JP2009087563A - Laminated body for oxide semiconductor electrode, oxide semiconductor electrode, dye-sensitized solar cell, manufacturing method for laminated body of oxide semiconductor electrode, and manufacturing method for oxide semiconductor electrode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated body for an oxide semiconductor electrode and an oxide semiconductor electrode with superior semiconductor characteristics capable of forming an electrode layer made of metal oxide by using a spray thermal decomposition method on a porous layer including metal oxide semiconductor fine particles without damaging semiconductor characteristics of the porous layer. <P>SOLUTION: In the laminated body for an oxide semiconductor electrode comprising a heat-resistant substrate, the porous layer formed on the heat-resistant substrate and including the metal oxide semiconductor fine particles, and a first electrode layer formed on the porous layer by using the spray thermal decomposition method and made of the metal oxide, the metal oxide semiconductor fine particles have their surface coated by an insulating material, and the problems can be solved by using the laminated body for an oxide semiconductor electrode. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention uses an oxide semiconductor electrode suitably used for a dye-sensitized solar cell and the like, a laminate for an oxide semiconductor electrode suitably used for producing the oxide semiconductor electrode, and an oxide semiconductor electrode The obtained dye-sensitized solar cell and the like.

In recent years, environmental problems such as global warming caused by an increase in carbon dioxide have become serious, and countermeasures are being promoted worldwide. In particular, active research and development on solar cells using solar energy as a clean energy source with a low environmental impact is underway. As such solar cells, single crystal silicon solar cells, polycrystalline silicon solar cells, amorphous silicon solar cells, compound semiconductor solar cells and the like have already been put into practical use, but these solar cells have high production costs, etc. There is a problem. Therefore, as a solar cell that has a small environmental load and can reduce the manufacturing cost, a dye-sensitized solar cell has attracted attention and research and development has been promoted.
In such a dye-sensitized solar cell, an oxide semiconductor electrode having a porous layer containing metal oxide semiconductor fine particles is used.

  An example of a general configuration of the dye-sensitized solar cell is shown in FIG. As illustrated in FIG. 8, a general dye-sensitized solar cell 100 includes a porous layer including metal oxide semiconductor fine particles carrying a first electrode layer 112 and a dye sensitizer on a base 111. An electrolyte layer 101 having a redox pair is a sealing material between the oxide semiconductor electrode 110 in which the layers 113 are stacked in this order and the counter electrode substrate 120 in which the second electrode layer 122 is formed on the counter substrate 121. 102 has a configuration formed inside 102. Then, the dye sensitizer adsorbed on the surface of the metal oxide semiconductor fine particles is excited by receiving sunlight from the substrate 111 side, and the excited electrons are conducted to the first electrode layer, and are then passed through the external circuit. Conducted to two electrode layers. Thereafter, electricity is generated by returning the electrons to the ground level of the dye sensitizer through the redox pair. A typical example of such a dye-sensitized solar cell is a Gretcher cell in which the porous layer is made of porous titanium dioxide and the content of the dye sensitizer is increased. It has been widely studied as a sensitized solar cell.

  In order to form a porous porous layer that is characteristic of the Gretchel cell, it is generally necessary to perform a baking treatment at 300 ° C. to 700 ° C. on the porous layer forming composition. Therefore, the base material cannot be used unless it is a heat-resistant material that can withstand the baking treatment, and a general polymer film cannot be used.

  In order to solve such problems, Patent Document 1 discloses that after a porous layer containing metal oxide semiconductor fine particles is formed on a heat-resistant substrate, an electrode layer made of a metal oxide is formed on the porous layer. Forming the oxide semiconductor electrode laminate, and then bonding the base material onto the electrode layer of the oxide semiconductor electrode laminate, and further peeling the heat-resistant substrate to form the oxide semiconductor electrode (Transfer method) is disclosed. According to such a transfer method, it is possible to form a porous layer on an arbitrary base material by transferring the porous layer fired on the heat-resistant substrate. Therefore, such a transfer method is useful in that an appropriate base material can be selected according to the use of the oxide semiconductor electrode.

  Here, in the above transfer method, an electrode layer made of a metal oxide is formed on the porous layer in the process of manufacturing the oxide semiconductor electrode laminate. As a method for forming the electrode layer, sputtering is performed. Generally, a method of forming a layer made of a metal oxide such as a vapor deposition method or a vapor deposition method is used. Among them, a spray pyrolysis method is known as a method capable of forming a dense electrode layer having excellent conductivity. The spray pyrolysis method comprises a metal oxide formed by spraying a metal compound solution containing a metal compound onto a heated porous layer to oxidize a metal contained in the metal compound on the porous layer. This is a method of forming an electrode layer. Such a spray pyrolysis method is attracting attention as a method capable of forming a denser and highly conductive electrode layer with high efficiency. A specific example of forming the electrode layer using a spray pyrolysis method is described in Patent Document 2, for example.

JP 2002-184475 A JP 2006-310256 A

By the way, as an oxide semiconductor electrode used for a dye-sensitized solar cell, one in which semiconductor fine particles made of a metal oxide of titanium oxide are usually used in the porous layer is used. When the electrode layer is formed on the porous layer containing the fine semiconductor particles by the above-described spray pyrolysis method, there is a problem that the porous layer is deteriorated.
That is, as described above, the spray pyrolysis method is a method of forming an electrode layer made of a metal oxide by spraying a metal compound solution containing a metal compound on the porous layer and oxidizing the metal contained in the metal compound. However, when the electrode layer is formed on the porous layer containing the metal oxide semiconductor fine particles by such a method, oxygen that oxidizes the metal contained in the metal compound is converted into the metal oxide in the porous layer. A phenomenon occurs in which the metal oxide semiconductor fine particles are reduced by being supplied from the semiconductor fine particles. For this reason, when the electrode layer is formed, the conductivity of the porous layer is lowered, and as a result, the semiconductor characteristics are impaired.

  The present invention has been made in view of such problems, and a metal is formed on a porous layer containing metal oxide semiconductor fine particles by a spray pyrolysis method without impairing the semiconductor characteristics of the porous layer. An object of the present invention is to provide an oxide semiconductor electrode laminate and an oxide semiconductor electrode that can form an oxide electrode layer and have excellent semiconductor characteristics.

  In order to solve the above problems, the present invention provides a heat-resistant substrate, a porous layer formed on the heat-resistant substrate and containing metal oxide semiconductor fine particles, and formed on the porous layer by a spray pyrolysis method. An oxide semiconductor electrode having a first electrode layer made of an oxide, wherein the metal oxide semiconductor fine particles are coated with an insulating material on the surface thereof A laminate is provided.

According to the present invention, in the step of producing the oxide semiconductor electrode laminate of the present invention, the metal oxide semiconductor fine particles contained in the porous layer are coated with an insulating material. Even when the first electrode layer is formed thereon by spray pyrolysis, the metal oxide semiconductor fine particles can be prevented from being reduced.
Further, according to the present invention, since the first electrode layer is formed by spray pyrolysis, the electron transfer performance with the porous layer is excellent.
For this reason, according to this invention, as a result that the electroconductivity of a porous layer decreases in a manufacture process, the laminated body for oxide semiconductor electrodes excellent in the semiconductor characteristic can be obtained.
Therefore, according to the present invention, an electrode layer made of a metal oxide is formed on a porous layer containing metal oxide semiconductor fine particles by a spray pyrolysis method without impairing the semiconductor characteristics of the porous layer. Therefore, it is possible to obtain a stacked body for an oxide semiconductor electrode that is excellent in semiconductor characteristics.

  In order to solve the above problems, the present invention provides a base material, a first electrode layer formed on the base material by a spray pyrolysis method, made of a metal oxide, and formed on the first electrode layer. An oxide semiconductor electrode comprising: a porous layer containing metal oxide semiconductor fine particles, wherein the metal oxide semiconductor fine particles have a surface coated with an insulating material I will provide a.

  According to the present invention, the metal oxide semiconductor fine particles contained in the porous layer are coated with an insulating material, and the first electrode layer is formed by spray pyrolysis, An oxide semiconductor electrode excellent in semiconductor characteristics can be obtained for the same reason as described above.

  As for the oxide semiconductor electrode of this invention, it is preferable that the contact bonding layer containing adhesive resin is formed between the said base material and the said 1st electrode layer. This is because by forming such an adhesive layer, the oxide semiconductor electrode of the present invention can be easily manufactured by the transfer method described above.

  Moreover, the present invention provides the above-described oxide semiconductor electrode according to the present invention, a counter substrate, and a counter electrode substrate having a second electrode layer formed on the counter substrate and made of a metal oxide. The porous layer and the second electrode layer are disposed so as to face each other, and an electrolyte layer including a redox pair is formed between the oxide semiconductor electrode and the counter electrode base material. A dye-sensitized solar cell is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the dye-sensitized solar cell excellent in power generation efficiency can be obtained by using the oxide semiconductor electrode which concerns on the said this invention excellent in the semiconductor characteristic.

  The present invention also provides a porous layer forming layer forming step of forming a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate using the heat resistant substrate, and the porous layer forming layer. A metal oxide semiconductor fine particle whose surface is coated with an insulating material on the heat-resistant substrate. A porous layer forming step for forming a porous layer; and a first electrode layer forming step for forming a first electrode layer made of a metal oxide on the porous layer by spray pyrolysis. The manufacturing method of the laminated body for oxide semiconductor electrodes characterized by these is provided.

According to the present invention, the porous layer forming step includes the porous layer forming layer forming step and the insulating coating step, and includes a metal oxide semiconductor fine particle whose surface is coated with an insulating material. By forming the porous layer, the metal oxide semiconductor fine particles contained in the porous layer are reduced when the first electrode layer is formed by spray pyrolysis in the first electrode layer forming step. Can be prevented.
Further, according to the present invention, the first electrode layer forming step forms the first electrode layer by spray pyrolysis, so that the electron transfer performance with the porous layer is dense and dense. The 1st electrode layer excellent in can be formed.
For this reason, according to the present invention, it is possible to manufacture a laminated body for an oxide semiconductor electrode having excellent semiconductor characteristics.

  Furthermore, the present invention provides a porous layer forming layer forming step of forming a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate using the heat resistant substrate, and the porous layer forming layer. A metal oxide semiconductor fine particle whose surface is coated with an insulating material on the heat-resistant substrate. A porous layer forming step of forming a porous layer; a first electrode layer forming step of forming a first electrode layer made of a metal oxide on the porous layer by spray pyrolysis; and the first A method for producing an oxide semiconductor electrode, comprising: a base material adhesion step for adhering a base material on an electrode layer; and a heat resistance substrate peeling step for peeling the heat resistant substrate from the porous layer. provide.

  According to the present invention, the porous layer forming step includes the porous layer forming layer forming step and the insulating coating step, and includes a metal oxide semiconductor fine particle whose surface is coated with an insulating material. An oxide having excellent semiconductor characteristics for the same reason as described above, because the first electrode layer forming step is to form the first electrode layer by spray pyrolysis. A semiconductor electrode can be manufactured.

  The laminate for an oxide semiconductor electrode and the oxide semiconductor electrode according to the present invention are formed on a porous layer containing metal oxide semiconductor fine particles by metal spray oxidation without damaging the semiconductor characteristics of the porous layer. It is possible to form an electrode layer made of a material, and there is an effect that the semiconductor characteristics are excellent.

The present invention relates to a laminate for an oxide semiconductor electrode, an oxide semiconductor electrode, a dye-sensitized solar cell using the same, a method for producing a laminate for an oxide semiconductor electrode, and a method for producing an oxide semiconductor electrode. It is.
Hereinafter, these will be described in order.

A. First, the laminated body for oxide semiconductor electrodes of this invention is demonstrated. The oxide semiconductor electrode western laminate of the present invention is formed on a heat resistant substrate, a porous layer formed on the heat resistant substrate and containing metal oxide semiconductor fine particles, and a spray pyrolysis method on the porous layer, A first electrode layer made of a metal oxide, wherein the surface of the metal oxide semiconductor fine particles is covered with an insulating material.

Such a laminated body for oxide semiconductor electrodes of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the oxide semiconductor electrode laminate of the present invention. As illustrated in FIG. 1, an oxide semiconductor electrode laminate 10 of the present invention includes a heat resistant substrate 1, a porous layer 2 formed on the heat resistant substrate 1 and containing metal oxide semiconductor fine particles, and the porous A first electrode layer 3 made of a metal oxide and having a surface covered with an insulating material of the metal oxide semiconductor fine particles contained in the porous layer 2. It is characterized by being.
The first electrode layer 3 in the present invention is formed on the porous layer 2 by spray pyrolysis.

  Here, as described above, the spray pyrolysis method is performed by spraying a metal compound solution containing a metal compound on a heated porous layer and oxidizing the metal contained in the metal compound on the porous layer. This is a method of forming a first electrode layer made of a metal oxide.

According to the present invention, in the step of producing the oxide semiconductor electrode laminate of the present invention, the metal oxide semiconductor fine particles contained in the porous layer are coated with an insulating material. Moreover, even when the first electrode layer is formed by spray pyrolysis, the metal oxide semiconductor fine particles can be prevented from being reduced.
That is, as described above, the spray pyrolysis method is a method of forming an electrode layer made of a metal oxide by spraying a metal compound solution containing a metal compound on the porous layer and oxidizing the metal contained in the metal compound. The metal oxide semiconductor fine particles contained in the porous layer when the first electrode layer is formed are useful as a method for forming a dense electrode layer having excellent electron transfer performance with the porous layer. There was a problem that the phenomenon of reduction occurred and the porous layer deteriorated. In this regard, according to the present invention, when the metal compound is oxidized in the spray pyrolysis method by using the metal oxide semiconductor fine particles whose surface is coated with an insulating material, the metal oxide semiconductor fine particles are used. It is possible to prevent oxygen from being supplied from the semiconductor fine particles.
In the oxide semiconductor electrode laminate according to the present invention, since the first electrode layer is formed by the spray pyrolysis method described above, the electron transfer performance with the porous layer is excellent. . For this reason, according to this invention, as a result that the electroconductivity of a porous layer decreases in a manufacture process, the laminated body for oxide semiconductor electrodes excellent in the semiconductor characteristic can be obtained.
Therefore, according to the present invention, an electrode layer made of a metal oxide is formed on a porous layer containing metal oxide semiconductor fine particles by a spray pyrolysis method without impairing the semiconductor characteristics of the porous layer. Therefore, it is possible to obtain a stacked body for an oxide semiconductor electrode that is excellent in semiconductor characteristics.

  In addition, the laminated body for oxide semiconductor electrodes of this invention is used suitably in order to produce the oxide semiconductor electrode mentioned later.

The oxide semiconductor electrode of the present invention has at least a heat-resistant substrate, a porous layer, and a first electrode layer, and may have any other configuration as necessary.
Hereafter, each structure used for the oxide semiconductor electrode of this invention is demonstrated in order.

1. Porous layer First, the porous layer used in the present invention will be described. The porous layer used in the present invention has a property of imparting semiconductor characteristics to an oxide semiconductor electrode produced using the oxide semiconductor electrode laminate of the present invention. The porous layer used in the present invention is characterized by containing metal oxide semiconductor fine particles whose surface is coated with an insulating material.
Hereinafter, such a porous layer will be described in detail.

(1) Metal oxide semiconductor fine particles First, the metal oxide semiconductor fine particles used in the present invention will be described. As described above, the metal oxide semiconductor fine particles used in the present invention are characterized in that the surface is coated with an insulating material.

The metal oxide semiconductor fine particles used in the present invention are not particularly limited as long as they are made of a metal oxide material having semiconductor characteristics. Depending on the use of the oxide semiconductor electrode laminate of the present invention, etc. Can be appropriately selected and used. Examples of the metal oxide material constituting the metal oxide semiconductor fine particles used in the present invention include TiO ₂ , ZnO, SnO ₂ , ITO, ZrO ₂ , MgO, Al ₂ O ₃ , CeO ₂ , Bi ₂ O ₃ , _{Mn 3 O 4, Y 2 O} 3, WO 3, Ta 2 O 5, Nb 2 O 5, La 2 O 3 and the like. The metal oxide semiconductor fine particles made of these metal oxide materials are suitable for forming a porous porous layer, and can improve energy conversion efficiency and reduce costs, and thus are suitable for the present invention. Used.

The metal oxide semiconductor fine particles used in the present invention may be all made of the same metal oxide material, or two or more types made of different metal oxide materials may be used. In addition, the metal oxide semiconductor fine particles used in the present invention may have a core-shell structure in which one type is a core fine particle and the other metal oxide semiconductor fine particles include the core fine particle to form a shell.
In particular, in the present invention, it is most preferable to use TiO ₂ as the semiconductor oxide fine particles. This is because TiO ₂ is particularly excellent in semiconductor characteristics.

  The particle size of the metal oxide semiconductor fine particles used in the present invention is not particularly limited as long as the surface area of the porous layer can be within a desired range, but is usually within the range of 1 nm to 10 μm. It is preferable that it is in the range of 10 nm-1000 nm especially. If the particle size is smaller than the above range, the respective metal oxide semiconductor fine particles may aggregate to form secondary particles, and if the particle size is larger than the above range, the porous layer becomes thicker. This is because the porosity of the porous layer, that is, the specific surface area may decrease. Here, when the surface area of the porous layer is reduced, for example, when a dye-sensitized solar cell is produced using the oxide semiconductor electrode laminate of the present invention, a dye sufficient for photoelectric conversion is used. It may be difficult to support the sensitizer on the porous layer.

  In the present invention, all the metal oxide semiconductor fine particles may have the same particle diameter, or two or more kinds of metal oxide semiconductor fine particles having different particle diameters may be used. Since the light scattering effect in the porous layer can be enhanced by using the metal oxide semiconductor particles having different particle diameters in combination, for example, a dye-sensitized solar cell using the oxide semiconductor electrode laminate of the present invention Is advantageous in that light absorption by the dye sensitizer can be efficiently performed.

  In the present invention, when two or more kinds of metal oxide semiconductor fine particles having different particle diameters are used, examples of the combination of different particle diameters include, for example, metal oxide semiconductor fine particles in a range of 10 to 50 nm and a range of 50 to 800 nm. The combination with the metal oxide semiconductor fine particle in the inside can be illustrated.

  The metal oxide semiconductor fine particles used in the present invention are those whose surfaces are coated with an insulating material, but the insulating materials used in the present invention are those when the surface of the metal oxide semiconductor fine particles is coated. When the first electrode layer is formed on the porous layer by the spray pyrolysis method, it is particularly limited as long as the metal oxide material constituting the metal oxide semiconductor fine particles has an insulating property that can be reduced. Usually, a metal oxide is used although it is not. This is because the metal oxide is not only excellent in insulation, but also excellent in film formability because it can be formed into the pores only by immersing the porous layer in the solution.

Examples of the metal oxide used as the insulating material in the present invention include aluminum oxide (Al ₂ O ₃ ), magnesium oxide (MgO), tin oxide (SnO ₂ ), calcium oxide (CaO), and tungsten oxide (WO ₃ ), indium oxide (In ₂ O ₃ ), bismuth oxide (Bi ₂ O ₃ ), tantalum oxide (Ta ₂ O ₅ ), cerium oxide (CeO ₂ ), niobium oxide (Nb ₂ O ₅ ), yttrium oxide (Y ₂ O ₃ ) and antimony oxide (Sb ₂ O ₃ ). In the present invention, any of these metal oxides is preferably used. Among them, aluminum oxide (Al ₂ O ₃ ), magnesium oxide (MgO), tin oxide (SnO ₂ ), calcium oxide (CaO) ) Is preferably used.

  Note that the insulating material used in the present invention may be only one type or two or more types.

  In the present invention, the thickness of the insulating material coated on the surface of the metal oxide semiconductor fine particles is not particularly limited, and depending on the type of insulating material used, etc., the porous layer can be formed by spray pyrolysis. When the first electrode layer is formed thereon, the metal oxide material constituting the metal oxide semiconductor fine particles can be arbitrarily adjusted within a range that can be prevented to a desired extent. When a metal oxide is used as the insulating material, the thickness of the metal oxide to be coated is usually preferably in the range of 0.1 nm to 50 nm, and more preferably in the range of 0.5 nm to 10 nm. It is preferable that it is within a range of 1 nm to 5 nm.

  Further, in the present invention, the metal oxide semiconductor fine particles are coated with an insulating material on the surface when the first electrode layer is formed on the porous layer by spray pyrolysis. There is no particular limitation as long as the metal oxide material constituting the fine particles can be prevented from being reduced to a desired degree. Such an aspect may be an aspect in which the surface of each metal oxide semiconductor fine particle is coated, or an aspect in which a plurality of metal oxide semiconductor fine particles are integrally coated. May be.

  In the present invention, the surface of the metal oxide semiconductor fine particles is “covered” with the insulating material is not only an aspect in which the insulating material is attached so as to cover the entire surface of the metal oxide semiconductor fine particles. The embodiment includes an aspect in which an insulating material is attached so that a part of the surface of the metal oxide semiconductor fine particles is exposed within a range not impairing the object of the present invention.

(2) Arbitrary component The porous layer used in the present invention may contain other optional components in addition to the metal oxide semiconductor fine particles whose surface is coated with an insulating material. The optional component used in the present invention is not particularly limited as long as a desired function can be imparted to the oxide semiconductor electrode laminate of the present invention. In particular, the porous layer used in the present invention contains the same metal element (hereinafter sometimes referred to as an electrode metal element) as the metal element contained in the metal oxide constituting the first electrode layer described later. Is preferred. This is because, when the porous layer contains an electrode metal element, the oxide semiconductor electrode produced using the oxide semiconductor electrode laminate of the present invention can be made excellent in conductivity.

  When the electrode metal element described above is included as the optional component, the distribution of the electrode metal element in the porous layer can be arbitrarily determined according to the use of the oxide semiconductor electrode laminate of the present invention. it can. In particular, in the present invention, the existence distribution having a decreasing concentration gradient from the surface on the first electrode layer side to the opposite surface is preferable. This is because the current collection efficiency of the porous layer can be further improved by such distribution of the electrode metal element in the porous layer.

  In the present invention, the presence of the electrode metal element in the porous layer and the presence distribution described above are determined by mapping the characteristic X-ray intensity of the metal element to be specified using the electron beam as a probe in two dimensions. can do. Specifically, it can be determined by EPMA (Electron Probe Micro Analyzer) manufactured by JEOL. Further, the concentration gradient of the metal element can be determined from the detected intensity profile in the vertical direction (cross-sectional vertical direction) of the cross-sectional element mapping diagram obtained by the EPMA.

  The porous layer in the present invention preferably contains a dye sensitizer as an optional component. That is, it is preferable that a dye sensitizer is attached to the surface of the metal oxide semiconductor fine particles contained in the porous layer. When the porous layer contains a dye sensitizer, when the oxide semiconductor electrode laminate of the present invention is used to produce a dye-sensitized solar cell, a dye-sensitized solar cell is produced. This is because the process can be simplified.

  The dye sensitizer used in the present invention is not particularly limited as long as it can absorb light and generate an electromotive force. Examples of such a dye sensitizer include organic dyes and metal complex dyes. Examples of the organic dye include acridine, azo, indigo, quinone, coumarin, merocyanine, and phenylxanthene dyes. In the present invention, among these organic dyes, a coumarin dye is preferably used. The metal complex dye is preferably a ruthenium dye, and particularly preferably a ruthenium bipyridine dye and a ruthenium terpyridine dye, which are ruthenium complexes. This is because such a ruthenium complex has a wide wavelength range of light to be absorbed, so that the wavelength range of light that can be photoelectrically converted can be greatly expanded.

  Furthermore, the porous layer in the present invention may contain metal oxide semiconductor fine particles whose surface is not covered with an insulating material. As an aspect in which such a metal semiconductor fine particle is included in the porous layer, the metal oxide semiconductor fine particle whose surface is coated with an insulating material in the porous layer and the metal oxide whose surface is not covered with an insulating material The semiconductor semiconductor fine particles may be uniformly contained, or the porous layer is coated with an insulating material near the surface on the side where the first electrode layer is formed, rather than near the surface on the opposite side. An embodiment in which a large number of the prepared metal oxide semiconductor particles are present may be employed.

(3) Porous layer The thickness of the porous layer used in the present invention is within a range in which a desired mechanical strength can be imparted to the porous layer according to the use of the oxide semiconductor electrode laminate of the present invention. There is no particular limitation. In particular, the thickness of the porous layer in the present invention is usually preferably in the range of 1 μm to 100 μm, particularly preferably in the range of 5 μm to 30 μm. This is because if the thickness of the porous layer is larger than the above range, the porous layer itself tends to cause cohesive failure, which tends to cause membrane resistance. In addition, if it is thinner than the above range, it becomes difficult to form a porous layer having a uniform thickness, for example, when a dye-sensitized solar cell is produced using the oxide semiconductor electrode laminate of the present invention. Furthermore, the porous layer containing the dye sensitizer cannot sufficiently absorb sunlight or the like, which may cause poor performance.

  The porous layer in the present invention may be composed of a single layer or may be composed of a plurality of layers. In particular, the present invention preferably has a configuration in which a plurality of layers are laminated. As a structure in which a plurality of layers are laminated, any structure can be appropriately selected and employed in accordance with the method for manufacturing the oxide semiconductor electrode laminate of the present invention. In particular, in the present invention, an oxide semiconductor layer in contact with the first electrode layer, a porous layer formed on the oxide semiconductor layer, and an intervening layer having a higher porosity than the oxide semiconductor layer, A two-layer structure consisting of Since the porous layer has a two-layer structure including such an oxide semiconductor layer and an intervening layer, the adhesion between the heat-resistant substrate and the porous layer is reduced without reducing the performance of the porous layer. As a result, the oxide semiconductor electrode can be formed from the stacked body for oxide semiconductor electrodes of the present invention by a transfer method.

  When the porous layer has a two-layer structure of the oxide semiconductor layer and the intervening layer, the thickness ratio between the oxide semiconductor layer and the intervening layer is not particularly limited, and the oxide semiconductor electrode of the present invention It can be arbitrarily determined in accordance with the use of etc. Especially in this invention, it is preferable that the thickness ratio of the said oxide semiconductor layer and the said intervening layer exists in the range of 10: 0.1-10: 5, Especially 10: 0.1-10: 3 It is preferable to be within the range. If the thickness of the intervening layer is larger than the above range, for example, the intervening layer is likely to cause cohesive failure, so that the yield is increased when the oxide semiconductor electrode is manufactured using the oxide semiconductor electrode stack of the present invention. When a dye-sensitized solar cell is produced using the oxide semiconductor electrode laminate of the present invention, a desired amount of dye is increased on the surface of the metal oxide semiconductor fine particles contained in the porous layer. This is because the sensitizer may not be adsorbed. If the thickness is less than the above range, the decrease in adhesion between the porous layer and the heat-resistant substrate due to the formation of the intervening layer is reduced, and an oxide semiconductor electrode is produced from the oxide semiconductor electrode laminate of the present invention. This is because there may be cases where it cannot contribute to productivity improvement.

  The porosity of the oxide semiconductor layer is preferably in the range of 10% to 60%, and more preferably in the range of 20% to 50%. When the porosity of the oxide semiconductor layer is smaller than the above range, for example, when a dye-sensitized solar cell is produced using the oxide semiconductor electrode of the present invention, sunlight is emitted from the porous layer. This is because there is a possibility that it cannot be effectively absorbed. Moreover, it is because it may become impossible to make the oxide semiconductor layer contain a desired amount of the dye sensitizer when the range is larger than the above range.

  The porosity of the intervening layer is not particularly limited as long as it is larger than the porosity of the oxide semiconductor layer, but it is usually preferably in the range of 25% to 65%, and in particular, 30% It is preferable to be within a range of ˜60%.

  In addition, the porosity in this invention shows the nonoccupancy rate of the metal oxide semiconductor fine particle per unit volume. As a method for measuring the porosity, the pore volume is measured with a gas adsorption amount measuring device (Autosorb-1MP; manufactured by Quantachrome), and is calculated from the ratio to the volume per unit area. About the porosity of an intervening layer, it calculates | requires as a porous layer laminated | stacked with the oxide semiconductor layer, and calculates from the value calculated | required by the oxide semiconductor layer single-piece | unit.

2. First Electrode Layer Next, the first electrode layer used in the present invention will be described. The first electrode layer used in the present invention is formed on the porous layer by a spray pyrolysis method and is made of a metal oxide.

Here, the first electrode layer used in the present invention is formed by a spray pyrolysis method. However, the first electrode layer is formed by a spray pyrolysis method. It can be specified by confirming that a region in which the first electrode layer and the porous layer are mixed is formed between the porous layer and the porous layer.
That is, as described above, when the first electrode layer is formed on the porous layer by the spray pyrolysis method, it is inevitable that a part of the material constituting the first electrode layer penetrates into the porous layer. A region where the material constituting the first electrode layer and the material constituting the porous layer are mixed is formed in the permeated region. Therefore, by confirming the presence of this region, it can be specified that the first electrode layer is formed by spray pyrolysis.
Hereinafter, such a first electrode layer will be described.

  The metal oxide used in the present invention is not particularly limited as long as it has desired conductivity. Especially, it is preferable that the metal oxide used for this invention has sunlight permeability. Thereby, when a dye-sensitized solar cell is produced using the oxide semiconductor electrode laminate of the present invention, it is possible to prevent power generation efficiency from being impaired.

Examples of such a metal oxide having sunlight permeability include SnO ₂ , ITO, IZO, and ZnO. In the present invention, any of these metal oxides can be suitably used. Among these, fluorine-doped SnO ₂ (hereinafter referred to as FTO) and ITO are preferably used. This is because FTO and ITO are excellent in both conductivity and sunlight permeability.

  The first electrode layer used in the present invention may be composed of a single layer or may be composed of a plurality of layers laminated. Examples of the configuration in which a plurality of layers are stacked include a mode in which layers having different work functions are stacked and a mode in which layers made of different metal oxides are stacked.

The thickness of the 1st electrode layer used for this invention will not be specifically limited if it exists in the range which can implement | achieve desired electroconductivity according to the use etc. of the laminated body for oxide semiconductor electrodes of this invention. In particular, the thickness of the first electrode layer in the present invention is usually preferably in the range of 5 nm to 2000 nm, and particularly preferably in the range of 10 nm to 1000 nm. If the thickness is larger than the above range, it may be difficult to form a homogeneous first electrode layer. If the thickness is smaller than the above range, the oxide semiconductor electrode laminate of the present invention is used. This is because there is a possibility that the conductivity of the first electrode layer may be insufficient.
In addition, the said thickness shall point out the total thickness which added the thickness of all the layers, when the 1st electrode layer is comprised by the laminated | stacked several layer.

3. Next, the heat resistant substrate used in the present invention will be described. The heat-resistant substrate used in the present invention is not particularly limited as long as it has desired heat resistance. Among them, the electrode laminate of the present invention is generally subjected to a high-temperature firing process in the process of forming a porous layer on a heat-resistant substrate, and therefore, as a heat-resistant substrate used in the present invention, It is preferable to have heat resistance that can withstand the heating temperature during the baking treatment performed when the porous layer is formed. By using such a heat-resistant substrate having sufficient heat resistance, the firing process can be performed at a sufficiently high temperature when forming the porous layer in the process of producing the oxide semiconductor electrode laminate of the present invention. Therefore, there is an advantage that the binding property between the metal oxide semiconductor fine particles forming the porous layer can be increased.

  It is preferable that the heat resistant substrate used in the present invention has acid resistance among the above heat resistant materials. Here, “acid resistance” in the present invention means that the coating liquid for forming a porous layer used for forming the porous layer in the process of producing the oxide semiconductor electrode laminate of the present invention is acidic. In some cases, even if the heat-resistant substrate is not corroded by the porous layer forming coating solution, or even if it is somewhat corroded, the acid decomposition product may cause alteration or peeling of the porous layer. Acid resistance to the extent that it does not occur.

  The heat resistant substrate used in the present invention may be a single layer or a plurality of layers as long as it has the acid resistance and heat resistance described above. When the heat-resistant substrate is a single layer, the material of the heat-resistant substrate is not particularly limited as long as it has flexibility, heat resistance, and acid resistance. For example, a single metal, a metal alloy, and a metal Examples thereof include metals such as oxides. Examples of the metal simple substance include Ti, W, Mo, Nb, Cr, Ni, Ag, Zr, Pt, Ta, and Au. Among these, Ti, W, Pt, and Au are preferable. Examples of the metal alloy include SUS, Ti alloy, Fe alloy, Ni alloy, Al alloy, W alloy, Mg alloy, Co alloy, and Cr alloy. Among them, SUS, Ti alloy, and Al alloy are preferable. Examples of the metal oxide include Si oxide, Al oxide, Ti oxide, Zr oxide, Sn oxide, Cr oxide, and W oxide. Ti oxide is preferred.

  On the other hand, when the heat-resistant substrate has a plurality of layers, for example, the heat-resistant substrate has a heat-resistant layer and an acid-resistant layer formed on the surface of at least the porous layer side of the heat-resistant layer. Can be mentioned.

  The heat-resistant layer is not particularly limited as long as the heat-resistant layer has sufficient heat resistance with respect to the heating temperature during the baking treatment performed when the porous layer is formed. Examples of the material for such a heat-resistant layer include metals, glasses, ceramics, and the like, among which metals are preferable. Furthermore, specific examples of the metal include a simple metal, a metal alloy, and a metal oxide. Moreover, since the said metal simple substance, a metal alloy, and a metal oxide generally have sufficient heat resistance, the kind etc. are not specifically limited. In addition, as said metal simple substance, specifically Ti, W, Pt, Au etc. are preferable, As said metal alloy, SUS, Ti alloy, Al alloy etc. are specifically preferable, As said metal oxide, Specifically, Si oxide, Al oxide, Ti oxide and the like are preferable.

  The acid-resistant layer is not particularly limited as long as it has acid resistance and heat resistance. Examples of the material for such an acid-resistant layer include metals, glasses, ceramics, and the like. Among these, metals are preferable. Furthermore, specific examples of the metal include a simple metal, a metal alloy, and a metal oxide. Examples of the metal simple substance include Ti, W, Mo, Nb, Cr, Ni, Ag, Zr, Pt, Ta, and Au. Among these, Ti, W, Pt, and Au are preferable. Examples of the metal alloy include SUS, Ti alloy, Fe alloy, Ni alloy, Al alloy, W alloy, Mg alloy, Co alloy, and Cr alloy. Among them, SUS, Ti alloy, and Al alloy are preferable. Examples of the metal oxide include Si oxide, Al oxide, Ti oxide, Zr oxide, Sn oxide, Cr oxide, and W oxide. Ti oxide is preferred.

  When the heat-resistant substrate used in the present invention has the heat-resistant layer and the acid-resistant layer, the combination of the heat-resistant layer and the acid-resistant layer is not particularly limited and can be arbitrarily selected. . For example, the combination of the material of the heat resistant layer is metal, glass or ceramics, and the material of the acid resistant layer is metal. Among them, the material of the heat resistant layer and the acid resistant layer is metal. Some combinations are preferred. This is because a heat-resistant substrate having excellent flexibility can be obtained.

  As a combination in which the material of the heat resistant layer and the acid resistant layer is a metal, for example, the material of the heat resistant layer is a simple metal, a metal alloy, or a metal oxide, and the material of the acid resistant layer is the heat resistant layer. The combination which is a metal simple substance, a metal alloy, or a metal oxide other than the metal used for the above can be mentioned. Specifically, as a combination of the material of the heat resistant layer / the material of the acid resistant layer, Ti simple substance / Ti oxide, SUS / Cr simple substance, SUS / Si oxide, SUS / Ti oxide, SUS / Al oxide, Examples thereof include SUS / Cr oxide.

Moreover, when the material of the said heat resistant layer and the said acid resistant layer is a metal, it is preferable that the metal element contained in the said heat resistant layer differs from the metal element contained in the said acid resistant layer. Here, “a metal element contained in the heat-resistant layer” means a metal element contained most in the heat-resistant layer. Therefore, for example, even when SUS contains Cr, Ni or the like, the “metal element contained in the heat-resistant layer” is Fe. The same applies to the “metal element contained in the acid-resistant layer”. As a combination of such a heat-resistant layer and an acid-resistant layer, as a combination of a material of a heat-resistant layer / a material of an acid-resistant layer, SUS / Cr simple substance, SUS / Si oxide, SUS / Ti oxide, SUS / Al Examples thereof include oxides and SUS / Cr oxides.
The heat resistant substrate preferably has flexibility. This is because a stacked body for oxide semiconductor electrodes can be manufactured by the Roll to Roll method.

4). Use of Oxide Semiconductor Electrode Laminate The use of the oxide semiconductor electrode laminate of the present invention is not particularly limited, but in particular to produce an oxide semiconductor electrode used for dye-sensitized solar cells and the like. Used for. That is, an oxide semiconductor electrode used for a dye-sensitized solar cell or the like has a configuration in which a first electrode layer and a porous layer are laminated in this order on a base material. If the oxide semiconductor electrode laminate is used, an oxide semiconductor electrode can be easily produced by transferring the porous layer and the first electrode layer formed on the heat-resistant substrate onto an arbitrary substrate. It is suitably used for such applications.

5). Manufacturing method of oxide semiconductor electrode laminate The oxide semiconductor electrode laminate of the present invention uses metal oxide semiconductor fine particles used for the porous layer, the surface of which is coated with an insulating material, and It can be generally produced using a known method except that the first electrode layer is formed on the porous layer by spray pyrolysis. Among these, the oxide semiconductor electrode laminate of the present invention can be produced with high efficiency by the method described in the section “D. Method for producing oxide semiconductor electrode laminate” described later.

B. Next, the oxide semiconductor electrode of the present invention will be described. An oxide semiconductor electrode according to the present invention is formed on a base material, a first electrode layer formed on the base material by a spray pyrolysis method, made of a metal oxide, and formed on the first electrode layer. A porous layer containing semiconductor fine particles, wherein the metal oxide semiconductor fine particles are coated with an insulating material on the surface.

  Such an oxide semiconductor electrode of the present invention will be described with reference to the drawings. FIG. 2 is a schematic sectional view showing an example of the oxide semiconductor electrode of the present invention. As illustrated in FIG. 2, the oxide semiconductor electrode 11 of the present invention includes a base material 4, a first electrode layer 3 formed on the base material 4 by spray pyrolysis and made of a metal oxide, and the first 1 and a porous layer 2 containing metal oxide semiconductor fine particles, and the metal oxide semiconductor fine particles contained in the porous layer 2 are covered with an insulating material on the surface. It is characterized by that.

According to the present invention, the metal oxide semiconductor fine particles contained in the porous layer are covered with an insulating material, and the first electrode layer is formed by a spray pyrolysis method. An oxide semiconductor electrode having excellent characteristics can be obtained.
Here, the reason why an oxide semiconductor electrode excellent in semiconductor characteristics can be obtained by the present invention is the same as the reason described in the above section “A. Stack for oxide semiconductor electrode”, Description of is omitted.

The oxide semiconductor electrode of the present invention has at least a substrate, a first electrode layer, and a porous layer, and may have any other configuration as necessary.
Hereafter, each structure used for the oxide semiconductor electrode of this invention is demonstrated in order.

  Note that the first electrode layer and the porous layer used in the oxide semiconductor electrode of the present invention are the same as those described in the section “A. Stack for oxide semiconductor electrode” above, so here Description is omitted.

1. Base material First, the base material used for this invention is demonstrated. The base material used in the present invention is not particularly limited as long as it has a self-supporting property capable of supporting the first electrode layer and the porous layer used in the present invention. Therefore, the base material used in the present invention may be a flexible material having flexibility, or may be a rigid material having no flexibility, such as quartz glass, Pyrex (registered trademark), and synthetic quartz plate. May be. In particular, the base material used in the present invention is preferably a flexible material, and among the flexible materials, a film base material is preferable. This is because the film substrate is excellent in processability and can reduce the manufacturing cost.

  Examples of the film substrate include an ethylene / tetrafluoroethylene copolymer film, a biaxially stretched polyethylene terephthalate film, a polyethersulfone (PES) film, a polyetheretherketone (PEEK) film, and a polyetherimide (PEI). Examples thereof include resin film substrates such as films, polyimide (PI) films, polyester naphthalate (PEN), and polycarbonate (PC). Among them, biaxially stretched polyethylene terephthalate film (PET), polyester naphthalate (PEN) Polycarbonate film (PC) is preferred.

  Further, the thickness of the base material used in the present invention can be appropriately selected according to the use of the oxide semiconductor electrode of the present invention, but is usually preferably in the range of 50 μm to 2000 μm. In particular, it is preferably in the range of 75 μm to 1800 μm, and more preferably in the range of 100 μm to 1500 μm. This is because if the thickness of the substrate is thinner than the above range, sufficient mechanical strength may not be imparted to the oxide semiconductor electrode of the present invention. Moreover, it is because the processability of the oxide semiconductor electrode of this invention may be impaired when the thickness of a base material is too large.

Moreover, it is preferable that the base material used for this invention is excellent in heat resistance, a weather resistance, water vapor | steam, and other gas barrier properties. This is because when the base material has gas barrier properties, for example, when the oxide semiconductor electrode of the present invention is used in a dye-sensitized solar cell, the temporal stability of the dye-sensitized solar cell can be improved. In particular, in the present invention, the oxygen transmission rate is 1 cc / m ² / day · atm or less under conditions of a temperature of 23 ° C. and a humidity of 90%, and the water vapor transmission rate is 1 g under the conditions of a temperature of 37.8 ° C. and a humidity of 100%. It is preferable to use a base material having a gas barrier property of / m ² / day or less. In the present invention, in order to achieve such a gas barrier property, a material provided with a gas barrier layer on an arbitrary substrate may be used.

2. Arbitrary Configuration The oxide semiconductor electrode of the present invention has at least the base material, the first electrode layer, and the porous layer, but may have other arbitrary configurations as necessary. . The arbitrary structure used in the present invention is not particularly limited, and a structure having an arbitrary function is used depending on the use of the oxide semiconductor electrode of the present invention and the method for manufacturing the oxide semiconductor electrode of the present invention. Can do. Especially, it is preferable that the oxide semiconductor electrode of this invention has an adhesive layer formed between the said base material and the said 1st electrode layer as said arbitrary structures, and containing adhesive resin. This is because by forming such an adhesive layer, the oxide semiconductor electrode of the present invention can be easily manufactured by the transfer method described above.

  The case where the oxide semiconductor electrode of the present invention has the above adhesive layer will be described with reference to the drawings. FIG. 3 is a schematic cross-sectional view showing an example of the case where the oxide semiconductor electrode of the present invention has the adhesive layer. As illustrated in FIG. 3, the oxide semiconductor electrode 11 ′ of the present invention is such that an adhesive layer 5 containing an adhesive resin is formed between the base material 4 and the first electrode layer 3. Also good.

  The adhesive resin used for the adhesive layer is not particularly limited as long as it is a resin that melts at a desired temperature. Among them, the adhesive resin used in the present invention preferably has a melting point in the range of 50 ° C to 200 ° C, particularly preferably in the range of 60 ° C to 180 ° C, and more preferably in the range of 65 ° C to 150 ° C. It is preferable to be within. When the melting point is lower than the above range, for example, when a dye-sensitized solar cell produced using the oxide semiconductor electrode of the present invention is used outdoors, the adhesion between the substrate and the first electrode layer This is because there is a possibility that the property is not sufficiently maintained. Further, when the melting point is higher than the above range, for example, when the oxide semiconductor electrode of the present invention is produced by a transfer method, a heating step higher than the melting point is required in the transfer step. This is because the base material itself may be damaged by heat depending on the type of.

  Examples of the adhesive resin used in the present invention include polyethylene, polypropylene, polyisobutylene, polystyrene, polyolefin such as ethylene-propylene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethyl cellulose, triacetic acid. Cellulose derivatives such as cellulose, copolymers of poly (meth) acrylic acid and its esters, polyvinyl acetals such as polyvinyl acetate, polyvinyl alcohol and polyvinyl butyral, polyacetals, polyamides, polyimides, nylons, polyester resins, urethane resins, epoxies Examples thereof include a resin, a silicone resin, and a fluororesin. Moreover, as adhesive resin used for this invention, what was described in Unexamined-Japanese-Patent No. 2006-310256 can be mentioned, for example. In the present invention, any of these adhesive resins can be suitably used. Among them, polyolefin, ethylene-vinyl acetate are preferred from the viewpoints of adhesion, resistance to electrolyte, light transmission and transferability. A copolymer, urethane resin, epoxy resin, silane-modified resin, and acid-modified resin are preferred.

  Moreover, it is preferable that the contact bonding layer used for this invention contains the at least 1 sort (s) of additive chosen from the group which consists of a light stabilizer, a ultraviolet absorber, a heat stabilizer, and antioxidant. By including these additives, it is possible to obtain stable mechanical strength over a long period of time, prevention of yellowing, prevention of cracking, and excellent processability.

  The light stabilizer supplements the active species at the start of photodegradation in the thermoplastic resin used in the adhesive layer and prevents photooxidation. Specific examples include light stabilizers such as hindered amine compounds and hindered piperidine compounds.

  UV absorbers absorb harmful UV rays in sunlight and convert them into innocuous heat energy within the molecule, which excites the active species that initiate photodegradation in the thermoplastic resin used in the adhesive layer. Is to prevent. Specifically, benzophenone-based, benzotriazole-based, salicylate-based, acrylonitrile-based, metal complex-based, hindered amine-based, and ultrafine titanium oxide (particle size: 0.01 μm to 0.06 μm) or ultrafine zinc oxide (particle size) : 0.01 [mu] m to 0.04 [mu] m).

  Thermal stabilizers include tris (2,4-di-t-butylphenyl) phosphite, bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl ester phosphorous acid, tetrakis (2,4-di-tert-butylphenyl) [1,1-biphenyl] -4,4'-diylbisphosphonite, and bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite And a lactone heat stabilizer such as a reaction product of 8-hydroxy-5,7-di-t-butyl-furan-2-one and o-xylene. It is preferable to use a phosphorus-based heat stabilizer and a lactone-based heat stabilizer in combination.

  The antioxidant prevents oxidative deterioration of the thermoplastic resin used for the adhesive layer. Specific examples include phenol-based, amine-based, sulfur-based, phosphorus-based, and lactone-based antioxidants.

  These light stabilizers, ultraviolet absorbers, heat stabilizers and antioxidants can be used alone or in combination of two or more.

  Furthermore, as other compounds used in the present invention, in addition to the above, a crosslinking agent, a dispersing agent, a leveling agent, a plasticizer, an antifoaming agent, and the like can be given.

  The thickness of the adhesive layer used in the present invention is not particularly limited as long as it is within a range in which a necessary adhesive force can be expressed, depending on the type of the adhesive resin constituting the adhesive layer. It is preferable that it is in the range of 10 micrometers-200 micrometers especially. If the thickness of the adhesive layer is thinner than the above range, a desired adhesive force may not be obtained, and if the thickness is thicker than the above range, excessive heating is required to sufficiently express the interlayer adhesive strength by the adhesive layer. This is because the thermal damage to the base material and the like may increase.

3. Oxide Semiconductor Electrode The porous layer in the oxide semiconductor electrode of the present invention is preferably patterned. This is because the oxide semiconductor electrode of the present invention can be made suitable for producing a dye-sensitized solar cell having a high module electromotive force by patterning the porous layer. The porous layer in the present invention may be patterned as long as at least the porous layer is patterned. Moreover, when a porous layer consists of the said oxide semiconductor layer and the said intervening layer, it is preferable that both layers are patterned by the same shape.

  The pattern in the case where the porous layer is patterned in the present invention can be arbitrarily determined according to the use of the oxide semiconductor electrode of the present invention. preferable.

4). Applications of Oxide Semiconductor Electrode The oxide semiconductor electrode of the present invention is a substrate for a dye-sensitized photocharge capacitor used for a dye-sensitized photocharge capacitor, an electrochromic display substrate used for an electrochromic display, and a photocatalyst. It can be used as a pollutant decomposition substrate capable of decomposing pollutants in the atmosphere using a reaction, and a dye-sensitized solar cell substrate used for dye-sensitized solar cells, among which dye-sensitized type It is suitably used as a dye-sensitized solar cell substrate used in solar cells.

5). Method for Producing Oxide Semiconductor Electrode The oxide semiconductor electrode of the present invention uses a metal oxide semiconductor fine particle used for the porous layer whose surface is coated with an insulating material, and on the porous layer. Except for forming the first electrode layer by spray pyrolysis, it can be generally produced using a known method. In particular, the oxide semiconductor electrode of the present invention can be produced with high efficiency by the method described in the section “D. Method for producing oxide semiconductor electrode” described later.

C. Next, the dye-sensitized solar cell of the present invention will be described. The dye-sensitized solar cell of the present invention is a pair having the oxide semiconductor electrode according to the present invention, a counter substrate, and a second electrode layer formed on the counter substrate and made of a metal oxide. An electrode base is disposed such that the porous layer and the second electrode layer face each other, and an electrolyte layer including a redox pair between the oxide semiconductor electrode and the counter electrode base It has the structure in which was formed.

  Such a dye-sensitized solar cell of the present invention will be described with reference to the drawings. FIG. 4 is a schematic sectional view showing an example of the dye-sensitized solar cell of the present invention. As illustrated in FIG. 4, the dye-sensitized solar cell 20 of the present invention is formed on the oxide semiconductor electrode 11 ′, the counter substrate 21 a, and the counter substrate 21 a according to the present invention. The counter electrode base material 21 having the second electrode layer 21b made of an oxide is disposed so that the porous layer 2 provided in the oxide semiconductor electrode 11 ′ and the second electrode layer 21 face each other. In addition, an electrolyte layer 22 including a redox pair is formed between the oxide semiconductor electrode 11 ′ and the counter electrode base material 21. Here, in the oxide semiconductor electrode 11 ′ used in the present invention, the porous layer 2 contains a dye sensitizer. In addition, as illustrated in FIG. 4, the dye-sensitized solar cell 20 of the present invention is usually provided with a sealing material 23 around the electrolyte layer 22.

  ADVANTAGE OF THE INVENTION According to this invention, the dye-sensitized solar cell excellent in power generation efficiency can be obtained by using the oxide semiconductor electrode which concerns on the said this invention excellent in the semiconductor characteristic.

The dye-sensitized solar cell of the present invention has at least the oxide semiconductor electrode, the counter electrode base material, and the electrolyte layer, and may have any other configuration as necessary.
Hereafter, each structure used for the dye-sensitized solar cell of this invention is demonstrated in order.

1. Oxide Semiconductor Electrode First, the oxide semiconductor electrode used in the present invention will be described. The oxide semiconductor electrode used in the present invention is the oxide semiconductor electrode according to the present invention, and includes a porous layer containing a dye sensitizer.
Such an oxide semiconductor electrode is the same as that described in the above section “B. Oxide Semiconductor Electrode”, and thus a detailed description thereof is omitted here.

2. Electrolyte Layer Next, the electrolyte layer used in the present invention will be described. The electrolyte layer in the present invention includes a redox pair.

  The redox couple used in the electrolyte layer in the present invention is not particularly limited as long as it is generally used in the electrolyte layer of a dye-sensitized solar cell. Among them, the redox pair used in the present invention is preferably a combination of iodine and iodide and a combination of bromine and bromide.

Examples of the combination of iodine and iodide used in the present invention as the redox couple, for example, can be cited LiI, NaI, KI, and metal iodide such as CaI _2, a combination of I _2.
Further, examples of the combination of bromine and bromide include a combination of a metal bromide such as LiBr, NaBr, KBr, and CaBr ₂ and Br ₂ .

  The electrolyte layer in the present invention may contain additives such as a crosslinking agent, a photopolymerization initiator, a thickener, and a room temperature molten salt as other compounds other than the redox couple.

The electrolyte layer may be an electrolyte layer having any form of gel, solid, or liquid. When the electrolyte layer is in a gel form, either a physical gel or a chemical gel may be used. Here, the physical gel is gelled near room temperature due to physical interaction, and the chemical gel is a gel formed by chemical bonding by a crosslinking reaction or the like.
When the electrolyte layer is in a liquid state, for example, acetonitrile, methoxyacetonitrile, propylene carbonate or the like is used as a solvent, and an ionic liquid containing a redox couple or an imidazolium salt as a cation is used as a solvent. can do.
Furthermore, when the electrolyte layer is in a solid state, it may be any material that does not include a redox pair and functions as a hole transporting agent. For example, a hole transporting agent including CuI, polypyrrole, polythiophene, etc. There may be.

3. Next, the counter electrode substrate used in the present invention will be described. The counter electrode base material in this invention consists of a 2nd electrode layer and a counter base material.

(1) Second electrode layer The second electrode layer used in the present invention is not particularly limited as long as it is made of a metal oxide having desired conductivity. As described above, the first electrode layer included in the oxide semiconductor electrode used in the present invention is also made of a metal oxide, and is formed on the porous layer by spray pyrolysis. However, the second electrode layer used in the present invention is different from the first electrode layer in that it is not limited to the one formed by spray pyrolysis.

  In the present invention, the metal oxide used for the second electrode layer is not particularly limited as long as it has desired conductivity. As such a metal oxide, the same thing as what was demonstrated as a metal oxide used for a 1st electrode layer in the above-mentioned "A. Oxide semiconductor electrode laminated body" section can be used.

  The second electrode layer used in the present invention may be composed of a single layer or may be composed of a plurality of layers laminated. Examples of the configuration in which a plurality of layers are laminated include an invention in which layers having different work functions are laminated, and an invention in which layers made of different metal oxides are laminated.

  The thickness of the second electrode layer used in the present invention is usually preferably in the range of 5 nm to 2000 nm, and particularly preferably in the range of 10 nm to 1000 nm.

(2) Opposite base material The counter base material in the present invention can be the same as that described in the section of the base material of “B. Oxide semiconductor electrode”, and the description thereof is omitted here. To do.

(3) Other layers The counter electrode base material used in the present invention may have other configurations than the second electrode layer and the counter base material, if necessary. Examples of other configurations used in the present invention include a catalyst layer. In the present invention, since the catalyst layer is formed on the second electrode layer, the dye-sensitized solar cell of the present invention can be made more excellent in power generation efficiency. Examples of such a catalyst layer include an embodiment in which Pt is vapor-deposited on the second electrode layer, but is not limited thereto.

4). Dye-sensitized solar cell The dye-sensitized solar cell of the present invention includes a pair of layers formed by patterning the porous layer of the oxide semiconductor electrode and the second electrode layer of the counter electrode substrate. A plurality of cells may be connected to the oxide semiconductor electrode and the counter electrode base material. This is because by having such a configuration, the dye-sensitized solar cell of the present invention can have a high electromotive force.

  An example of a dye-sensitized solar cell having such a configuration will be described with reference to the drawings. FIG. 5 is a schematic cross-sectional view showing an example in which the dye-sensitized solar cell of the present invention has a configuration in which a plurality of cells are connected. As illustrated in FIG. 5, the dye-sensitized solar cell 20 ′ of the present invention includes an adhesive layer 5, a first electrode layer 3, a porous layer 2, and a counter electrode base material 21 included in the oxide semiconductor electrode 11 ′. A plurality of cells C are formed between the pair of oxide semiconductor electrodes 11 ′ and the counter electrode base material 21 by patterning the second electrode layer 21 b having, and these cells C are connected by the wiring 24. It may have a connected configuration. Note that the example shown in FIG. 5 has a configuration in which three cells C are connected.

  The shape of the patterning can be arbitrarily determined depending on the electromotive force required for the dye-sensitized solar cell of the present invention, and in the present invention, the patterning in the stripe shape is most preferable.

5). Next, an example of a method for producing the dye-sensitized solar cell of the present invention will be described. The dye-sensitized solar cell of the present invention is manufactured by forming an electrolyte layer between the porous layer of the oxide semiconductor electrode of the present invention and the second electrode substrate of the counter electrode substrate. can do.

  In the present invention, as a method of forming an electrolyte layer between the porous layer of the oxide semiconductor electrode of the present invention and the second electrode substrate of the counter electrode substrate, each layer is formed with high thickness accuracy. There is no particular limitation as long as it can be performed. As such a method, after forming an electrolyte layer on the porous layer of the oxide semiconductor electrode, a method of arranging a counter electrode substrate on the electrolyte layer (first method), and the oxide semiconductor A method of forming an electrolyte layer between the porous layer and the second electrode layer after arranging the electrode and the counter electrode base material so that the porous layer and the second electrode layer face each other (second method) Can be mentioned.

  As the first method, for example, an application method of applying a counter electrode substrate after forming an electrolyte layer by applying a composition for forming an electrolyte layer on the porous layer and drying it is used. it can. As the second method, the porous layer of the oxide semiconductor electrode and the second electrode layer of the counter electrode base material are arranged with a predetermined gap so as to face each other. By injecting the composition for forming an electrolyte layer, an injection method for forming an electrolyte layer can be used.

  As the coating method of the composition for forming a porous layer in the above coating method, a known coating method can be used. Specifically, die coating, gravure coating, gravure reverse coating, roll coating, reverse roll coating, bar Examples include coat, blade coat, knife coat, air knife coat, slot die coat, slide die coat, dip coat, micro bar coat, micro bar reverse coat, and screen printing (rotary method).

  Further, when the electrolyte layer is formed by the coating method, the electrolyte layer forming composition for forming the electrolyte layer is not particularly limited as long as it has at least a redox couple and a polymer compound that holds the redox couple. Not.

  When the electrolyte layer is formed by the above injection method, the electrolyte layer forming composition for forming the electrolyte layer is not particularly limited as long as it has at least a redox pair. In this case, it is assumed that a gelling agent is further contained. For example, in the case of a physical gel, examples of the gelling agent include polyacrylonitrile and polymethacrylate. Moreover, in the case of a chemical gel, an acrylic ester type, a methacrylic ester type, etc. can be mentioned.

  The method for injecting the composition for forming an electrolyte layer into the gap between the porous layer and the second electrode layer of the counter electrode base material is not particularly limited, but for example, a method of injecting using a capillary phenomenon In addition, a method may be used in which the gap between the porous layer and the second electrode is in a vacuum state and is injected by releasing the pressure to atmospheric pressure in a state where the composition for forming an electrolyte layer is in contact.

  Moreover, after injecting the composition for forming an electrolyte layer by an injection method, for example, temperature adjustment, ultraviolet irradiation, electron beam irradiation, or the like is performed, and a two-dimensional or three-dimensional crosslinking reaction is caused to generate a gel or solid. The electrolyte layer can be formed.

  In the present invention, the method for forming the second electrode layer on the counter substrate is not particularly limited, and a general method can be used.

D. Next, the manufacturing method of the laminated body for oxide semiconductor electrodes of this invention is demonstrated. The method for producing a laminate for an oxide semiconductor electrode according to the present invention uses a heat resistant substrate and forms a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate. And an insulating coating step of coating the surface of the metal oxide semiconductor fine particles contained in the porous layer forming layer with an insulating material, so that the surface is coated with the insulating material on the heat-resistant substrate. A porous layer forming step of forming a porous layer containing the metal oxide semiconductor fine particles formed, and a first electrode layer made of a metal oxide is formed on the porous layer by spray pyrolysis, And an electrode layer forming step.

  The manufacturing method of such a laminated body for oxide semiconductor electrodes of the present invention will be described with reference to the drawings. FIG. 6 is a schematic view showing an example of a method for producing a laminated body for an oxide semiconductor electrode according to the present invention. As illustrated in FIG. 6, the method for manufacturing a laminated body for an oxide semiconductor electrode according to the present invention uses a heat resistant substrate 1 (FIG. 6A), and contains metal oxide semiconductor fine particles on the heat resistant substrate 1. The porous layer forming layer forming step (FIG. 6 (b) -1) for forming the porous layer forming layer 2 ′, and the surface of the metal oxide semiconductor fine particles contained in the porous layer forming layer 2 ′ Having a metal oxide semiconductor fine particle whose surface is coated with an insulating material on the heat-resistant substrate 1. A porous layer forming step for forming a porous layer 2 (FIG. 6B), and a first electrode layer 3 made of a metal oxide is formed on the porous layer 2 by spray pyrolysis, An electrode layer forming step (FIG. 6C), and on the heat-resistant substrate 1, In which porous layer 2 and the first electrode layer is manufactured an oxide semiconductor electrode stack 10 having a stacked in this order (FIG. 6 (d)).

According to the present invention, the porous layer forming step includes the porous layer forming layer forming step and the insulating coating step, and includes a metal oxide semiconductor fine particle whose surface is coated with an insulating material. By forming the porous layer, the metal oxide semiconductor fine particles contained in the porous layer are reduced when the first electrode layer is formed by spray pyrolysis in the first electrode layer forming step. Can be prevented.
Further, according to the present invention, the first electrode layer forming step forms the first electrode layer by spray pyrolysis, so that the electron transfer performance with the porous layer is dense and dense. The 1st electrode layer excellent in can be formed.
For this reason, according to the present invention, it is possible to manufacture a laminated body for an oxide semiconductor electrode having excellent semiconductor characteristics.

The manufacturing method of the laminated body for oxide semiconductor electrodes of this invention has at least the said porous layer formation process and the said 1st electrode layer formation process, and has other arbitrary processes as needed. It may be.
Hereafter, each process used for this invention is demonstrated in order.

1. Porous layer forming step First, the porous layer forming step used in the present invention will be described. This step is a step of using a heat resistant substrate and forming a porous layer containing metal oxide semiconductor fine particles whose surface is coated with an insulating material on the heat resistant substrate. Further, this step uses a heat resistant substrate, and a porous layer forming layer forming step for forming a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate, and the porous layer forming layer described above And an insulating coating step of coating the surface of the metal oxide semiconductor fine particles contained in the substrate with an insulating material.
Hereinafter, such a porous layer forming step will be described in detail.

(1) Porous layer forming layer forming step First, the porous layer forming layer forming step will be described. This step is a step of forming a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate using a heat resistant substrate.
The porous layer forming layer formed in this step is composed of metal oxide semiconductor fine particles whose surface is not coated with an insulating material, and in the insulating coating step described later, The surface of the semiconductor fine particles is coated with an insulating material to form a porous layer.

  In this step, the method for forming the porous layer forming layer on the heat-resistant substrate is not particularly limited as long as the porous layer forming layer having a porosity within a desired range can be formed. . In particular, in this step, a porous layer forming layer is formed by coating a porous layer forming coating solution containing metal oxide semiconductor fine particles and a resin on a heat-resistant substrate and then firing the coating solution. The method is preferably used. Hereinafter, a method for forming the porous layer forming layer by such a method will be described.

a. Heat-resistant substrate The heat-resistant substrate used in this step is not particularly limited as long as it has heat resistance with respect to the firing temperature during the firing treatment described later. As such a heat-resistant substrate, the same substrate as described in the above section “A. Stack for oxide semiconductor electrode” can be used.

b. Porous layer forming coating solution The porous layer forming coating solution used in this step contains at least metal oxide semiconductor fine particles and a resin. Here, the metal oxide semiconductor fine particles are the same as those described in the section “A. Oxide semiconductor electrode laminate” except that the surface is not coated with an insulating material. The description is omitted here.

  The resin used for the coating liquid for forming the porous layer is not particularly limited as long as it can be decomposed at the time of baking the coating film of the coating liquid. Examples of such resins include cellulose resins, polyester resins, polyamide resins, polyacrylate resins, polyacryl resins, polycarbonate resins, polyurethane resins, polyolefin resins, polyvinyl acetal resins, and fluorine resins. In addition to resins and polyimide resins, polyhydric alcohols such as polyethylene glycol can be used.

  Moreover, in the coating liquid for forming a porous layer used in this step, a solvent may be used for dissolving and dispersing the resin and the metal oxide semiconductor fine particles. The solvent used in this step is not particularly limited as long as it can dissolve the resin in a desired amount. Examples of such a solvent include water and various solvents such as methanol, ethanol, isopropyl alcohol, propylene glycol monomethyl ether, terpineol, dichloromethane, acetone, acetonitrile, ethyl acetate, and tert-butyl alcohol. Among these, water or an alcohol solvent is preferable.

c. Next, a method for applying the porous layer forming coating solution onto the heat resistant substrate will be described. The coating method used in this step is not particularly limited as long as it is a method capable of forming a coating film having a uniform film thickness and excellent flatness. Examples of such methods include die coating, gravure coating, gravure reverse coating, roll coating, reverse roll coating, bar coating, blade coating, knife coating, air knife coating, slot die coating, slide die coating, dip coating, micro bar coating, Microbar reverse coating, offset coating, screen printing (rotary method) and the like can be mentioned.

d. Next, a method for firing the coating film of the porous layer forming coating solution will be described. In the present step, the method for baking the coating film is not particularly limited as long as it can be uniformly baked without heating unevenness, and a known heating method can be used.

  In addition, the firing temperature in this step is not particularly limited as long as it is within a range where the resin contained in the porous layer forming coating solution can be thermally decomposed, but is usually within a range of 300 ° C to 700 ° C. It is particularly preferable that the temperature be in the range of 350 ° C to 600 ° C.

(2) Insulating coating process Next, the insulating coating process used for this process is demonstrated. This step is a step of covering the surface of the metal oxide semiconductor fine particles contained in the porous layer forming layer formed by the porous layer forming layer forming step with an insulating material.

In this step, as a method of coating the surface of the metal oxide semiconductor fine particles contained in the porous layer forming layer with an insulating material, a method that can uniformly coat the surface of the metal oxide semiconductor fine particles with an insulating material If it is, it will not specifically limit. Examples of such a method include a solution immersion method and an electric deposition method.
Here, the solution dipping method means that the heat-resistant substrate on which the porous layer forming layer is formed is immersed (including coating) in a treatment liquid, and an insulating material is formed on the surface of the porous layer forming layer. Alternatively, the treatment liquid containing the precursor is physically and chemically adsorbed. Examples of the precursor of the insulating material used in the treatment liquid include alkoxides, inorganic compounds, complexes, and the like.
Further, as a method of adsorbing the insulating material or precursor to the surface of the porous layer forming layer, the hydroxyl group on the surface of the porous layer forming layer and the functional group of the insulating material or precursor in the treatment liquid are used. Hydrolysis and polycondensation can be used, and adsorption by electrostatic interaction can also be used.
In addition, when the thing containing the precursor of an insulating material is used as the said process liquid, after being immersed in a process liquid (including application | coating), after washing | cleaning as needed and drying, it is 600 in air. An insulating material can be formed by baking at a temperature of 0 ° C. or lower.

(3) Others In this step, the layer forming step for forming the porous layer is divided into the layer forming step for forming the intervening layer on the heat-resistant substrate and the layer forming step for forming the intervening layer. A layer forming step for forming an oxide semiconductor layer for forming a layer for forming an oxide semiconductor layer, and firing the intermediate layer forming layer and the oxide semiconductor layer forming layer to form a porous intermediate layer and oxide semiconductor By using a firing step for forming a porous layer composed of layers, the porous layer formed by this step can have a structure composed of two layers, an oxide semiconductor layer and an intervening layer.

2. First Electrode Layer Forming Step Next, the first electrode layer forming step used in the present invention will be described. This step is a step of forming a first electrode layer made of a metal oxide by a spray pyrolysis method on the porous layer formed by the porous layer forming step.

  As described above, this step is a step of forming the first electrode layer made of a metal oxide on the porous layer by spray pyrolysis, and the spray pyrolysis is a method for forming a heated porous layer. A metal compound solution containing a metal compound is sprayed on the porous layer to oxidize the metal contained in the metal compound on the porous layer, thereby forming a first electrode layer made of a metal oxide. More specifically, the porous layer is heated to a temperature equal to or higher than the metal oxide film formation temperature, and a metal salt or metal complex containing a metal element contained in the metal oxide constituting the first electrode layer (hereinafter simply referred to as “ A method of providing the first electrode layer on the porous layer by spraying and contacting the first electrode layer forming coating solution in which the metal source is dissolved)) on the porous layer. It is.

  Here, the “metal oxide film forming temperature” means that the metal element contained in the first electrode layer forming coating solution is combined with oxygen to form a metal oxide film such as the first electrode layer. The temperature at which the metal source is dissolved is greatly different depending on the type of metal ion or the like in which the metal source is dissolved, the composition of the first electrode layer forming coating solution, and the like. Such “metal oxide film formation temperature” can be measured by the following method. That is, a first electrode layer forming coating solution in which a desired metal source is actually dissolved is prepared, and the heating temperature of the heat-resistant substrate having the porous layer is changed and brought into contact with the first electrode layer. The lowest substrate heating temperature at which a certain metal oxide film can be formed is measured. This minimum substrate heating temperature can be set as the “metal oxide film forming temperature” in the spray method. At this time, whether or not the metal oxide film is formed is usually judged from the result obtained from an X-ray diffraction apparatus (Rigaku, RINT-1500). In the case of an amorphous film having no crystallinity, photoelectron spectroscopy is performed. It shall judge from the result obtained from the analyzer (the product made by VG Scientific, ESCALAB 200i-XL).

  Hereinafter, the first electrode layer forming step will be described in detail.

(1) First Electrode Layer Forming Coating Liquid First, the first electrode layer forming coating liquid used in this step will be described. The coating solution for forming the first electrode layer used in this step comprises a metal salt or metal complex containing a metal element contained in the metal oxide constituting the first electrode layer, and a solvent, and other compounds as necessary. Is included.

(Metal source)
The metal source used in the first electrode layer forming coating solution is not particularly limited as long as it can form a metal oxide film. Examples of the metal source used in this step mainly include metal salts and metal complexes.
Here, the oxide semiconductor electrode laminate produced according to the present invention is preferably used for producing an oxide semiconductor electrode suitably used for a dye-sensitized solar cell or the like. It is preferable that the 1st electrode layer formed in is excellent in translucency and electroconductivity. Therefore, it is preferable that the metal source is capable of forming such a first electrode layer. Specific examples thereof include tris (acetylacetonato) indium (III), 2-ethylhexanoic acid. Indium (III), tetraethyltin, dibutyltin oxide (IV), tricyclohexyltin (IV) hydroxide, zinc acetylacetonate, zinc lactate trihydrate, zinc salicylate trihydrate, zinc stearate, tetraethyltin, Dibutyltin oxide (IV), tricyclohexyltin (IV) hydroxide, ammonium fluoride, antimony (III) butoxide, antimony (III) ethoxide, tetraethyltin, dibutyltin oxide (IV), tricyclohexyltin (IV) hydroxide , Tetraethyltin, oxidation Butyl tin (IV), and tri-cyclohexyl tin (IV) hydroxide and the like.

  In addition, the metal source used for this process may be only one type, or may be two or more types.

  The concentration of the metal source in the first electrode layer forming coating solution may be arbitrarily adjusted according to the type of the metal source. In particular, when a metal salt is used as the metal source, the concentration is preferably in the range of 0.001 mol / L to 1 mol / L, and particularly in the range of 0.01 mol / L to 0.5 mol / L. It is preferable. On the other hand, when a metal complex is used as the metal source, the concentration is preferably in the range of 0.001 mol / L to 1 mol / L, particularly in the range of 0.01 mol / L to 0.5 mol / L. It is preferable. If the concentration is below the above range, it may take too much time to form the first electrode layer, and if the concentration is above the above range, it may not be possible to obtain the first electrode layer with a uniform thickness. Because there is.

(solvent)
The solvent used in the first electrode layer forming coating solution is not particularly limited as long as it can dissolve the metal source at a desired concentration. As such a solvent, for example, when a metal salt is used as a metal source, water, methanol, ethanol, isopropyl alcohol, propanol, butanol and the like, a lower alcohol having a total carbon number of 5 or less, toluene, and a mixed solvent thereof Etc. On the other hand, when a metal complex is used as the metal source, the above-mentioned lower alcohol, toluene, and a mixed solvent thereof can be exemplified.

(Additive)
The first electrode layer forming coating solution used in this step may contain any additive other than the metal source. Examples of such an optional additive include an oxidizing agent, a reducing agent, an auxiliary ion source, and a surfactant.

  The oxidizing agent has a function of accelerating the oxidation of metal ions and the like formed by dissolving the above-described metal source, and is included in the first electrode layer forming coating solution, whereby the first electrode is formed in this step. It has a function of enabling an environment in which a layer is easily formed.

  The oxidizing agent used in this step is not particularly limited as long as it can be dissolved in the above-described solvent and can promote the oxidation of the above metal ions, etc. The metal used in this step It can be appropriately selected and used according to the type of the source. Examples of such an oxidizing agent include hydrogen peroxide, sodium nitrite, potassium nitrite, sodium bromate, potassium bromate, silver oxide, dichromic acid, and potassium permanganate. Among these, it is preferable to use hydrogen peroxide and sodium nitrite in this step.

(Reducing agent)
The reducing agent has a property of releasing electrons by a decomposition reaction and generating hydroxide ions by water electrolysis to increase the pH of the first electrode layer forming coating solution. By including such a reducing agent in the coating solution for forming the first electrode layer, an environment in which the first electrode layer can be easily formed in this step can be provided.

  The reducing agent used in this step is not limited to any one as long as it can be dissolved in the above-described solvent and can emit electrons by a decomposition reaction. Examples of such a reducing agent include borane complexes such as borane-tert-butylamine complex, borane-N, N diethylaniline complex, borane-dimethylamine complex, borane-trimethylamine complex, sodium cyanoborohydride, hydroxide A sodium boron etc. can be mentioned. Among these, in this step, it is preferable to use a borane complex.

  The first electrode layer forming coating liquid may contain both a reducing agent and an oxidizing agent.

  The auxiliary ion source reacts with electrons to generate hydroxide ions, and raises the pH of the first electrode layer forming coating solution to make it easy to form the first electrode layer. It is what has. Examples of the auxiliary ion source used in this step include chlorate ion, perchlorate ion, chlorite ion, hypochlorite ion, bromate ion, hypobromate ion, nitrate ion, and nitrite ion. Can be mentioned.

  The surfactant acts on the interface between the first electrode layer forming coating solution and the porous layer, and has a function of facilitating the formation of the first electrode layer on the porous layer. Specific examples of the surfactant used in this step include, for example, Surfinol 485, Surfinol SE, Surfinol SE-F, Surfinol 504, Surfinol GA, Surfinol 104A, Surfinol 104BC, Surfinol 104PPM, Surfynol series such as Surfinol 104E and Surfinol 104PA (all manufactured by Nissin Chemical Industry Co., Ltd.), NIKKOL AM301, NIKKOL AM313ON (all manufactured by Nikko Chemical Co., Ltd.) and the like.

(2) Method for Contacting First Electrode Layer Forming Coating Liquid and Porous Layer Next, a method for bringing the first electrode layer forming coating liquid and the porous layer into contact in this step will be described. In this step, the first electrode layer-forming coating solution and the porous layer may be brought into contact with each other as long as the first electrode-forming coating solution can be uniformly contacted on the porous layer. Although not particularly limited, it is a method that does not lower the temperature of the heated porous layer when the first electrode layer forming coating solution and the porous layer are in contact with each other. preferable. This is because if the temperature of the porous layer is lowered, the desired first electrode layer may not be obtained.

  In this step, the first electrode layer forming coating solution is brought into contact with the porous layer heated to a temperature equal to or higher than the “metal oxide film forming temperature”. The “material film formation temperature” varies greatly depending on the type of metal source, the composition of the first electrode layer forming coating solution, and the like. Therefore, the “metal oxide film formation temperature” in this step may be appropriately determined depending on the type of the metal source. For example, an oxidizing agent and / or a reduction agent may be added to the first electrode layer forming coating solution. When the agent is not added, it is preferably in the range of 400 ° C. to 600 ° C., and particularly preferably in the range of 450 ° C. to 550 ° C. On the other hand, when an oxidizing agent and / or a reducing agent is added to the first electrode layer forming coating solution, k is preferably in the range of 150 ° C. to 600 ° C., and more preferably in the range of 250 ° C. to 400 ° C. It is preferable that In particular, when the first electrode layer made of ITO is formed in this step, the temperature is preferably in the range of 300 ° C. to 500 ° C., and more preferably in the range of 350 ° C. to 450 ° C.

  In this step, examples of such a heating method for heating the porous layer include heating methods such as a hot plate, an oven, a baking furnace, an infrared lamp, and a hot air blower. In particular, a method capable of contacting the first electrode layer forming coating solution while maintaining the temperature of the porous layer at the above temperature is preferable, and specifically, a method of heating from the rear surface side of the heat resistant substrate with a hot plate is preferable.

E. Next, a method for manufacturing an oxide semiconductor electrode according to the present invention will be described. The method for producing an oxide semiconductor electrode of the present invention uses a heat resistant substrate, and a porous layer forming layer forming step of forming a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate, and A metal whose surface is covered with an insulating material on the heat-resistant substrate by having an insulating coating step of coating the surface of the metal oxide semiconductor fine particles contained in the porous layer forming layer with an insulating material A porous layer forming step for forming a porous layer containing oxide semiconductor fine particles, and a first electrode layer for forming a first electrode layer made of a metal oxide on the porous layer by a spray pyrolysis method It has a formation process, a base material adhesion process for adhering a base material on the first electrode layer, and a heat resistant substrate peeling process for peeling the heat resistant substrate from the porous layer. is there.

  Such a method for producing an oxide semiconductor electrode of the present invention will be described with reference to the drawings. FIG. 7 is a schematic view showing an example of a method for producing an oxide semiconductor electrode of the present invention. As illustrated in FIG. 7, the oxide semiconductor electrode manufacturing method of the present invention uses a heat-resistant substrate 1 (FIG. 7A), and forms a porous layer containing metal oxide semiconductor fine particles on the heat-resistant substrate 1. A porous layer forming layer forming step (FIG. 7 (b) -1) for forming the working layer 2 ′, and the surface of the metal oxide semiconductor fine particles contained in the porous layer forming layer 2 ′ A porous layer 2 containing metal oxide semiconductor fine particles whose surface is coated with an insulating material on the heat-resistant substrate 1 by having an insulating coating step (FIG. 7B-2) coated with A porous layer forming step to be formed (FIG. 7B), and a first electrode layer forming step in which a first electrode layer 3 made of a metal oxide is formed on the porous layer 2 by spray pyrolysis. (FIG. 7C), an adhesive layer 5 made of an adhesive resin is formed on the first electrode layer 3. A base material bonding step for bonding the base material 4 (FIG. 7D), and a heat resistant substrate peeling step for peeling the heat resistant substrate 1 from the porous layer 2 (FIG. 7E). The oxide semiconductor electrode 11 ′ having a configuration in which the first electrode layer 3 and the porous layer 2 are laminated in this order on the base material 4 is manufactured (FIG. 7F). .

  According to the present invention, the porous layer forming step includes the porous layer forming layer forming step and the insulating coating step, and includes a metal oxide semiconductor fine particle whose surface is coated with an insulating material. An oxide semiconductor electrode having excellent semiconductor characteristics is manufactured by forming a first electrode layer by spray pyrolysis, wherein the first electrode layer forming step is to form a porous layer. Can do.

The manufacturing method of the oxide semiconductor electrode of the present invention includes at least the porous layer forming step, the first electrode layer forming step, the base material bonding step, and the heat-resistant substrate peeling step, and is necessary. Depending on the, other optional steps may be included.
Hereafter, each process used for this invention is demonstrated in order.

  The porous layer forming step and the first electrode layer forming step used in the present invention are the same as those described in the above section “D. Method for producing oxide semiconductor electrode laminate”. Explanation here is omitted.

1. Substrate bonding step First, the substrate bonding step used in the present invention will be described. This step is a step of bonding the base material on the first electrode layer formed by the first electrode layer forming step.

In this step, the method for adhering the base material on the first electrode layer is not particularly limited as long as it can adhere the base material on the first electrode layer with a desired adhesive force. . Especially in this process, it is preferable to adhere | attach the said 1st electrode layer and the said base material through an contact bonding layer. This is because according to such a method, it is easy to bond the first electrode layer and the base material with a desired adhesive force.
When the first electrode layer and the base material are bonded by such a method, the oxide semiconductor electrode manufactured according to the present invention has an adhesive layer formed between the base material and the first electrode layer. It will have a configuration.

  Here, the base material and the adhesive layer used in this step are the same as those described in the above section “B. Oxide Semiconductor Electrode”, and thus the description thereof is omitted here.

  In this step, as a method of bonding the first electrode layer and the base material via the adhesive layer, the adhesive layer is formed on the base material in advance, and the base material having the adhesive layer is used as the adhesive layer and the first layer. A method in which the electrode layer is disposed so as to adhere, and then heat-sealed; a film made of an adhesive resin; and a method in which the first electrode layer and the substrate are laminated through the film, etc. Can be mentioned.

  The method for forming an adhesive layer made of an adhesive resin on the substrate is not particularly limited. For example, an adhesive layer forming coating solution containing an adhesive resin is applied on the substrate. Can be formed.

2. Next, the heat-resistant substrate peeling process used for this invention is demonstrated. This step is a step of peeling the heat-resistant substrate bonded on the porous layer from the porous layer after the base material bonding step.

  In the heat-resistant substrate peeling step, a method for peeling the heat-resistant substrate from the oxide semiconductor electrode with a heat-resistant substrate is not particularly limited, and a general peeling method can be used. In this step, the heat-resistant substrate can be peeled off by mechanical polishing or chemical removal such as etching.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the technical idea described in the claims of the present invention has substantially the same configuration and exhibits the same function and effect regardless of the case. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described more specifically with reference to examples.

1. Example (1) Production of Layer for Forming Porous Layer Acrylic resin (molecular weight 25000, glass transition temperature 105) of 1% by mass of TiO ₂ fine particles (P25 manufactured by Nippon Aerosil Co., Ltd.) having a primary particle diameter of 20 nm and the main component of which is polymethyl methacrylate ° C: BR87 manufactured by Mitsubishi Rayon Co., Ltd.) An acrylic resin was dissolved in methyl ethyl ketone and toluene using a homogenizer so as to be 10% by mass, and then a coating solution for forming an intervening layer was prepared by dispersing TiO ₂ fine particles. The intervening layer forming layer was formed by applying the intervening layer forming coating solution on a non-alkali glass substrate (thickness 0.7 mm) prepared as a heat-resistant substrate with a wire bar and drying. Next, Solar Nanox Ti Nanoxide D is prepared as a coating liquid for forming an oxide semiconductor layer, and this is applied to a doctor blade (5 mil) on a heat-resistant substrate having an intervening layer forming layer formed only in the predetermined region. Was applied. Next, after standing at room temperature for 20 minutes, an oxide semiconductor layer forming layer was formed by drying at 100 ° C. for 30 minutes. Thereafter, an oxide semiconductor layer forming layer is formed on the intervening layer forming layer by firing in an atmospheric pressure atmosphere at 500 ° C. for 30 minutes using an electric muffle furnace (P90 manufactured by Denken). A porous forming layer was formed.

(2) Coating of insulating material The heat-resistant substrate on which the porous layer was formed was immersed in a 4 mass% ethanol solution of magnesium ethoxide (manufactured by Kanto Chemical Co., Inc.) for 24 hours, washed with ethanol, By baking at 550 ° C. for 60 minutes, the surface of the TiO ₂ fine particles contained in the porous layer was coated with magnesium oxide. The film thickness of the coated magnesium oxide was about 2 nm as observed with an electron transmission microscope (TEM).

(3) Formation of first electrode layer A coating solution for forming a first electrode layer was prepared by dissolving indium chloride 0.1 mol / L and tin chloride 0.005 mol / L in ethanol. The heat-resistant substrate on which the porous layer was formed was placed on a hot plate (400 ° C.) with the porous layer facing upward to heat the porous. Next, the first electrode layer forming coating solution was sprayed on the heated porous layer with an ultrasonic sprayer to form an ITO film as a transparent electrode having a thickness of 500 nm. This obtained the laminated body for oxide semiconductor electrodes.

(4) Adhesion of base material A PET film (Toyobo A5100, thickness 125 μm) was used as an opposing base material, and a heat sealant (Toyobo MD1985) was applied to the surface and air-dried to form an adhesive layer. The base material was bonded to the oxide semiconductor electrode laminate at 120 ° C. so that the adhesive layer was in contact with the first electrode layer.

(5) Peeling of heat-resistant substrate Next, the heat-resistant substrate was physically peeled. Through these steps, an oxide semiconductor electrode was obtained.

(6) Loading of dye sensitizer By dissolving a ruthenium complex (Kojima Chemical Co., Ltd. RuL ₂ (NCS) ₂ ) as a dye sensitizer in an absolute ethanol solution to a concentration of 3 × 10 ⁻⁴ mol / L. A dye solution for adsorption was prepared. Next, the oxide semiconductor electrode was immersed in the dye solution for adsorption, and then dried to support the dye sensitizer in the porous layer.

(7) Production of dye-sensitized solar cell Using methoxyacetonitrile as a solvent, lithium iodide at a concentration of 0.1 mol / L, iodine at a concentration of 0.05 mol / L, dimethylpropylimidazolium iodide at a concentration of 0.3 mol / L A solution in which tertiary butylpyridine having a concentration of 0.5 mol / L was dissolved was used as an electrolyte layer forming coating solution. Next, after the porous layer of the oxide semiconductor electrode is trimmed to 1 cm × 1 cm, the counter electrode base material is bonded with Surlyn having a thickness of 20 μm, and the electrolyte layer forming coating liquid is impregnated therebetween, thereby coloring the dye A sensitized solar cell was produced. As the counter electrode substrate, a substrate having a thickness of 150 nm and having a surface resistance of 7 Ω / □ and a platinum film having a thickness of 50 nm provided by sputtering on an opposing substrate having an ITO sputter layer was used.

(8) Evaluation The evaluation of the produced dye-sensitized solar cell is based on AM1.5, a group having a porous layer on which a dye sensitizer is adsorbed using pseudo-sunlight (incident light intensity of 100 mW / cm ² ) as a light source. Incidence was made from the material side, and current-voltage characteristics were measured by applying voltage with a source measure unit (Caseley 2400 type). As a result, the short-circuit current was 15, ² mA / cm ² , the open-circuit voltage was 730 mV, and the conversion efficiency was 6.8%.

2. Comparative Example A dye-sensitized solar cell was produced in the same manner as in Example 1 except that the coating with the insulating material was not performed. The produced dye-sensitized solar cell was evaluated in the same manner as in Example 1. As a result, the short-circuit current was 14.8 mA / cm ² , the open-circuit voltage was 680 mV, and the conversion efficiency was 5.7%.

It is a schematic sectional drawing which shows an example of the laminated body for oxide semiconductor electrodes of this invention. It is a schematic sectional drawing which shows an example of the oxide semiconductor electrode of this invention. It is a schematic sectional drawing which shows the other example of the oxide semiconductor electrode of this invention. It is a schematic sectional drawing which shows an example of the dye-sensitized solar cell of this invention. It is a schematic sectional drawing which shows the other example of the dye-sensitized solar cell of this invention. It is the schematic which shows an example of the manufacturing method of the laminated body for oxide semiconductor electrodes of this invention. It is the schematic which shows an example of the manufacturing method of the oxide semiconductor electrode of this invention. It is the schematic which shows the example of a general dye-sensitized solar cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Heat-resistant board | substrate 2 ... Porous layer 3 ... 1st electrode layer 4 ... Base material 5 ... Adhesive layer 10 ... Stacked body for oxide semiconductor electrodes 11, 11 '... Oxide semiconductor electrode 20, 20' ... Dye-sensitized type Solar cell 21 ... Counter electrode base material 21a ... Opposing base material 21b ... Second electrode layer 22 ... Electrolyte layer 23 ... Sealing material 24 ... Wiring

Claims (6)

A heat-resistant substrate, a porous layer formed on the heat-resistant substrate and containing metal oxide semiconductor fine particles, and a first electrode layer formed on the porous layer by a spray pyrolysis method and made of a metal oxide. A laminated body for an oxide semiconductor electrode,
A laminate for an oxide semiconductor electrode, wherein the metal oxide semiconductor fine particles are coated with an insulating material on the surface. A base material, a first electrode layer formed on the base material by a spray pyrolysis method and made of a metal oxide, a porous layer formed on the first electrode layer and containing metal oxide semiconductor fine particles, An oxide semiconductor electrode comprising:
An oxide semiconductor electrode characterized in that the metal oxide semiconductor fine particles are coated with an insulating material on the surface.   The oxide semiconductor electrode according to claim 2, wherein an adhesive layer containing an adhesive resin is formed between the base material and the first electrode layer.   The counter electrode substrate comprising the oxide semiconductor electrode according to claim 2 or 3, and a counter substrate, and a second electrode layer formed on the counter substrate and made of a metal oxide, A structure in which a porous layer and the second electrode layer are arranged to face each other, and an electrolyte layer including a redox pair is formed between the oxide semiconductor electrode and the counter electrode substrate. A dye-sensitized solar cell, comprising: Using a heat resistant substrate, a porous layer forming layer forming step for forming a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate, and metal oxidation contained in the porous layer forming layer Forming a porous layer containing metal oxide semiconductor fine particles whose surfaces are coated with an insulating material on the heat-resistant substrate. A porous layer forming step,
And a first electrode layer forming step of forming a first electrode layer made of a metal oxide on the porous layer by a spray pyrolysis method. Using a heat resistant substrate, a porous layer forming layer forming step for forming a porous layer forming layer containing metal oxide semiconductor fine particles on the heat resistant substrate, and metal oxidation contained in the porous layer forming layer Forming a porous layer containing metal oxide semiconductor fine particles whose surfaces are coated with an insulating material on the heat-resistant substrate. A porous layer forming step,
A first electrode layer forming step of forming a first electrode layer made of a metal oxide on the porous layer by spray pyrolysis;
A base material bonding step of bonding a base material on the first electrode layer;
And a heat-resistant substrate peeling step of peeling the heat-resistant substrate from the porous layer.

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