteristics of the solar cell module produced by the above steps under irradiation of artificial sunlight of AM1.5 as in Example 1, a short-circuit current density of 12.6 mA / cm ² , an open-circuit voltage value of 2.1 V, The FF was 0.65 and the conversion efficiency was 5.7%.

(Example 6)
As shown in FIG. 4, it produced according to Example 2 except having connected the connection method of the adjacent solar cell in parallel. However, the catalyst layer and the current collector of the second conductive layer were formed by sputtering using only platinum. In addition, the external electrode of the module was taken out by connecting the first conductive layers 412, 422, and 442 and the second conductive layers 415 and 435 outside the module.

As a result of measuring the operating characteristics of the solar cell module produced by the above process under irradiation of pseudo sunlight of AM1.5 as in Example 1, the short-circuit current density was 12.0 mA / cm ² , the open-circuit voltage value was 0.69 V, The FF was 0.65 and the conversion efficiency was 5.4%.

(Example 7)
As shown in FIG. 5, it produced according to Example 2 and Example 6 except having connected the connection method of an adjacent solar cell in parallel. The catalyst layers 515, 525, and 545 constituting the second conductive layer were formed by sputtering using platinum.

As a result of measuring the operating characteristics of the solar cell module produced by the above steps under AM1.5 simulated sunlight irradiation as in Example 1, the short-circuit current density was 12.1 mA / cm ² , the open-circuit voltage value was 0.70 V, The FF was 0.66 and the conversion efficiency was 5.6%.

1 is a schematic cross-sectional view of a dye-sensitized solar cell of the present invention. It is a cross-sectional schematic diagram of the dye-sensitized solar cell module of the present invention. It is a cross-sectional schematic diagram of the dye-sensitized solar cell module of the present invention. It is a cross-sectional schematic diagram of the dye-sensitized solar cell module of the present invention. It is a cross-sectional schematic diagram of the dye-sensitized solar cell module of the present invention. It is a cross-sectional schematic diagram of a conventional dye-sensitized solar cell.

Explanation of symbols

1, 201, 301, 401, 501 First support 2, 212, 222, 232, 312, 322, 332, 412, 422, 442, 512, 522, 532, 542 First conductive layer 3, 63, 213, 223, 233, 313, 323, 333, 413, 423, 433, 443, 513, 523, 533, 543 Porous photoelectric conversion layer 4, 214, 224, 234, 314, 324, 334, 414, 424, 434, 444, 514, 524, 534, 544 Carrier transport layer 5, 215, 225, 235, 315, 325, 335, 415, 435, 515, 525, 545 Catalyst layer

6, 236, 336 Current collector 7 Second conductive layer 8, 207, 307, 407, 507 Second support 61 Transparent substrate 62 Transparent conductive film 64 Porous insulating layer 65 Conductive layer 66 Insulating layer 67 Electrical insulating liquid sealing Top cover 68, 69 terminal

Claims (9)

Between the first support and the second support, a first conductive layer, a porous photoelectric conversion layer in which a dye is adsorbed, a carrier transport layer, and a second conductive layer are sequentially provided, and the four layers are the first conductive layer. When such a carrier moving direction connecting the second conductive layer is parallel to the first support surface, have a disposed in parallel structure, and said first conductive layer and the second conductive layer, wherein A dye-sensitized solar cell having a structure arranged so as not to overlap in a direction perpendicular to a first support surface .   Between the first support and the second support, a first conductive layer, a porous photoelectric conversion layer in which a dye is adsorbed, a carrier transport layer, and a second conductive layer are sequentially provided, and the four layers are the first conductive layer. The second conductive layer is composed of a current collector and a catalyst layer, and the second conductive layer has a structure arranged in parallel so that the carrier moving direction connecting the first conductive layer and the second conductive layer is parallel to the first support surface. A dye-sensitized solar cell characterized by comprising:   The dye-sensitized solar cell according to claim 2, wherein the catalyst layer contains at least platinum, carbon, or a conductive polymer.   4. The dye-sensitized type according to claim 1, wherein a part of the first conductive layer extends between the second support and the porous photoelectric conversion layer. Solar cell. The dye-sensitized solar cell according to any one of claims 1 to 4 , wherein the first conductive layer and the second conductive layer are in contact with the first support and the second support, respectively. A dye-sensitized solar cell module in which a plurality of dye-sensitized solar cells according to any one of claims 1 to 5 are arranged, the first conductive layer of the dye-sensitized solar cell, and adjacent thereto A dye-sensitized solar cell module, wherein the dye-sensitized solar cells are integrated in series by contacting with a second conductive layer of another dye-sensitized solar cell. A dye-sensitized solar cell module in which a plurality of dye-sensitized solar cells according to any one of claims 1 to 5 are arranged, the first conductive layer of the dye-sensitized solar cell, and adjacent thereto The dye-sensitized solar cells are connected in series by contacting the second conductive layer of the other dye-sensitized solar cells, and there are a plurality of groups of the dye-sensitized solar cells connected in series, Dye sensitization by bringing the first conductive layers at the ends of adjacent dye-sensitized solar cell groups into contact with each other and the second conductive layers at the ends of adjacent dye-sensitized solar cell groups in contact with each other A dye-sensitized solar cell module, wherein solar cells are integrated in series-parallel connection. A dye-sensitized solar cell module in which a plurality of the dye-sensitized solar cells according to any one of claims 1 to 5 are arranged, wherein the first conductive layers of adjacent dye-sensitized solar cells are connected to each other. A dye-sensitized solar cell module, wherein the dye-sensitized solar cells are connected in parallel and integrated by bringing the second conductive layers of adjacent dye-sensitized solar cells into contact with each other. That the current collectors constituting the first conductive layer of the dye-sensitized solar cell and the second conductive layer of another dye-sensitized solar cell adjacent to the dye-sensitized solar cell are manufactured in the same material and / or in the same process. The dye-sensitized solar cell module according to any one of claims 6 to 8 .

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