JP2006310252A - Transparent electrode, dye-sensitized solar cell having it and dye-sensitized solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent electrode providing large energy conversion efficiency when used for a counter electrode of a dye-sensitized solar cell, to provide a dye-sensitized solar cell having translucency as a whole and having large energy conversion efficiency, and also to provide a dye-sensitized solar cell module. <P>SOLUTION: This transparent electrode contains transparent conductive metal oxide particles and catalyst particles containing a transition metal. This dye-sensitized solar cell 100 is provided with: a transparent substrate 1; transparent conductive films 2a and 2b formed on the transparent substrate 1; and a solar cell 40 formed on the transparent conductive films 2a and 2b. The sollar cell 40 is composed by stacking: a light reception electrode 3 containing a sensitizing dye and an oxide semiconductor and electrically connected to the transparent conductive film 2a; a separator 4; and a counter electrode 8 electrically connected to the transparent conductive film 2b, in this order. The counter electrode 8 has the transparent electrode. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a transparent electrode, and a dye-sensitized solar cell and a dye-sensitized solar cell module including the transparent electrode.

Conventionally, a dye-sensitized solar cell called a so-called facing type is known. And as this counter type dye-sensitized solar cell, two transparent substrates on which a transparent conductive film is formed are used, and a nano-sized particle size is transmitted on the transparent conductive film of one transparent substrate, and visible light is transmitted. A photoelectrode on which titanium oxide is formed is formed, and fine particles or thin films of platinum serving as a reduction catalyst for iodine (I ⁻ / I ₃ ⁻ ) as a redox pair are formed on the transparent conductive film of the other transparent substrate. By forming these two transparent substrates as a counter electrode so that the photoelectrode and the counter electrode face each other and enclosing an electrolyte containing iodine (I ⁻ / I ₃ ⁻ ) therebetween, What has translucency as a whole has been proposed (for example, Non-Patent Document 1). Such solar cells are expected to be applied to solar cells that can be installed on windows, solarium roofs, and the like by utilizing the translucency.

  On the other hand, a so-called three-layer dye-sensitized solar cell is known as a solar cell that can manufacture a solar cell module having a plurality of solar cells at a lower cost (for example, Non-Patent Document 2). FIG. 5 is a cross-sectional view showing a conventional three-layer dye-sensitized solar cell module. The three-layer dye-sensitized solar cell module 300 shown in FIG. 5 is divided into a plurality of film portions that are separated from each other via a groove 20 formed on one surface of the transparent substrate 1 by laser scribing or the like. A transparent conductive film 2 is formed.

  A plurality of solar cells 40 are provided on one surface of the transparent substrate 1. The solar cell 40 includes a light receiving electrode 3 electrically connected to one film portion of the transparent conductive film 2, a separator 4 made of an insulating porous body, and another film portion of the transparent conductive film 2. The counter electrode 8 which is electrically connected and is made of a carbon electrode has a three-layer structure in which layers are laminated by coating and sintering in this order. In the light receiving electrode 3, a sensitizing dye is adsorbed to a porous body made of titanium oxide. The porous body of each layer of the light receiving electrode 3, the separator 4 and the counter electrode 8 is impregnated with an electrolytic solution.

  The plurality of solar cells 40 are electrically connected in series with each other through the transparent conductive film 2. Furthermore, the surface opposite to the transparent substrate 1 of the dye-sensitized solar cell module 300 is laminated on one surface of the aluminum foil 30 with an adhesive film 15 made of a resin that can be bonded by heating, and the other surface is resin. The film 16 is sealed with a moisture-proof film laminated, and the adhesive film 15 flows so as to fill the space between the solar cells 40 by heat fusion, thereby sealing the solar cells 40.

The three-layer type dye-sensitized solar cell module having such a configuration can be obtained by using a single transparent substrate, and the solar cells can be formed by coating and sintering by printing or the like. Therefore, there is an advantage that even a large module can be manufactured at low cost.
Nikkei Electronics, 2003, 9-12, p. 37-74 Andreas Kay, Michael Gratzel, “Low Cost Photovoltaic Module Based on Die Sensitized Nanocrystalline Titanium Dioxide and Carbon Powder (Low cost photovoltaic modules based on dye sensitized nanocrystalline titanium and carbon powder ”, Solar Energy Materials and Solar Cells, Vol. 44, Elsevier Science, 1996, p.99-117

  In the case of the counter type dye-sensitized solar cell as described above, the voltage obtained from the solar cell as a structural unit having the light receiving electrode and the counter electrode is relatively low at about 0.8 V per cell. Therefore, in order to use as a large-sized solar cell module, it is necessary to connect a plurality of the structural units in series via an external circuit. In addition, the transparent substrate on which the transparent conductive film is formed is expensive, and the cost of this is large in the entire solar cell module. However, in the case of the opposed type, it is necessary to use at least two transparent substrates. Tend to be higher. Therefore, a translucent solar cell module that employs a counter-type dye-sensitized solar cell is difficult to suppress the manufacturing cost while ensuring practically sufficient energy conversion efficiency.

  On the other hand, in the case of a three-layer dye-sensitized solar cell, a carbon electrode that can be formed by coating and sintering and has relatively good reduction characteristics is widely used as the counter electrode. However, since this carbon electrode does not have transparency, the three-layer dye-sensitized solar cell can produce a large-sized solar cell module at a low cost as described above, but has sufficient energy conversion efficiency. While maintaining the above, it was not possible to achieve a translucent structure as a whole.

  Then, an object of this invention is to provide the transparent electrode which can obtain big energy conversion efficiency, when it is used for the counter electrode of a dye-sensitized solar cell. Another object of the present invention is to provide a dye-sensitized solar cell and a dye-sensitized solar cell module that are translucent as a whole and have high energy conversion efficiency.

  In order to solve the above problems, the transparent electrode of the present invention contains transparent conductive metal oxide particles and catalyst particles containing a transition metal.

  When the transparent electrode of the present invention is used as a counter electrode of a dye-sensitized solar cell by combining the transparent conductive metal oxide particles and the catalyst particles and forming an electrode so as to be transparent as a whole. In addition, it has become possible to obtain a large energy conversion efficiency. The effect of improving the energy conversion efficiency is considered to be manifested by the fact that the reaction rate of the reduction reaction on the surface of the transparent electrode of the oxidized form of the redox couple present in the electrolyte is greatly improved by the presence of the catalyst particles. As the ratio of the catalyst particles in the transparent electrode increases, it is expected that it becomes difficult to maintain the transparency of the entire electrode. However, the present inventors have shown that a large energy conversion efficiency can be obtained even when a transparent electrode contains catalyst particles in a proportion or form that can maintain transparency as a whole when used as a counter electrode. I found it.

The transparent conductive metal oxide particles include In ₂ O ₃ : Sn, SnO ₂ : F, SnO ₂ : Sb, ZnO: Al, ZnO: Ga, In ₂ O ₃ : Zn, TiO ₂ : Nb, and TiO _2. : It is preferable to contain at least one transparent conductive metal oxide selected from the group consisting of Ta. By using these transparent conductive metal oxides, the energy conversion efficiency can be particularly high. Furthermore, among these, TiO ₂ : Nb and / or TiO ₂ : Ta are more preferable from the viewpoint of improving chemical durability and conductivity. In the following description, TiO ₂ : Nb and TiO ₂ : Ta both refer to those having an anatase type crystal form.

  The dye-sensitized solar cell of the present invention includes a transparent substrate, a transparent conductive film formed on the transparent substrate, and a transparent conductive film formed on the transparent conductive film and containing a sensitizing dye and an oxide semiconductor. A photovoltaic cell in which a light receiving electrode electrically connected to the separator, a separator having an insulating porous body holding an electrolyte, and a counter electrode electrically connected to the transparent conductive film are laminated in this order; , And the counter electrode has the transparent electrode of the present invention.

  The dye-sensitized solar cell of the present invention has translucency as a whole and has high energy conversion efficiency by using the transparent electrode of the present invention as a counter electrode.

In the dye-sensitized solar cell, the transparent conductive film preferably contains TiO ₂ : Nb and / or TiO ₂ : Ta. Since TiO ₂ : Nb and TiO ₂ : Ta have high chemical durability and excellent conductivity, when the transparent conductive film contains TiO ₂ : Nb and / or TiO ₂ : Ta, high translucency is obtained as a whole. It is possible to achieve a dye-sensitized solar cell that has higher energy conversion efficiency and can maintain high energy conversion efficiency at a high level over a long period of time while ensuring. The crystal forms of TiO ₂ : Nb and TiO ₂ : Ta are both anatase types.

Further, when the transparent conductive film contains TiO ₂ : Nb and / or TiO ₂ : Ta, the energy conversion efficiency becomes higher in a dye-sensitized solar cell including such a transparent conductive film on the photoelectrode side. It can be considered that one of the reasons is that generation of leakage current can be suppressed. Note that the mechanism of leakage current generation is not necessarily clear, but is considered to depend on the compatibility between the crystal plane of the transparent conductive film in contact with the electrolyte and the electrolyte, and the types of elements contained in the transparent conductive film The leakage current is also reduced by selecting. TiO ₂ : Nb and / or TiO ₂ : Ta are considered to be excellent materials in terms of suppressing leakage current and obtaining high energy conversion efficiency.

  The electrolyte used in the dye-sensitized solar cell has a content of a solvent having a boiling point of 300 ° C. or less at 1 atm (hereinafter referred to as “low boiling point solvent”) based on the total mass of the electrolyte of 50 mass. % Or less. A dye-sensitized solar cell using an electrolyte having a low-boiling solvent content of 50% by mass or less is higher in temperature than a dye-sensitized solar cell using an electrolyte having a low-boiling solvent content exceeding 50% by mass. Therefore, even if it uses in a high temperature state, the fall of energy conversion efficiency can fully be suppressed. This is because when the content of the low boiling point solvent is 50% by mass or less, the solvent component can be sufficiently prevented from volatilizing from the electrolyte, and the alteration of the electrolyte is sufficiently prevented. In the present invention, the electrolyte refers to a substance that allows only ions to pass through without passing electrons, and examples of the electrolyte include liquid (electrolyte) and gel.

  The dye-sensitized solar cell module of the present invention includes a transparent substrate, a transparent conductive film formed on the transparent substrate, and a transparent conductive film formed on the transparent conductive film and containing a sensitizing dye and an oxide semiconductor. A plurality of solar cells in which a light-receiving electrode electrically connected to a film, a separator having an insulating porous body holding an electrolyte, and a counter electrode electrically connected to a transparent conductive film are laminated in this order A battery cell and a sealing layer sealing the plurality of solar cells, the counter electrode has the transparent electrode of the present invention, and the plurality of solar cells are electrically connected to each other through the transparent conductive film. Connected.

  This dye-sensitized solar cell module of the present invention has translucency as a whole and high energy conversion efficiency by using the transparent electrode of the present invention as a counter electrode. In addition, even large modules can be manufactured at low cost.

  A dye-sensitized solar cell module of the present invention includes a laminated sheet having a transparent inorganic material layer and a transparent support substrate laminated on both sides thereof, which are laminated on the surface of the sealing layer opposite to the transparent substrate. It is preferable. Thereby, deterioration by moisture absorption etc. of a photovoltaic cell can fully be prevented, maintaining the transparency as a whole.

  The transparent electrode of the present invention can be suitably used particularly for the counter electrode of a three-layer dye-sensitized solar cell, and a large energy conversion efficiency can be obtained. Moreover, the dye-sensitized solar cell and the dye-sensitized solar cell module of the present invention have translucency as a whole and have high energy conversion efficiency. Further, in the case of the dye-sensitized solar cell and the dye-sensitized solar cell module of the present invention, it is possible to generate power not only by the transparent substrate side (light receiving electrode side) but also by light received from the opposite surface. is there.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as the case may be. However, the present invention is not limited to the following embodiments. In addition, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a cross-sectional view showing an embodiment of a dye-sensitized solar cell according to the present invention. A dye-sensitized solar cell 100 shown in FIG. 1 is a transparent substrate 1 and is adjacent to the transparent substrate 1 on one side (lower side in the figure) of the transparent substrate 1 and is separated from each other through a groove 9. The transparent conductive film having the film portion 2a and the second film portion 2b, the light receiving electrode 3 provided on the surface of the first film portion 2a opposite to the transparent substrate 1, and the light receiving electrode 3 are disposed opposite to each other. The counter electrode 8 having an extending portion 8a extending in a direction substantially perpendicular to the transparent substrate 1 so as to be in contact with the second film portion 2b, and the first film portion sandwiched between the light receiving electrode 3 and the counter electrode 8 2a and a separator 4 formed so as to be sandwiched between the second film portion 2b. And the photovoltaic cell 40 which consists of the light-receiving electrode 3, the separator 4, and the counter electrode 8 is sealed with the sealing layer 5 provided so that the outer peripheral surface might be covered. Further, a transparent substrate 6 is provided on the surface of the counter electrode 8 opposite to the separator 4.

  In this dye-sensitized solar cell 100, when light incident from the surface F1 on the opposite side (upper side in the figure) of the transparent substrate 1 to the solar cell 40 reaches the light receiving electrode 3, the oxidation in the light receiving electrode 3 occurs. The sensitizing dye adsorbed on the physical semiconductor is excited, and electrons are injected from the sensitizing dye into the oxide semiconductor. Then, the electrons injected into the oxide semiconductor are collected in the first film portion 2a and taken out to the outside. The extracted electrons pass through a load connected to the outside, reach the counter electrode 8 through the second film portion 2b, and further reach the light receiving electrode 3 by the oxidation-reduction pair in the electrolytic solution held by the separator 4. Carried to reduce sensitizing dyes. By circulating the electrons in this way, the dye-sensitized solar cell 100 functions as a solar cell.

  The counter electrode 8 includes transparent conductive metal oxide particles and catalyst particles containing a transition metal, and is composed of a transparent electrode formed so as to be transparent as a whole. The counter electrode 8 is transparent to the extent that the opposite side can be visually recognized through the counter electrode 8 as long as the counter electrode 8 has transparency required for an application in which the dye-sensitized solar cell 100 is used.

As said transparent conductive metal oxide particle | grains, it is the particle | grains containing the transparent conductive metal oxide which can form a transparent conductive film, Comprising: When formed into a film independently, a transparent electrode can be formed. Those having transparency and conductivity as much as possible are used. The transparent conductive metal oxide particles include In ₂ O ₃ : Sn (ITO), SnO ₂ : F (FTO), SnO ₂ : Sb (ATO), ZnO: Al (AZO), ZnO: Ga (GZO), It is preferable to contain at least one transparent conductive metal oxide selected from the group consisting of In ₂ O ₃ : Zn (IZO), anatase TiO ₂ : Nb, and anatase TiO ₂ : Ta. Here, In ₂ O ₃ : Sn is a solid solution in which indium is substituted with tin oxide, and is also referred to as tin-doped indium oxide. Similarly, SnO ₂ : F is fluorine-doped tin oxide, SnO ₂ : Sb is antimony-doped tin oxide, ZnO: Al is aluminum-doped zinc oxide, ZnO: Ga is gallium-doped zinc oxide, In ₂ O ₃ : Zn is zinc-doped Indium oxide, TiO ₂ : Nb is also called niobium-doped titanium oxide, and TiO ₂ : Ta is also called tantalum-doped titanium oxide.

Of these, transparent electrically conductive metal oxide is _TiO 2: Nb and / or _TiO 2: preferably contains Ta. When the counter electrode 8 contains TiO ₂ : Nb and / or TiO ₂ : Ta as a transparent conductive metal oxide, TiO ₂ : Nb and TiO ₂ : Ta are In ₂ O ₃ : Sn, ZnO: Al, etc. Therefore, the durability of the counter electrode 8 and, in turn, the durability of the dye-sensitized solar cell 100 including the same are improved. Moreover, since TiO ₂ : Nb and TiO ₂ : Ta have superior conductivity compared to SnO ₂ : Sb and the like, the conversion efficiency of the dye-sensitized solar cell 100 is also improved. That is, when the transparent conductive metal oxide contains TiO ₂ : Nb and / or TiO ₂ : Ta, both high durability and high energy conversion efficiency can be achieved.

In the present specification, “the ratio (%) of the number of substituted solid solution atoms to the number of metal atoms of the metal oxide on the substitutional solid solution side” is defined as the doping rate of substituted solid solution atoms. Then, in the case of In ₂ O ₃ : Sn, the ratio of the number of Sn atoms to the number of In atoms contained in In ₂ O ₃ is the Sn doping rate.

_Here, In ₂ O 3: In Sn, it is preferable that the doping ratio of Sn is 1 to 25%. Similarly, in In ₂ O ₃ : Zn, the doping rate of Zn is 1 to 25%, in SnO ₂ : F, the doping rate of F is 5 to 50%, and in SnO ₂ : Sb, the doping rate of Sn 5-55% is, ZnO: in Al, the doping ratio of Al is _1~25%, ZnO: 1~25% doping ratio of Ga in the _Ga, in ₂ O 3: doping ratio of Zn in the Zn is In the case of 1 to 25%, TiO ₂ : Nb, the doping rate of Nb is preferably 0.5 to 20%, and in TiO ₂ : Ta, the doping rate of Ta is preferably 0.5 to 20%.

  In the transparent conductive metal oxide, when the doping rate is less than the lower limit, the electrical conductivity is reduced as compared with the case where the doping rate is equal to or higher than the lower limit. Tends to decrease. On the other hand, when the doping rate exceeds the upper limit, the light transmittance tends to be smaller than when the doping rate is equal to or lower than the upper limit.

  The transparent conductive metal oxide particles in the transparent electrode preferably have an average particle size of 5 to 150 nm. If the average particle size is less than 5 nm, the gap between the particles becomes narrow, so that the redox couple is difficult to diffuse in the transparent electrode, and the energy conversion efficiency tends to be lowered. On the other hand, when the average particle size exceeds 150 nm, the transparency tends to decrease due to light scattering. Here, the average particle diameter of the transparent conductive metal oxide particles is obtained by observing the thin piece of the transparent electrode with a transmission electron microscope and measuring the particle diameter (maximum inner diameter) of the transparent conductive metal oxide particles in the observation field. This is a value obtained as an average value.

  The catalyst particles are particles containing a transition metal as a single metal or as a metal compound having a transition metal. The catalyst particles are present in the transparent electrode together with the transparent conductive metal oxide particles in a mixing ratio, form and the like that are transparent as a whole. The catalyst particles preferably contain at least one transition metal selected from the group consisting of Pt, Co, Fe, Ni, and Mn.

Preferable specific examples of the catalyst particles include Pt particles containing (or consisting of) Pt metal, and Co, Fe such as La _0.7 Sr _0.3 Co _0.9 Fe _0.1 O _3. And composite oxide particles containing a composite oxide having a transition metal such as Ni and Mn. By using Pt particles or composite oxide particles as catalyst particles, particularly high energy conversion efficiency can be obtained while maintaining transparency.

  The average particle diameter of the catalyst particles is preferably 150 nm or less, and more preferably 50 nm or less. When the average particle diameter of the catalyst particles exceeds 150 nm, the reduction reaction rate of the redox couple tends to decrease. Therefore, in order to obtain a large energy conversion efficiency, it is necessary to increase the ratio of the catalyst particles. When the ratio is increased, the transparency of the electrode tends to decrease. Further, when the average particle size of the catalyst particles is increased, the transparency of the electrode tends to be lowered even if the mixing ratio is low. The average particle diameter of the catalyst particles is preferably 2 nm or more. The average particle diameter of the catalyst particles is a value obtained by a method using a transmission electron microscope, as described above for the average particle diameter of the transparent conductive metal oxide particles.

  The transparent electrode forming the counter electrode 8 preferably contains catalyst particles in a proportion of 0.01 to 10% by mass with respect to the amount of the transparent conductive metal oxide particles, 0.01 to 2 It is more preferable to contain in the ratio of the mass%. When the ratio of the catalyst particles is less than 0.01% by mass, the energy conversion efficiency tends to be lowered, and when it exceeds 10% by mass, the transparency tends to be lowered.

  The transparent electrode containing the transparent conductive metal oxide particles and the catalyst particles as described above is, for example, mixed with a dispersion obtained by dispersing the transparent conductive metal oxide particles and the catalyst particles in a solvent such as methanol. The solvent is removed from the mixed solution by heating to obtain a particle mixture in which catalyst particles are supported on transparent conductive metal particles, and a transparent electrode forming paste prepared by adding a thickener such as ethyl cellulose to the separator is used as a separator. It can be formed by applying to the surface of the film and heating to remove the solvent. The paste can be applied by a normal method such as a screen printing method. The dispersion liquid in which the transparent conductive metal oxide particles and the catalyst particles are dispersed can be prepared by a known method.

  The transparent substrate 1 should just be a translucent board | substrate formed with the material which permeate | transmits light, such as glass, a transparent plastic, an inorganic transparent crystal body. As the glass substrate, a frosted glass-like translucent substrate in which the reflection of light is reduced by appropriately roughening the surface thereof can also be used.

On one surface of the transparent substrate 1, a first film portion 2a and a second film portion 2b of the transparent conductive film are formed at positions separated from each other through a groove 9 where the transparent substrate 1 is exposed on the bottom surface. Has been. The first film portion 2a constitutes a so-called photoelectrode together with the light receiving electrode 3, and the second film portion 2b mediates electrical connection between the counter electrode 8 and an external circuit. This transparent conductive film is transparent such as In ₂ O ₃ : Sn, SnO ₂ : F, SnO ₂ : Sb, ZnO: Al, ZnO: Ga, In ₂ O ₃ : Zn, TiO ₂ : Nb, and TiO ₂ : Ta. It is suitably formed of a conductive metal oxide. Among these, TiO ₂ : Nb and TiO ₂ : Ta are preferable because they have high energy conversion efficiency and durability.

The light receiving electrode 3 contains a porous body made of oxide semiconductor particles and a sensitizing dye adsorbed thereto. The oxide semiconductor constituting the light-receiving electrode 3 is not particularly limited as long as it is a metal oxide that functions as a semiconductor. Preferred examples include TiO ₂ , ZnO, SnO ₂ , Nb ₂ O ₅ , _{In 2 O 3, WO 3,} ZrO 2, La 2 O 3, Ta 2 O 5, SrTiO 3, BaTiO 3 , and the like. Among these oxide semiconductors, anatase TiO ₂ is preferable.

  The sensitizing dye in the light-receiving electrode 3 is not particularly limited as long as it is a dye that is excited by light in the visible light region or infrared light region and emits electrons, but particularly has a wavelength of 200 to 10,000 nm. Those which are excited by the light and emit electrons are preferable. As such a sensitizing dye, a metal complex, an organic dye, or the like can be used. Examples of the metal complex include metal phthalocyanines such as copper phthalocyanine and titanyl phthalocyanine, chlorophyll or derivatives thereof, hemin, ruthenium, osmium, iron and zinc complexes (for example, cis-dicyanate-N, N′-bis (2,2′-bipyridyl). -4,4'-dicarboxylate) ruthenium (II)) and the like. As the organic dye, metal-free phthalocyanine, cyanine dye, merocyanine dye, xanthene dye, triphenylmethane dye, and the like can be used. In general, the light transmitted through the dye-sensitized solar cell 100 is colored in a color derived from the sensitizing dye.

  The light receiving electrode 3 is not particularly limited in terms of transparency as long as it has light transmittance in the visible light region or infrared light region that contributes to the emission of electrons of the sensitizing dye. It is preferable that the transparency is such that the opposite side can be visually recognized through the watermark, and the transparency required to be used in applications where the dye-sensitized solar cell 100 is used.

  The separator 4 is provided so as to fill the space between the opposing surfaces of the light receiving electrode 3 and the counter electrode 8, and also to fill the gap 9 between the side surface of the light receiving electrode 3 and the extension 8 a of the counter electrode 8.

  In the separator 4, a liquid or gel electrolyte is held in a transparent insulating porous body made of an insulating material. The electrolyte includes a redox pair dissolved in a solvent, and the transfer of electrons between the light receiving electrode 3 and the counter electrode 8 is mediated by the redox pair. Note that a part of the electrolyte normally penetrates into the light receiving electrode 3 and the counter electrode 8.

  The insulating porous body in the separator 4 is formed of particles such as glass beads and silicon dioxide (silica), for example. This insulating porous body is preferably one that can be formed by coating and sintering, and specifically, an insulating porous body obtained by sintering silica particles is preferable. The reason why a porous body obtained by sintering silica particles is preferable is that the porous body has good transparency because it has a low refractive index and low light scattering. The porous body preferably has an average particle size of 5 to 150 nm in order to ensure good transparency.

The solute of the electrolyte, a redox pair _I ³ - causing ^- / I ^- iodide dimethylpropyl imidazolium produce, lithium iodide, 1-methyl 3-propyl imidazolium, redox couple _Br ³ - / Br Examples thereof include lithium bromide, quinone that produces redox couple hydroquinone / quinone, and among these, solutes that produce I ₃ ⁻ / I ⁻ as the redox couple can be preferably used. The electrolyte may further contain, for example, 4-tert-butylpyridine as an additive for suppressing the transfer of electrons from the light receiving electrode 3 to the oxidant in the electrolyte.

  As the solvent in the electrolyte, an organic solvent or water can be used, but a solvent that is electrically inactive, has a high dielectric constant, and a low viscosity is preferable. Examples thereof include nitrile solvents such as methoxypropionitrile and acetonitrile, lactone solvents such as γ-butyrolactone and valerolactone, and carbonate solvents such as ethylene carbonate and propylene carbonate.

  Here, the content of the low-boiling solvent in the electrolyte can be 50% by mass or less based on the total mass of the electrolyte. Use of an electrolyte with a low-boiling solvent content of 50% by mass or less in the electrolyte improves durability at high temperatures, so even if it is used in a high temperature state, the decrease in energy conversion efficiency is sufficiently suppressed. it can. This is because when the content of the low boiling point solvent is 50% by mass or less, the solvent component can be sufficiently prevented from volatilizing from the electrolyte, and the alteration of the electrolyte is sufficiently prevented. As the solvent having a boiling point of more than 300 ° C. at 1 atm, an ionic liquid that takes a liquid state near room temperature can be used. Specifically, imidazolium salts such as 1-methyl 3-propylimidazolium iodide are used. Can be used.

  The seal layer 5 is provided mainly for the purpose of preventing the electrolyte held inside the solar battery cell 40 from leaking outside. The seal layer 5 can be formed of, for example, a thermoplastic resin, a heat crosslinkable resin, an epoxy adhesive, or the like. A similar sealing layer may be disposed between the counter electrode 8 and the transparent substrate 6 as necessary.

  The transparent substrate 6 is a transparent substrate similar to the transparent substrate 1 described above.

  The dye-sensitized solar cell 100 having the above configuration can be manufactured, for example, by the following method.

  First, a transparent conductive film is formed on one surface of the transparent substrate 1. The transparent conductive film is preferably formed using thin film manufacturing techniques such as spray coating, vacuum deposition, sputtering, CVD, and sol-gel. Then, a part of the transparent conductive film is removed by a method such as a laser scribing method to form a groove 9, and first and second film portions 2a and 2b that are separated from each other are formed.

  Subsequently, a dispersion in which oxide semiconductor particles having a predetermined particle size (preferably an average particle size of about 5 to 150 nm) are dispersed in a dispersion solvent is applied onto the first film portion 2a by a bar coater method, a printing method, or the like. After the application, the dispersion solvent is removed, and the oxide semiconductor particles are sintered by heating to form a porous body made of oxide semiconductor particles. The dispersion solvent used at this time may be any solvent that can disperse the oxide semiconductor particles, such as water, an organic solvent, or a mixed solvent thereof. Moreover, you may add surfactant, a viscosity modifier, etc. in a dispersion liquid as needed.

As another method for forming a porous body made of oxide semiconductor particles, a method of depositing an oxide semiconductor such as TiO _{2 in} the form of a film on the first film portion 2a may be employed. For example, a physical vapor deposition method such as electron beam vapor deposition, resistance heating vapor deposition, sputter vapor deposition, or cluster ion beam vapor deposition may be used, and the reaction product is made into a transparent conductive film by evaporating metal or the like in a reactive gas such as oxygen. A reactive vapor deposition method may be used. Alternatively, a chemical vapor deposition method such as CVD in which the flow of the reaction gas is controlled can be used.

  Next, the insulating porous body covering the surface opposite to the first film portion 2 a and one side surface of the porous body made of oxide semiconductor particles and filling the groove 9 is replaced with the insulating porous body of the separator 4. To form. This insulating porous body can be formed, for example, by applying a dispersion (slurry) in which silica particles are dispersed, drying and sintering the dispersion.

  Subsequently, the counter electrode 8 made of the transparent electrode of the present invention is electrically connected to the second film portion 2b on the surface of the insulating porous body opposite to the porous body made of oxide semiconductor particles. The extended portion 8a to be formed is formed. The transparent electrode can be formed by applying the transparent electrode forming paste described above on the porous body of the separator 4 and drying and sintering it. As conditions for drying and sintering in this case, for example, conditions similar to those generally used when forming a normal ITO transparent conductive film can be employed.

  A light-sensitive electrode 3 is formed by attaching a sensitizing dye (chemical adsorption, physical adsorption, deposition, etc.) to the formed porous body made of oxide semiconductor particles. The attachment can be performed by, for example, a method of immersing the porous body in a solution containing a dye. At this time, the adsorption and deposition of the sensitizing dye may be promoted by heating and refluxing the solution. A surface oxidation treatment for removing impurities mixed in the light receiving electrode 3 and inhibiting the photoelectric conversion reaction may be appropriately performed on the light receiving electrode 3.

  And the solar cell 40 comprised by the light-receiving electrode 3, the separator 4, and the counter electrode 8 is filled with electrolyte from the counter electrode 8 side, the seal layer 5 is formed, and the dye-sensitized solar cell 100 is obtained. Alternatively, the electrolyte may be impregnated after the seal layer 5 is formed.

  FIG. 2 is a cross-sectional view showing a dye-sensitized solar cell module according to the present invention. In the dye-sensitized solar cell module 200 shown in FIG. 2, the transparent conductive film 2 is formed on one surface of the transparent substrate 1. A groove 20 is formed in the transparent conductive film 2 by scribing with a laser or the like, and the transparent conductive film 2 has a plurality of film portions separated from each other through the groove 20. A plurality of solar cells 40 similar to the dye-sensitized solar cell 100 are provided on the transparent conductive film 2, and the plurality of solar cells 40 are electrically connected in series via the transparent conductive film 2. It is connected. In addition, the photovoltaic cell may be electrically connected in parallel through the transparent conductive film.

  In the solar battery cell 40, the light receiving electrode 3 is in contact with one film portion of the transparent conductive film 2, and the counter electrode 8 is in contact with the other film portion of the transparent conductive film 2, whereby the light receiving electrode 8 and The counter electrode 8 is electrically connected to each film portion.

  Further, the laminated sheet 10 in which the transparent inorganic material layer 12 is sandwiched between the two transparent support substrates 11a and 11b is opposite to the transparent substrate 1 with the seal layer 5 made of a resin that can be joined by heating. Laminated from the side.

A PET film or the like is used as the transparent support substrates 11a and 11b. The inorganic material layer 12 is formed of an inorganic material having transparency and moisture resistance. For example, an oxide such as silica (SiO ₂ ), alumina (Al ₂ O ₃ ), titania (TiO ₂ ), zirconia (ZnO ₂ ), and zinc oxide (ZnO) may be used alone or in combination on a transparent support substrate. A thin film is formed by vapor deposition, sputtering, or the like.

  The laminated sheet 10 is laminated, for example, by heating in a state where the laminated sheet 10 is bonded from the opposite side of the transparent substrate 1 with a resin film that can be bonded by heating interposed therebetween. Further, at this time, the resin film flows so as to cover the solar battery cell 40 and seals the resin cell 40, and is in close contact with the transparent conductive film 2 to form the seal layer 5. Examples of the resin used for forming the seal layer 5 include polyisobutylene.

  The dye-sensitized solar cell module 200 can be manufactured in the same manner as the dye-sensitized solar cell 100 except that a plurality of solar cells 40 are formed. Each layer can be formed in a lump using a printing method such as screen printing.

  Needless to say, the dye-sensitized solar cell module of the present invention is not limited to the above embodiment. For example, an antireflection layer or an ultraviolet cut layer may be provided on the surface of the transparent substrate 1 opposite to the transparent conductive film 2, or a layer having a desired function may be provided between the respective layers. .

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples.

Example 1
1 is a dye-sensitized solar cell having the same configuration as the dye-sensitized solar cell shown in FIG. 1 and having translucency, In ₂ O ₃ : Sn particles (Sn doping ratio: 17%, average particle size) A transparent electrode having a diameter of 50 nm) and Pt particles (average particle diameter of 10 nm) uniformly mixed with each other was prepared as a counter electrode.

A SnO ₂ : F transparent conductive film was formed on a glass substrate as a transparent substrate, and this was scribed with a YAG laser to divide the film into a first film portion and a second film portion. Then, a predetermined position on the first membrane portion, after forming TiO ₂ porous body (thickness 6 [mu] m) by sintering anatase TiO ₂ particles (average particle size 20 nm), the TiO ₂ On the porous body, a dispersion of silica particles (average particle diameter: 40 nm) was applied and sintered to form an insulating porous body.

Subsequently, a transparent electrode as a counter electrode was formed so as to cover the insulating porous body. In the formation of the transparent electrode, first, a dispersion obtained by dispersing In ₂ O ₃ : Sn particles and Pt particles in methanol, respectively, and the proportion of Pt particles is 0.1% by mass with respect to In ₂ O ₃ : Sn particles. Then, terpineol was added thereto, and then methanol was evaporated to prepare a particle mixture in which Pt particles were supported on In ₂ O ₃ : Sn particles. Then, a paste prepared by adding ethyl cellulose was applied to the separator by screen printing, heated at 150 ° C. for 10 minutes, dried, and then sintered by heating at 500 ° C. for 15 minutes. A counter electrode (thickness: 8 μm) was formed.

Next, Ruthenium 535bis-TBA (trade name (former name “N719”), manufactured by Sololonix), which is a sensitizing dye, was adsorbed on a porous body of TiO ₂ . Adsorption of the sensitizing dye was performed by leaving the whole in a 0.3 M ethanol solution of the sensitizing dye and allowing it to stand at room temperature for 48 hours.

  Further, a liquid electrolyte in which dimethylpropylimidazolium iodide (0.6M), iodine (0.1M), and 4-tert-butylpyridine (0.5M) are dissolved in γ-butyrolactone in the porous body of each layer. And a seal layer was formed of polyisobutylene to obtain a dye-sensitized solar cell. The content of γ-butyrolactone used as a solvent was 82% by mass based on the total mass of the electrolyte.

(Example 2)
As catalyst particles, La _0.7 Sr _0.3 Co _0.9 Fe _0.1 O ₃ particles (average particle size: 15 nm) were used instead of Pt particles, and the proportion of these particles was In ₂ O ₃ : Sn particles. A dye-sensitized solar cell was produced in the same manner as in Example 1 except that the paste was prepared at a ratio of 1.5% by mass.

(Comparative Example 1)
A dye-sensitized solar cell was produced in the same manner as in Example 1 except that a transparent electrode (thickness: 8 μm) composed only of In ₂ O ₃ : Sn particles was formed as a counter electrode.

  (Current-voltage characteristics of dye-sensitized solar cells)

About the dye-sensitized solar cell produced by said Example and comparative example, the xenon which let the AM filter (AM1.5) pass using a solar simulator (the product name "WXS-85-H type" by Wacom). The current-voltage characteristics were measured at room temperature using an IV tester while irradiating pseudo sunlight from a lamp light source (100 mW / cm ² ). FIG. 3 is a graph showing current-voltage characteristics of the dye-sensitized solar cell.

From the obtained current-voltage characteristics, the short circuit current density Jsc (mA · cm ⁻² ), the open circuit voltage Voc (V), and the shape factor F.I. F. Using these values, energy conversion efficiency η [%] was determined by the following formula (1) (Table 1). In the formula (1), _{P 0} represents the incident light intensity (mW / cm ^2).
η = 100 × (Voc × Jsc × FF) / P ₀ (1)

As shown in Table 1, the dye-sensitized solar cells of Examples 1 and 2 using the transparent electrode containing In ₂ O ₃ : Sn particles and Pt particles or transition metal composite oxide particles as a counter electrode, It was confirmed that the energy conversion efficiency was greatly improved as compared with Comparative Example 1 in which a transparent electrode containing no catalyst particles was used as a counter electrode.

(Example 3)
A dye-sensitized solar cell module having the same configuration as that shown in FIG. 2 was produced by the following procedure.

First, a transparent conductive film of SnO ₂ : F or In ₂ O ₃ : Sn (Sn doping ratio: 17%) is formed on a glass substrate, and this is scribed at a predetermined position and line width with a YAG laser, Divided into multiple membrane portions. And the paste which disperse | distributed the anatase type titanium oxide in the solvent was apply | coated to the predetermined position on each film | membrane part by screen printing, and it was made to dry, and the porous body of the titanium oxide for forming a light receiving electrode was formed. . Further, a paste in which glass beads or silica particles are dispersed is applied on the porous body by screen printing, and then dried by heating at 100 to 150 ° C. for 5 to 20 minutes, so that an insulating porous body as a separator Formed.

Subsequently, the surface of the separator opposite to the transparent substrate is covered, and the porous portion of titanium oxide and the side surface of the separator are extended substantially perpendicular to the transparent electrode to form an extended portion in contact with the adjacent film portion. As described above, a transparent electrode as a counter electrode was formed. In this case, In ₂ O ₃ : Sn particles (average particle size: 70 nm, particle size distribution: 20 to 150 nm) as transparent conductive metal oxide particles and Pt particles as catalyst particles are transparent in the ratio of catalyst particles. After applying a paste dispersed in a solvent at a ratio of 0.1% by mass with respect to the conductive metal oxide particles by screen printing, heating and drying at 100 to 150 ° C. for 5 to 20 minutes The whole was sintered by heating at 450 to 500 ° C. for 10 to 30 minutes to form a transparent electrode.

  Next, N719 as a sensitizing dye, an electrolytic solution in which dimethylpropylimidazolium iodide (0.6M), lithium iodide (0.1M), and 4-tert-butylpyridine are dissolved in γ-butyrolactone; Was mixed from the counter electrode side. By this impregnation, the sensitizing dye was adsorbed in the light receiving electrode. At this time, the electrolytic solution was captured not only between the particles in the porous body of each layer of the light receiving electrode, the separator and the counter electrode, but also in the fine pores on the surface of each particle.

Further, a laminated sheet having silica (SiO ₂ ) as a transparent inorganic material layer formed by vapor deposition and PET as two transparent support substrates provided on both sides of the laminated sheet is interposed through a thermoplastic resin sheet. Thus, several types of dye-sensitized solar cell modules in which a plurality of solar cells were connected in series inside were obtained from the counter electrode side by heat fusion.

Example 4
In ₂ O ₃ : Sn particles (Sn doping ratio: 17%, average particle size: 70 nm, particle size distribution: 20 to 150 nm) and Pt particles (average particle size: 10 nm, particle size distribution: 5 to 50 nm) are methanol, respectively. The dispersion was dispersed in a ratio such that the ratio of Pt particles was 0.01 to 10% by mass with respect to In ₂ O ₃ : Sn particles, and terpineol was added thereto, and then methanol was evaporated. Thus, a particle mixture in which Pt particles were supported on In ₂ O ₃ : Sn particles was prepared. And several types of dye-sensitized dyes having different average particle diameters of In ₂ O ₃ : Sn particles and Pt particles were obtained in the same manner as in Example 3 except that a counter electrode was formed using a paste dispersed in ethyl cellulose. A solar cell module was produced.

  It was confirmed that each of the obtained dye-sensitized solar cell modules has translucency and generates power with sunlight, as in the conventional one using a carbon electrode as a counter electrode. When the counter electrode (transparent electrode) was observed by TEM, the average particle size of Pt particles in the counter electrode was 5 to 50 nm, although the performance was particularly high in terms of energy conversion efficiency and the like.

  The dye-sensitized solar cell module produced in the same manner except that the average particle size of the Pt particles is 150 nm or more not only slightly decreases the solar cell performance such as energy conversion efficiency but also decreases the translucency. Tended to be.

(Example 5)
Preparation of Co particles (average particle size: 20 nm, particle size distribution: 10 to 80 nm) supported on In ₂ O ₃ : Sn particles (average particle size: 70 nm, particle size distribution: 20 to 150 nm) as catalyst particles Then, except that the counter electrode was formed by using a paste in which this was dispersed in ethyl cellulose, the same manner as in Example 3, several types of dye-sensitized dyes having different average particle diameters of Co particles and In ₂ O ₃ : Sn particles A solar cell module was produced.

  It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode. In the counter electrode, a part of Co was changed to cobalt oxide (CoO), but the deterioration of the function as a solar cell due to this was not particularly recognized.

(Example 6)
Pt particles (average particle size: 10 nm, particle size distribution: 5 to 50 nm) as catalyst particles are SnO ₂ : F particles (average particle size: 70 nm, particle size distribution: 20 to 150 nm) as transparent conductive metal oxide particles. The Pt particles and the SnO ₂ : F particles have different average particle diameters in the same manner as in Example 3, except that a support electrode is formed using a paste dispersed in ethyl cellulose. Several types of dye-sensitized solar cell modules were obtained. It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode.

(Example 7)
Pt particles (average particle size: 10 nm, particle size distribution: 5 to 50 nm) as catalyst particles were SnO ₂ : Sb particles (average particle size: 70 nm, particle size distribution: 20 to 20) as transparent conductive metal oxide particles. 150 nm) was prepared, and the counter electrode was formed using a paste dispersed in ethyl cellulose, and the average particle size of Pt particles and SnO ₂ : Sb particles was the same as in Example 3. Several different types of dye-sensitized solar cell modules were obtained. It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode.

(Example 8)
Pt particles (average particle size: 10 nm, particle size distribution: 5 to 50 nm) as catalyst particles and ZnO: Al particles (average particle size: 70 nm, particle size distribution: 20 to 150 nm) as transparent conductive metal oxide particles. In the same manner as in Example 3, several types having different average particle diameters of Pt particles and ZnO: Al particles were prepared in the same manner as in Example 3 except that a paste was dispersed in ethyl cellulose and a counter electrode was formed. The dye-sensitized solar cell module was obtained. It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode.

Example 9
Pt particles (average particle size: 10 nm, particle size distribution: 5 to 50 nm) as catalyst particles and ZnO: Ga particles (average particle size: 70 nm, particle size distribution: 20 to 150 nm) as transparent conductive metal oxide particles. In the same manner as in Example 3, except that a counter electrode was formed using a paste dispersed in ethyl cellulose, several types having different average particle diameters of Pt particles and ZnO: Ga particles were prepared. The dye-sensitized solar cell module was obtained. It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode.

(Example 10)
Pt particles (average particle size: 10 nm, particle size distribution: 5 to 50 nm) as catalyst particles, and In ₂ O ₃ : Zn particles (average particle size: 70 nm, particle size distribution) as transparent conductive metal oxide particles. 20 to 150 nm) was prepared, and a counter electrode was formed using a paste in which this was dispersed in ethyl cellulose, and in the same manner as in Example 3, Pt particles and In ₂ O ₃ : Zn particles Several types of dye-sensitized solar cell modules having different average particle diameters were obtained. It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode.

(Example 11)
As a laminated sheet, silica (SiO ₂ ), alumina (Al ₂ O ₃ ), titania (TiO ₂ ), zirconia (ZrO ₂ ) or zinc oxide (ZnO) is vapor-deposited on a PET (polyethylene terephthalate) film, and transparent Except for using a laminated sheet in which a thin film was formed as an inorganic material layer and a PET film was laminated on the thin film, several types of dye sensitization with different materials of the inorganic material layer in the laminated sheet were performed in the same manner as in Example 3. Type solar cell module was produced. It was confirmed that all of the obtained dye-sensitized solar cell modules had translucency and generated electricity by sunlight as in the conventional one using a carbon electrode as a counter electrode.

(Example 12)
In forming a transparent electrode as a counter electrode, SnO ₂ : Sb particles (average particle size 50 nm) are used instead of In ₂ O ₃ : Sn particles, and the ratio of Pt particles is based on SnO ₂ : Sb particles. A dye-sensitized solar cell was produced in the same manner as in Example 1 except that the paste was prepared at a ratio of 0.1% by mass.

(Example 13)
In forming a transparent electrode as a counter electrode, instead of using SnO ₂ : Sb particles, anatase-type TiO ₂ : Nb particles (average particle size 50 nm, Nb doping rate: 5.3%) were used. A dye-sensitized solar cell was produced in the same manner as in Example 1 except that the paste was prepared at a ratio of 0.1% by mass with respect to the TiO ₂ : Nb particles.

(Example 14)
In addition to forming a transparent conductive film of SnO ₂ : F on a glass substrate as a transparent substrate, a transparent conductive film of anatase type TiO ₂ : Nb (Nb doping rate: 5.3%) is formed Produced a dye-sensitized solar cell in the same manner as in Example 13.

(Example 15)
Instead of “Ruthenium 535 bis-TBA” as a sensitizing dye, “Ruthenium 520-DN” (trade name (former name “Z907”), manufactured by Sololonix) was used, and an electrolyte was used without using a low-boiling solvent. A dye-sensitized solar cell was produced in the same manner as in Example 13 except that an electrolyte containing no low-boiling solvent was used. In addition, the electrolyte which does not contain a low boiling point solvent was obtained by dissolving iodine (0.1 M) and 4-tert-butylpyridine (0.5 M) in 1-methyl 3-propylimidazolium iodide.

(Example 16)
In addition to forming a transparent conductive film of SnO ₂ : F on a glass substrate as a transparent substrate, a transparent conductive film of anatase type TiO ₂ : Nb (Nb doping rate: 5.3%) is formed Produced a dye-sensitized solar cell in the same manner as in Example 15.

(Comparative Example 2)
A dye-sensitized solar cell was produced in the same manner as in Example 16 except that a transparent electrode (thickness: 8 μm) consisting only of anatase TiO ₂ : Nb particles was formed as a counter electrode.

For the dye-sensitized solar cells produced in Examples 12 to 16, the short-circuit current density Jsc, the open-circuit voltage Voc, the shape factor F.I. F. And energy conversion efficiency (eta) [%] was calculated | required (Table 2).

As shown in Table 2, the dye-sensitized solar cells of Examples 13 and 14 in which the counter electrode metal oxide material is anatase type TiO ₂ : Nb are used, and the counter electrode metal oxide material is SnO ₂ : Sb. It was confirmed that the energy conversion efficiency was improved as compared with the dye-sensitized solar cell of Example 12. Further, when the results of Example 13 and Example 14 are compared, the dye-sensitized solar cell of Example 14 having a transparent conductive film made of anatase TiO ₂ : Nb is more transparent of SnO ₂ : F. It was confirmed that the energy conversion efficiency was improved as compared with the dye-sensitized solar cell of Example 13 provided with a conductive film.

Further, comparing the results of Example 15 and Example 16, the dye-sensitized solar cell of Example 16 having a transparent conductive film made of anatase-type TiO ₂ : Nb is more transparent of SnO ₂ : F. It was confirmed that the energy conversion efficiency was improved as compared with the dye-sensitized solar cell of Example 15 having a conductive film. As a result, when using an electrolyte that does not contain a low-boiling solvent, it was confirmed that the energy conversion efficiency of the dye-sensitized solar cell can be greatly improved by using a transparent conductive film made of anatase-type TiO ₂ : Nb. .

  Furthermore, the durability of the dye-sensitized solar cells of Examples 1, 12, and 13 was evaluated as follows. That is, the dye-sensitized solar cell was left in a dark place at a temperature of 85 ° C., and the energy conversion efficiency of each dye-sensitized solar cell was measured after a predetermined time. The results are shown in FIG.

As shown in FIG. 4, in the dye-sensitized solar cell of Example 13 in which the counter electrode metal oxide material is anatase TiO ₂ : Nb, the counter electrode metal oxide material is In ₂ O ₃ : F. Compared to the dye-sensitized solar cell of Example 1, it was confirmed that the decrease in energy conversion efficiency with time could be further suppressed. The dye-sensitized solar cell of Example 12 in which the counter electrode metal oxide material is SnO ₂ : Sb is the dye-sensitized solar cell of Example 13 in which the counter electrode metal oxide material is anatase TiO ₂ : Nb. Compared to the solar cell type, it was confirmed that although the initial conversion efficiency is low, the temporal deterioration of the energy conversion efficiency can be suppressed to the same extent as in Example 13.

(Example 17)
Pt particles (average particle size: 5-150 nm) as catalyst particles are anatase-type TiO ₂ : Nb particles (Nb doping ratio: 5.3%, average particle size: 5-150 nm) as transparent conductive metal oxide particles. The average particle size of Pt particles and anatase-type TiO ₂ : Nb particles was the same as in Example 3 except that a counter electrode was formed using a paste dispersed in ethyl cellulose. Several types of dye-sensitized solar cell modules with different diameters were obtained. It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode.

(Example 18)
Pt particles (average particle size: 5-150 nm) as catalyst particles are anatase-type TiO ₂ : Ta particles (Ta doping rate: 5.3%, average particle size: 5-150 nm) as transparent conductive metal oxide particles. The average particle size of Pt particles and anatase-type TiO ₂ : Ta particles was the same as in Example 3 except that a counter electrode was formed using a paste dispersed in ethyl cellulose. Several types of dye-sensitized solar cell modules with different diameters were obtained. It was confirmed that the obtained dye-sensitized solar cell module has translucency and generates power with sunlight in the same manner as a conventional one using a carbon electrode as a counter electrode.

It is sectional drawing which shows one Embodiment of the dye-sensitized solar cell by this invention. It is sectional drawing which shows one Embodiment of the dye-sensitized solar cell module by this invention. It is a graph which shows the current-voltage characteristic of a dye-sensitized solar cell. It is a graph which shows the time-dependent change of the conversion efficiency in the dye-sensitized solar cell which concerns on Example 1, 12, and 13. It is sectional drawing which shows the conventional dye-sensitized solar cell module.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Transparent substrate, 2 ... Transparent electrically conductive film, 2a ... 1st film | membrane part, 2b ... 2nd film | membrane part, 3 ... Light-receiving electrode, 4 ... Separator, 5 ... Sealing layer, 6 ... Transparent substrate, 8 ... Counter electrode ( Transparent electrode), 8a ... extension part, 10 ... laminated sheet, 11a, 11b ... transparent support substrate, 12 ... transparent inorganic material layer, 40 ... solar battery cell, 100 ... dye-sensitized solar cell, 200 ... dye increase Sensitive solar cell module.

Claims (8)

  A transparent electrode containing transparent conductive metal oxide particles and catalyst particles containing a transition metal. The transparent conductive metal oxide particles are In ₂ O ₃ : Sn, SnO ₂ : F, SnO ₂ : Sb, ZnO: Al, ZnO: Ga, In ₂ O ₃ : Zn, anatase TiO ₂ : Nb and anatase. The transparent electrode according to claim 1, comprising at least one transparent conductive metal oxide selected from the group consisting of type TiO ₂ : Ta. The transparent conductive metal oxide particles according to claim 1, wherein the transparent conductive metal oxide particles include at least one transparent conductive metal oxide selected from the group consisting of anatase TiO ₂ : Nb and anatase TiO ₂ : Ta. electrode. A transparent substrate;
A transparent conductive film formed on the transparent substrate;
A light-receiving electrode formed on the transparent conductive film and containing a sensitizing dye and an oxide semiconductor and electrically connected to the transparent conductive film, a separator having an insulating porous body holding an electrolyte, and A photovoltaic cell in which the counter electrode electrically connected to the transparent conductive film is laminated in this order;
With
The dye-sensitized solar cell in which the said counter electrode has the transparent electrode as described in any one of Claims 1-3. The dye-sensitized solar cell according to claim 4, wherein the transparent conductive film includes at least one selected from the group consisting of anatase TiO ₂ : Nb and anatase TiO ₂ : Ta.   The dye-sensitized solar cell according to claim 4 or 5, wherein the content of a solvent having a boiling point of 300 ° C or less at 1 atm contained in the electrolyte is 50% by mass or less based on the total mass of the electrolyte. A transparent substrate;
A transparent conductive film formed on the transparent substrate;
A light-receiving electrode formed on the transparent conductive film and containing a sensitizing dye and an oxide semiconductor and electrically connected to the transparent conductive film, a separator having an insulating porous body holding an electrolyte, and A plurality of solar cells in which counter electrodes electrically connected to the transparent conductive film are laminated in this order;
A sealing layer sealing the plurality of solar cells,
With
The counter electrode has the transparent electrode according to any one of claims 1 to 3,
The dye-sensitized solar cell module, wherein the plurality of solar cells are electrically connected to each other through the transparent conductive film.   The dye sensitizing type according to claim 7, comprising a laminated sheet having a transparent inorganic material layer and a transparent support substrate laminated on both sides thereof, which are laminated on a surface of the sealing layer opposite to the transparent substrate. Solar cell module.

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