JP5217337B2 - Laminate for oxide semiconductor electrode, oxide semiconductor electrode, dye-sensitized solar cell, method for producing laminate for oxide semiconductor electrode, and method for producing oxide semiconductor electrode - Google Patents

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. Particularly in recent years, there has been a demand for flexibility in dye-sensitized solar cells, which is useful in that a flexible oxide semiconductor electrode can be easily produced using a flexible substrate according to the above transfer method. It is.

  By the way, the oxide semiconductor electrode has a configuration in which a porous layer formed as a porous body by containing metal oxide semiconductor fine particles and a first electrode layer made of a metal oxide are laminated. Since the porous layer and the first electrode layer have different functions, the metal oxide constituting the metal oxide semiconductor fine particles and the metal oxide constituting the first electrode layer are usually different from each other. It is used. For this reason, the oxide semiconductor electrode having the above-described configuration has a problem that adhesion between the first electrode layer and the porous layer is low. In particular, in recent years, it has become possible to form a flexible oxide semiconductor electrode by the transfer method described above. However, the problem of the low adhesion is that the flexible oxide semiconductor electrode is porous when deformed. It is becoming apparent by the phenomenon of peeling at the interface between the quality layer and the first electrode layer.

JP 2002-184475 A

  This invention is made | formed in view of such a problem, and provides the laminated body for oxide semiconductor electrodes excellent in the adhesiveness of a porous layer and a 1st electrode layer, and an oxide semiconductor electrode. This is the main purpose.

  In order to solve the above problems, 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 made of a first metal oxide, and the porous layer. And a first electrode layer made of a second metal oxide, the oxide semiconductor electrode laminate, wherein the first metal oxide and the first electrode layer are interposed between the porous layer and the first electrode layer. A mixed oxide layer containing a second metal oxide is formed, and the porous layer and the first electrode layer are formed in contact with the mixed oxide layer, Provided is a laminate for an oxide semiconductor electrode.

  According to the present invention, the first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer and the second metal oxide constituting the first electrode layer are included in the mixed oxide layer. By including both, the porous layer and the first electrode layer can be firmly bonded via the mixed oxide layer. For this reason, according to this invention, the laminated body for oxide semiconductor electrodes excellent in the adhesiveness of a porous layer and a 1st electrode layer can be obtained.

  In order to solve the above problems, the present invention provides a base material, a first electrode layer formed on the base material and made of a second metal oxide, formed on the first electrode layer, and a first metal. An oxide semiconductor electrode comprising a metal oxide semiconductor fine particle comprising an oxide, wherein the first metal oxide and the first electrode are interposed between the porous layer and the first electrode layer. An oxide characterized in that a mixed oxide layer containing two metal oxides is formed, and the porous layer and the first electrode layer are formed in contact with the mixed oxide layer A semiconductor electrode is provided.

  According to the present invention, the first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer and the second metal oxide constituting the first electrode layer are included in the mixed oxide layer. By including both, the porous layer and the first electrode layer can be firmly bonded via the mixed oxide layer. For this reason, according to this invention, the oxide semiconductor electrode excellent in the adhesiveness of a porous layer and a 1st electrode layer can be obtained.

  In 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 the oxide semiconductor electrode of the present invention can be easily formed by a transfer method.

  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.

  According to the present invention, since the oxide semiconductor electrode of the present invention is used, the dye sensitization is excellent in adhesion between the porous layer and the first electrode layer, and the performance is not easily deteriorated due to deformation or the like. Type solar cell can be obtained.

  Further, the present invention uses a heat resistant substrate, a porous layer forming step of forming a porous layer containing metal oxide semiconductor fine particles made of a first metal oxide on the heat resistant substrate, and on the porous layer, A mixed oxide layer forming step of forming a mixed oxide layer containing the first metal oxide and the second metal oxide; and a first layer made of the second metal oxide on the mixed oxide layer. And a first electrode layer forming step of forming an electrode layer. A method for manufacturing a stacked body for an oxide semiconductor electrode is provided.

  According to the present invention, the mixed oxide layer forming step includes a first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer, and a second metal oxide constituting the first electrode layer. And forming the mixed oxide layer including both of the porous layer and the first electrode layer through the mixed oxide layer. Can be firmly bonded. For this reason, according to this invention, the laminated body for oxide semiconductor electrodes excellent in the adhesiveness of a porous layer and a 1st electrode layer can be manufactured.

  In the present invention, the mixed oxide layer forming step includes a first metal compound having a metal element constituting the first metal oxide and a second metal compound having a metal element constituting the second metal oxide. It is preferable that the mixed oxide layer is formed by a spray pyrolysis method using a mixed oxide layer-forming coating solution. This is because, in the mixed oxide layer forming step, it is possible to form a denser mixed oxide layer having excellent conductivity.

  Furthermore, the present invention uses a heat resistant substrate, a porous layer forming step of forming a porous layer containing metal oxide semiconductor fine particles made of a first metal oxide on the heat resistant substrate, and on the porous layer, A mixed oxide layer forming step of forming a mixed oxide layer containing the first metal oxide and the second metal oxide; and a first layer made of the second metal oxide on the mixed oxide layer. A first electrode layer forming step for forming an electrode layer; a base material bonding step for bonding a base material on the first electrode layer; and a heat resistant substrate peeling step for peeling the heat resistant substrate from the porous layer. An oxide semiconductor electrode manufacturing method is provided.

  According to the present invention, the mixed oxide layer forming step includes a first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer, and a second metal oxide constituting the first electrode layer. In the oxide semiconductor electrode manufactured according to the present invention, the porous layer and the first electrode layer are firmly formed through the mixed oxide layer. It can be glued to. For this reason, according to this invention, the oxide semiconductor electrode excellent in the adhesiveness of a porous layer and a 1st electrode layer can be manufactured.

  In the present invention, the mixed oxide layer forming step includes a first metal compound having a metal element constituting the first metal oxide and a second metal compound having a metal element constituting the second metal oxide. It is preferable that the mixed oxide layer is formed by a spray pyrolysis method using a mixed oxide layer-forming coating solution. This is because, in the mixed oxide layer forming step, it is possible to form a denser mixed oxide layer having excellent conductivity.

  INDUSTRIAL APPLICATION This invention has an effect that the laminated body for oxide semiconductor electrodes excellent in the adhesiveness of a porous layer and a 1st electrode layer, and an oxide semiconductor electrode can be provided.

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 laminate for an oxide semiconductor electrode 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 made of a first metal oxide, and the porous layer. And a first electrode layer made of a second metal oxide, wherein the first metal oxide and the second metal oxide are provided between the porous layer and the first electrode layer. And the porous layer and the first electrode layer are formed in contact with the mixed oxide layer.

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, a stacked body 10 for an oxide semiconductor electrode of the present invention is a porous substrate including a heat-resistant substrate 1 and metal oxide semiconductor fine particles formed on the heat-resistant substrate 1 and made of a first metal oxide. A porous layer 2, a mixed oxide layer 3 formed so as to be in contact with the porous layer 2, and a first electrode layer formed so as to be in contact with the mixed oxide layer 3 and made of a second metal oxide. 4.
In such an example, the laminated body 10 for an oxide semiconductor electrode according to the present invention includes a first metal oxide in which the mixed oxide layer 3 constitutes metal oxide semiconductor fine particles contained in the porous layer 2. And a second metal oxide constituting the first electrode layer 4.

According to the present invention, the first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer and the second metal oxide constituting the first electrode layer are included in the mixed oxide layer. By including both, the porous layer and the first electrode layer can be firmly bonded via the mixed oxide layer.
For this reason, according to this invention, the laminated body for oxide semiconductor electrodes excellent in the adhesiveness of a porous layer and a 1st electrode layer can be obtained.

  In addition, the laminated body for oxide semiconductor electrodes of this invention is used suitably in order to mainly 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, a mixed oxide layer, and a first electrode layer, and may have any other configuration as necessary. It is.
Hereafter, each structure used for the oxide semiconductor electrode of this invention is demonstrated in order.

1. Mixed oxide layer First, the mixed oxide layer used in the present invention will be described. The mixed oxide layer used in the present invention is formed between a porous layer to be described later and a first electrode layer to be described later, and constitutes a first metal oxide constituting metal oxide semiconductor fine particles contained in the porous layer. And a second metal oxide constituting the first electrode layer. The mixed oxide layer used in the present invention has a function of bonding the porous layer and the first electrode layer.

Here, since the porous layer described later contains the metal oxide semiconductor fine particles made of the first metal oxide, the mixed oxide layer used in the present invention contains the first metal oxide. In common with the porous layer, the second layer is different from the porous layer in that it contains the second metal compound and is a dense layer rather than a porous layer. In addition, since the first electrode layer described later is made of the second metal oxide, the mixed oxide layer used in the present invention is common to the first electrode layer in that it contains the second metal oxide. It is different from the first electrode layer in that it contains the first metal oxide.
Hereinafter, such a mixed oxide layer will be described.

(1) 1st metal oxide and 2nd metal oxide The 1st metal oxide used for this invention is a constituent material of the metal oxide semiconductor fine particle contained in the porous layer mentioned later. Therefore, the first metal oxide used in the present invention is inevitably determined by the type of the metal oxide semiconductor fine particles.
In addition, when using what was comprised from 2 or more types of 1st metal oxide as said metal oxide semiconductor fine particle, the 1st metal oxide contained in a porous layer is the 1st which comprises the said metal oxide semiconductor fine particle. What is necessary is just to be at least 1 type in 1 metal oxide.
Here, since the first metal oxide used in the present invention will be described in detail in the section of “2. Porous layer” described later, description thereof is omitted here.

Moreover, the 2nd metal oxide used for this invention is a constituent material of the 1st electrode layer mentioned later. Therefore, the first metal oxide used in the present invention is inevitably determined by the aspect of the first electrode layer.
In addition, when using what was comprised from 2 or more types of 2nd metal oxide as said 1st electrode layer, the 2nd metal oxide contained in a porous layer is the 2nd metal which comprises the said 1st electrode layer. What is necessary is just to be at least 1 type in an oxide.
Here, since the second metal oxide used in the present invention will be described in detail in the section of “3. First electrode layer” described later, description thereof is omitted here.

(2) Mixed oxide layer The mixed oxide layer used in the present invention is not particularly limited as long as it contains the first metal oxide and the second metal oxide. It is preferably formed by a thermal decomposition method. This is because the mixed oxide layer formed by the spray pyrolysis method has high density and excellent conductivity.
Here, the spray pyrolysis method is a first metal compound containing the first metal element constituting the first metal oxide and a second metal element containing the second metal element constituting the second metal oxide. A mixed oxide layer is formed by oxidizing the first metal element and the second metal element on the porous layer by spraying a solution containing the metal compound onto the heated porous layer. Is the method.

Here, the mixed oxide layer used in the present invention is formed by the spray pyrolysis method, for example, between the first electrode layer and the mixed oxide layer and the mixed oxide layer. A region where the physical layer is mixed is formed, or a region where the mixed oxide layer and the porous layer are mixed is formed between the mixed oxide layer and the porous layer. By confirming, it can be specified.
That is, as described above, when the mixed oxide layer is formed on the porous layer by the spray pyrolysis method, it is inevitable that a part of the material constituting the mixed oxide layer penetrates into the porous layer. Thus, a region in which the material constituting the mixed oxide layer and the material constituting the porous layer are mixed is formed in the permeated region. The same applies to the case where the mixed oxide layer is formed on the first electrode layer by spray pyrolysis. Therefore, by confirming the existence of this region, it can be specified that the mixed oxide layer is formed by spray pyrolysis.

  In the present invention, the content ratio of the first metal oxide and the second metal oxide contained in the mixed oxide layer is preferably a porous layer and a first electrode layer in the oxide semiconductor electrode laminate of the present invention. It is not particularly limited as long as it is within a range that can be bonded with the adhesive force of. In particular, in the present invention, the content ratio (first metal oxide / second metal oxide) of the first metal oxide and the second metal oxide contained in the mixed oxide layer is 1/99 to 90 / It is preferably within the range of 10, particularly preferably within the range of 5/95 to 75/25, and more preferably within the range of 20/80 to 60/40. This is because if the content ratio is larger than the above range, the adhesion between the mixed oxide layer and the first electrode layer may be insufficient. Moreover, it is because there exists a possibility that the adhesiveness of a mixed oxide layer and a porous layer may become inadequate, and electroconductivity may be impaired when smaller than the said range.

  The aspect in which the first metal oxide and the second metal oxide are included in the mixed oxide layer used in the present invention may be an aspect in which both metal oxides are uniformly distributed in the mixed oxide layer. Alternatively, the mixed oxide layer may have a distribution in the content ratio of both metal oxides. As an aspect in which the content ratio of both metal oxides is distributed in the mixed oxide layer, the adhesion between the porous layer and the first electrode layer may be increased depending on the use of the oxide semiconductor electrode laminate of the present invention. The embodiment is not particularly limited as long as it can be achieved to a desired level. As such an embodiment, for example, the content ratio of the first metal oxide is high in the vicinity of the interface between the mixed oxide layer and the porous layer, and the second metal oxide is in the vicinity of the interface with the first electrode layer. An aspect with a high content ratio can be illustrated.

  Moreover, as thickness of the mixed oxide layer used for this invention, according to the kind etc. of said 1st metal oxide and 2nd metal oxide, a porous layer and a 1st electrode layer are made into desired adhesive force. It is not particularly limited as long as it is within the range where it can be adhered, but in particular, it is preferably in the range of 1 nm to 1000 nm, particularly preferably in the range of 5 nm to 500 nm, and more preferably in the range of 10 nm to 200 nm. It is preferable to be within the range.

2. Next, the porous layer used in the present invention will be described. The porous layer used in the present invention is formed so as to be in contact with the mixed oxide layer, and contains metal oxide semiconductor fine particles made of the first metal oxide. In addition, 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.
Hereinafter, such a porous layer will be described in detail.

(1) Metal Oxide Semiconductor Fine Particle The metal oxide semiconductor fine particle used in the present invention is not particularly limited as long as it is composed of the first metal oxide having semiconductor characteristics, and the oxide semiconductor of the present invention. It can be appropriately selected and used depending on the application of the electrode laminate. As the first metal oxide constituting the metal oxide semiconductor fine particles used in the present invention, for _{example, 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 composed of these first metal oxides are suitable for forming a porous porous layer, and are suitable for the present invention because energy conversion efficiency can be improved and costs can be reduced. Used for.

The metal oxide semiconductor fine particles used in the present invention may be all made of the same first metal oxide, or two or more kinds of different first metal oxides 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.
In addition, since the light scattering effect in the porous layer can be enhanced by using the metal oxide semiconductor fine particles having different particle diameters together, for example, the dye-sensitized type using the oxide semiconductor electrode laminate of the present invention. When a solar cell is produced, there is an advantage that light absorption by the dye sensitizer can be performed efficiently.

  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.

(2) Arbitrary component The porous layer used in the present invention may contain an optional component in addition to the metal oxide semiconductor fine particles. 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 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.

(3) Porous layer The thickness of the porous layer used in the present invention is particularly within the range where 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. It is not limited. In particular, the thickness of the porous layer in the present invention is usually preferably in the range of 1 μm to 100 μm, and 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.

3. First Electrode Layer Next, the first electrode layer used in the present invention will be described. The 1st electrode layer used for this invention is formed so that it may contact | connect on the said mixed oxide layer, and consists of a 2nd metal oxide.
Hereinafter, such a first electrode layer will be described.

  The second metal oxide constituting the first electrode layer used in the present invention is not particularly limited as long as it has desired conductivity. Especially, it is preferable that the 2nd metal oxide used for this invention has a sunlight transmittance | 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 the second metal oxide having sunlight transmittance include SnO ₂ , ITO, IZO, and ZnO. In the present invention, any of these second 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.

4). 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 other than the metal used for (1), a metal alloy, or a metal oxide 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). Oxide Semiconductor Electrode Laminate The oxide semiconductor electrode laminate of the present invention uses at least two types of metal oxides, the first metal oxide and the second metal oxide. A combination of the first metal oxide and the second metal oxide used in the invention is a mixed metal that can form a porous layer and a first electrode layer having desired performance and contains both metal oxides. It is not particularly limited as long as it can form an oxide. Among these, combinations (first metal oxide / second metal oxide) of the first metal oxide and the second metal oxide used in the present invention include, for example, TiO ₂ / ITO, TiO ₂ / FTO, and TiO. ₂ / SnO ₂ , TiO ₂ / ZnO, TiO ₂ / AtO, SnO ₂ / ITO, SnO ₂ / FTO, SnO ₂ / ZnO, SnO ₂ / AtO, ZnO / ITO, ZnO / FTO, ZnO / SnO ₂ , and ZnO / AtO etc. can be mentioned.

5. 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.

6). Method for Producing Oxide Semiconductor Electrode Laminate The oxide semiconductor electrode laminate of the present invention can be generally produced using a known method. 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. The oxide semiconductor electrode of the present invention is formed of a base material, a first electrode layer formed on the base material and made of a second metal oxide, and formed on the first electrode layer and made of the first metal oxide. A porous layer containing metal oxide semiconductor fine particles, wherein the first metal oxide and the second metal oxide are contained between the porous layer and the first electrode layer. The mixed oxide layer is formed, and the porous layer and the first electrode layer are formed in contact with the mixed oxide layer.

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 5, a first electrode layer 4 formed on the base material 5 and made of a second metal oxide, and the first electrode layer. A mixed oxide layer 3 formed so as to be in contact with 4, and a porous layer 2 formed so as to be in contact with the mixed oxide layer 3 and containing metal oxide semiconductor fine particles made of a first metal oxide; It is what has.
In such an example, the oxide semiconductor electrode 11 of the present invention includes the first metal oxide in which the mixed oxide layer 3 constitutes the metal oxide semiconductor fine particles contained in the porous layer 2, and the above-mentioned It contains the 2nd metal oxide which comprises the 1st electrode layer 4, It is characterized by the above-mentioned.

  According to the present invention, the first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer and the second metal oxide constituting the first electrode layer are included in the mixed oxide layer. By including both, the porous layer and the first electrode layer can be firmly bonded via the mixed oxide layer. For this reason, according to this invention, the oxide semiconductor electrode excellent in the adhesiveness of a porous layer and a 1st electrode layer can be obtained.

The oxide semiconductor electrode of the present invention has at least a substrate, a first electrode layer, a mixed oxide 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.

  The mixed oxide layer, 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. Since it exists, description here is abbreviate | 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 has an adhesive layer 6 containing an adhesive resin between the base material 5 and the first electrode layer 4. 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, 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 adhesive resin constituting the adhesive layer, but is usually within a range of 5 μm to 300 μm. 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.

In addition, the oxide semiconductor electrode of the present invention uses at least two kinds of metal oxides of the first metal oxide and the second metal oxide, and the first metal oxide used in the present invention. As a combination of the metal oxide and the second metal oxide, a porous layer and a first electrode layer having desired performance can be formed, and a mixed metal oxide containing both metal oxides can be formed. There is no particular limitation as long as it is present. Among these, combinations (first metal oxide / second metal oxide) of the first metal oxide and the second metal oxide used in the present invention include, for example, TiO ₂ / ITO, TiO ₂ / FTO, and TiO. ₂ / SnO ₂ , TiO ₂ / ZnO, TiO ₂ / AtO, SnO ₂ / ITO, SnO ₂ / FTO, SnO ₂ / ZnO, SnO ₂ / AtO, ZnO / ITO, ZnO / FTO, ZnO / SnO ₂ , and ZnO / AtO etc. can be mentioned.

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. Production Method of Oxide Semiconductor Electrode The oxide semiconductor electrode of the present invention can be produced using a generally 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 the porous layer contains 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 6, a first electrode layer 4, a mixed oxide layer 3, a porous layer 2, and an oxide semiconductor electrode 11 ′. By patterning the second electrode layer 21 b of the counter electrode base material 21, a plurality of cells C are formed between the pair of oxide semiconductor electrodes 11 ′ and the counter electrode base material 21. The cell C may be configured to be connected by the wiring 24. 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 the injection is performed by releasing 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 manufacturing method of the laminated body for oxide semiconductor electrodes of this invention uses the heat resistant substrate, and forms the porous layer which forms the porous layer containing the metal oxide semiconductor fine particle which consists of a 1st metal oxide on the said heat resistant substrate. A mixed oxide layer forming step of forming a mixed oxide layer containing the first metal oxide and the second metal oxide on the porous layer; and the mixed oxide layer forming step on the mixed oxide layer. And a first electrode layer forming step of forming a first electrode layer made of a second metal oxide.

  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 of the present invention uses a heat-resistant substrate 1 (FIG. 6A), and a metal oxide composed of a first metal oxide on the heat-resistant substrate 1. A porous layer forming step (FIG. 6B) for forming a porous layer 2 containing physical semiconductor fine particles, and the first metal oxide and the second metal oxide on the porous layer 2 A mixed oxide layer forming step for forming the mixed oxide layer 3 to be contained (FIG. 6C), and the first electrode layer 4 made of the second metal oxide is formed on the mixed oxide layer 3. And a porous layer 2, a mixed oxide layer 3, and a first electrode layer 4 are laminated in this order on the heat-resistant substrate 1. The oxide semiconductor electrode laminate 10 having the above-described configuration is manufactured (FIG. 6E).

  According to the present invention, the mixed oxide layer forming step includes a first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer and a second metal oxide constituting the first electrode layer. And forming the mixed oxide layer including both of the porous layer and the first electrode layer through the mixed oxide layer. Can be firmly bonded. For this reason, according to this invention, the laminated body for oxide semiconductor electrodes excellent in the adhesiveness of a porous layer and a 1st electrode layer can be manufactured.

The manufacturing method of the oxide semiconductor electrode laminate of the present invention includes at least the porous layer forming step, the mixed oxide layer forming step, and the first electrode layer forming step. And may have other optional steps.
Hereafter, each process used for this invention is demonstrated in order.

1. First, the mixed oxide layer forming step used in the present invention will be described. This step is a step of forming a porous layer containing the first metal oxide and the second metal oxide on the porous layer formed by the porous layer forming step described later.

  The method for forming the mixed oxide layer in this step is not particularly limited as long as it is a method capable of forming the mixed oxide layer containing the first metal oxide and the second metal oxide in a desired mode. Instead, they can be appropriately selected and used according to the types of the first metal oxide and the second metal oxide. Examples of such a method include a spray pyrolysis method, a sputtering method, a CVD method, a vapor deposition method, and a sol-gel method. In the present invention, any of these methods can be suitably used, but among them, the spray pyrolysis method is preferably used. Here, the spray pyrolysis method is a first metal compound containing the first metal element constituting the first metal oxide and a second metal element containing the second metal element constituting the second metal oxide. A mixed oxide layer is formed by oxidizing the first metal element and the second metal element on the porous layer by spraying a solution containing the metal compound onto the heated porous layer. Is the method. More specifically, the porous layer is heated to a temperature equal to or higher than the metal oxide film formation temperature, and the mixed oxide layer forming coating solution in which the first metal compound and the second metal compound are dissolved in a solvent. By spraying on the porous layer, or by spraying the solution containing the first metal compound and the solution containing the two metal oxides from separate nozzles, respectively. Thus, a mixed oxide layer is provided on the porous layer.

  Here, the “metal oxide film formation temperature” means that the metal element in the metal compound contained in the mixed oxide layer forming coating liquid can be combined with oxygen to form a metal oxide film. The temperature differs greatly depending on the type of metal ions and the like, the composition of the mixed oxide layer forming coating solution, and the like. Such “metal oxide film formation temperature” can be measured by the following method. That is, a mixed oxide layer forming coating solution in which a desired metal compound is actually dissolved is prepared, and the metal oxide film is formed by contacting the heat resistant substrate with the porous layer while changing the heating temperature. The lowest substrate heating temperature that can be formed is measured. This minimum substrate heating temperature can be set as the “metal oxide film forming temperature” in the spray pyrolysis 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 spray pyrolysis method will be described in detail.

(1) Mixed oxide layer forming coating solution First, the mixed oxide layer forming coating solution used in this step will be described. The mixed oxide layer forming coating solution used in this step contains the first metal compound and the second metal compound, and a solvent, and contains other compounds as necessary.

(First metal compound)
The first metal compound used in this step is capable of forming the first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer by being oxidized on the porous layer. There is no particular limitation. Therefore, the first metal compound used in this step is appropriately selected according to the type of the first metal oxide. Specific examples of the first metal compound used in this step include an alkoxide, an inorganic compound, a complex, and the like that are precursors of a substance constituting the target first metal oxide. In this step, any of the first metal compounds described above can be suitably used.

  In addition, the 1st metal compound used for this process may be only 1 type, or 2 or more types may be sufficient as it.

(Second metal compound)
The second metal compound used in this step is not particularly limited as long as it can form the second metal oxide constituting the first electrode layer by being oxidized on the porous layer. . Therefore, the second metal compound used in this step is appropriately selected according to the type of the second metal oxide. Specific examples of the second metal compound used in this step include tris (acetylacetonato) indium (III), indium (III) 2-ethylhexanoate, tetraethyltin, and 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, dibutyltin oxide (IV), tricyclohexyl Tin (IV) hydroxide etc. can be mentioned

  In addition, the 2nd metal compound used for this process may be only 1 type, or 2 or more types may be sufficient as it.

(solvent)
The solvent used in the mixed oxide layer forming coating solution is not particularly limited as long as it can dissolve the first metal compound and the second metal compound at a desired concentration. As such a solvent, for example, when a metal salt is used as the first metal compound and the second metal compound, a lower alcohol having a total carbon number of 5 or less, such as water, methanol, ethanol, isopropyl alcohol, propanol, and butanol. , Toluene, and mixed solvents thereof. On the other hand, when using a metal complex as said 1st metal compound and 2nd metal compound, the lower alcohol mentioned above, toluene, and these mixed solvents can be mentioned.

(Additive)
The mixed oxide layer forming coating solution used in this step may contain any additive in addition to the first metal compound and the second metal compound. 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 first metal compound and the second metal compound, and is included in the coating solution for forming a mixed oxide layer. Thus, it has a function of making it possible to create an environment in which a mixed oxide layer can be easily formed in this step.

  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 and the like. The first metal compound and the second metal compound can be appropriately selected and used depending on the type of the first metal compound and the second metal compound. 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, generating hydroxide ions by water electrolysis, and raising the pH of the coating solution for forming a mixed oxide layer. By including such a reducing agent in the mixed oxide layer forming coating solution, it is possible to create an environment in which a mixed oxide layer can be easily formed in this step.

  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, hydroxylation. A sodium boron etc. can be mentioned. Among these, in this step, it is preferable to use a borane complex.

  The mixed oxide layer forming coating solution used in this step 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 mixed oxide layer forming coating solution to make it easy to form a mixed oxide layer. It is what you have. 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 mixed oxide layer forming coating solution and the porous layer, and has a function of facilitating formation of the mixed oxide 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 of Contacting Mixed Oxide Layer Forming Coating Liquid and Porous Layer Next, a method of bringing the mixed oxide layer forming coating liquid and the porous layer into contact in this step will be described. In this step, the mixed oxide layer forming coating solution and the porous layer are brought into contact with each other by a method in which the mixed oxide layer forming coating solution can be uniformly contacted on the porous layer. The method is not particularly limited as long as it is a method that does not lower the temperature of the heated porous layer when the mixed oxide layer forming coating solution and the porous layer are in contact with each other. Is preferred. This is because if the temperature of the porous layer is lowered, a desired mixed oxide layer may not be obtained.

  In this step, the mixed oxide 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 “film formation temperature” varies greatly depending on the types of the first metal compound and the second metal compound, the composition of the coating solution for forming the mixed oxide layer, and the like. Therefore, the “metal oxide film forming temperature” in this step may be determined as appropriate depending on the types of the first metal compound and the second metal compound. For example, a mixed oxide layer forming coating solution may be used. When an oxidizing agent and / or a reducing agent is not added, it is preferably within a range of 400 ° C to 600 ° C, and more preferably within a range of 450 ° C to 550 ° C. On the other hand, when an oxidizing agent and / or a reducing agent is added to the mixed oxide layer forming coating solution, it is preferably within a range of 150 ° C. to 600 ° C., and more preferably within a range of 250 ° C. to 400 ° C. Is preferred.

  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 in which the temperature of the porous layer can be brought into contact with the coating solution for forming a mixed oxide layer while maintaining 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.

2. Next, the porous layer forming step used in the present invention will be described. This step is a step of forming a porous layer containing metal oxide semiconductor fine particles made of the first metal oxide on the heat resistant substrate using a heat resistant substrate.

In this step, a method for forming a porous layer on a heat-resistant substrate is a method that can form a porous layer containing metal oxide semiconductor fine particles made of a predetermined first metal oxide and having a desired porosity. There is no particular limitation. In particular, in this step, a porous layer forming layer is formed by using a heat resistant substrate and forming a porous layer forming layer containing metal oxide semiconductor fine particles made of the first metal oxide and a resin on the heat resistant substrate. The porous layer is preferably formed by the step and the firing step of firing the porous layer forming layer. This is because such a method makes it easy to form a porous layer having an arbitrary porosity.
Hereinafter, a method for forming the porous layer by such a method will be described in detail.

(1) Layer forming process for forming a porous layer First, the layer forming process for forming a porous layer will be described. This step is a step of forming a porous layer forming layer containing metal oxide semiconductor fine particles and a resin on the heat resistant substrate using a heat resistant substrate.

a. Heat-resistant substrate The heat-resistant substrate used in this step is not particularly limited as long as it has heat resistance against the firing temperature in the firing step 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”, and therefore, the description thereof 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 in the baking step described later. . 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.

(2) Firing step Next, the firing step will be described. This step is a step of forming a porous layer which is a porous body by firing the porous layer forming layer formed by the porous layer forming step.

  The method for firing the porous layer forming layer in this step is not particularly limited as long as it can be uniformly fired without uneven heating, 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.

(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.

3. 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 the first electrode layer made of the second metal oxide on the mixed oxide layer formed by the mixed oxide layer forming step.

  The method for forming the first electrode layer in this step is not particularly limited as long as it is a method capable of forming the first electrode layer having a uniform thickness and excellent flatness, and generally a method for forming a metal oxide film. A known method can be used. As a specific example of the method for forming the first electrode layer, a method described in JP-A-2005-166648 can be suitably used.

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 step of forming a porous layer containing metal oxide semiconductor fine particles made of a first metal oxide on the heat resistant substrate, A mixed oxide layer forming step of forming a mixed oxide layer containing the first metal oxide and the second metal oxide on the porous layer; and a second metal on the mixed oxide layer. A first electrode layer forming step for forming a first electrode layer made of an oxide; a base material bonding step for bonding a base material on the first electrode layer; and a heat resistant substrate for peeling the heat resistant substrate from the porous layer. And a peeling step.

  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 metal oxide semiconductor fine particles made of a first metal oxide on the heat-resistant substrate 1. A porous layer forming step (FIG. 7B) for forming the porous layer 2 containing, and a mixture containing the first metal oxide and the second metal oxide on the porous layer 2 A mixed oxide layer forming step for forming the oxide layer 3 (FIG. 7C) and a first electrode layer for forming the first electrode layer 4 made of the second metal oxide on the mixed oxide layer 3 A forming step (FIG. 7D), a base material bonding step of bonding the base material 5 on the first electrode layer 4 via an adhesive layer 6 containing an adhesive resin (FIG. 7E), the above A heat-resistant substrate peeling step (FIG. 7 (f)) for peeling the heat-resistant substrate 1 from the porous layer 2, and the adhesive layer 6 and the first electrode layer on the substrate 5. When a mixed oxide layer 3, in which the porous layer 2 is manufactured an oxide semiconductor electrode 11 'having the configuration drafted in this order (FIG. 7 (g)).

  According to the present invention, the mixed oxide layer forming step includes a first metal oxide constituting the metal oxide semiconductor fine particles contained in the porous layer and a second metal oxide constituting the first electrode layer. In the oxide semiconductor electrode manufactured according to the present invention, the porous layer and the first electrode layer are firmly formed through the mixed oxide layer. It can be glued to. For this reason, according to this invention, the oxide semiconductor electrode excellent in the adhesiveness of a porous layer and a 1st electrode layer can be manufactured.

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

  The porous layer forming step, the mixed oxide layer forming step, and the first electrode layer forming step used in the present invention are described in the section “D. Method for producing oxide semiconductor electrode laminate”. Since it is the same as that of what was demonstrated, description here is abbreviate | 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 having 1% by mass of TiO ₂ fine particles having a primary particle diameter of 20 nm (P25 manufactured by Nippon Aerosil Co., Ltd.) as a coating solution for forming an intervening layer, and the main component of which is polymethyl methacrylate (Molecular weight 25000, glass transition temperature 105 ° 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 TiO ₂ fine particles were dispersed to disperse the intervening layer. A forming coating solution was prepared. The coating liquid was coated on a soda-lime glass prepared as a heat-resistant substrate with a wire bar and dried.
Next, Ti Nanoxide D manufactured by Solaronix SA was prepared as a coating liquid for forming an oxide semiconductor layer, and applied on the release layer forming layer with a doctor blade (5 mil). After leaving at room temperature for 20 minutes, it was dried at 100 ° C. for 30 minutes.
Thereafter, it was baked in an atmospheric atmosphere at 500 ° C. for 30 minutes using an electric muffle furnace (P90 manufactured by Denken). This formed the porous layer which has the structure by which the intervening layer and the oxide semiconductor layer were laminated | stacked.

(2) Formation of mixed oxide layer Next, 0.1 mol / L of indium chloride, 0.005 mol / L of tin chloride, and 0.1 mol / L of titanium acetylacetonate are dissolved in ethanol on the porous layer. A mixed oxide layer forming coating solution was prepared. The heat-resistant substrate on which the porous layer is formed is placed on a hot plate (400 ° C.) with the porous layer facing upward to heat the porous layer, and the mixed oxidation is performed on the heated porous layer. The material layer forming coating solution was sprayed by an ultrasonic sprayer to form a mixed oxide layer having a thickness of 100 nm, which was a transparent electrode.

(3) Formation of first electrode layer Next, a coating solution for forming a first electrode layer in which 0.1 mol / L of indium chloride and 0.005 mol / L of tin chloride are dissolved in ethanol is prepared. On the mixed oxide layer, the above solution was sprayed by an ultrasonic sprayer to form a first electrode layer made of ITO having a thickness of 500 nm. Thereby, a transfer body for forming an oxide semiconductor electrode was obtained.

(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 Adsorbed by dissolving ruthenium complex (Kojima Chemical Co., Ltd. RuL2 (NCS) 2) as a dye sensitizer in an absolute ethanol solution to a concentration of 3 × 10 ⁻⁴ mol / L A dye solution 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 Evaluation of the produced dye-sensitized solar cell is based on AM1.5 and pseudo-sunlight (incident light intensity: 100 mW / cm ² ) as a light source from the base material side having the oxide semiconductor layer adsorbed with the dye. The current and voltage characteristics were measured by applying voltage with a source measure unit (Caseley 2400 type). As a result, the short-circuit current was 14, 5 mA / cm ² , the open-circuit voltage was 710 mV, and the conversion efficiency was 6.8%. In addition, in order to evaluate the adhesion, a bending test was performed 100 times with a φ8 mm mandrel tester, but there was no change in the aforementioned element performance.

2. Comparative Example A dye-sensitized solar cell was prepared in the same manner as in Example 1 except that the mixed oxide layer was not formed.
Evaluation of the produced dye-sensitized solar cell was conducted by using AM1.5, pseudo-sunlight (incident light intensity of 100 mW / cm ² ) as a light source, incident from the substrate side having the oxide semiconductor layer adsorbed with the dye, The current-voltage characteristics were measured by applying voltage with a major unit (Caseley 2400 type). As a result, the short-circuit current was 13, 8 mA / cm ² , the open-circuit voltage was 700 mV, and the conversion efficiency was 6.0%. Further, in order to evaluate adhesion, a bending test was performed 100 times with a φ8 mm mandrel tester. As a result, the element performance was remarkably deteriorated due to peeling of the porous layer from the first electrode layer, and the short-circuit current was 1.8 mA / cm. ^{2. The} open circuit voltage was 120 mV, and the conversion efficiency was 0.1%.

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 ... Mixed oxide layer 4 ... 1st electrode layer 5 ... Base material 6 ... Adhesion layer 10 ... Oxide semiconductor electrode laminated body 11,11 '... Oxide semiconductor electrode 20,20 '... Dye-sensitized solar cell 21 ... Counter electrode substrate 21a ... Counter substrate 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 including metal oxide semiconductor fine particles made of a first metal oxide, and a first electrode formed on the porous layer and made of a second metal oxide An oxide semiconductor electrode laminate having a layer,
A mixed oxide layer composed of a single layer containing the first metal oxide and the second metal oxide is formed between the porous layer and the first electrode layer,
The mixed oxide layer is a dense layer;
The porous layer and the first electrode layer are formed so as to be in contact with the mixed oxide layer,
The mixed oxide layer has a high content ratio of the first metal oxide in the vicinity of the interface on the mixed oxide layer side with the porous layer, and on the mixed oxide layer side with the first electrode layer . A laminated body for an oxide semiconductor electrode, wherein the content ratio of the second metal oxide is high in the vicinity of the interface. A porous material comprising a base material, a first electrode layer formed on the base material and made of a second metal oxide, and metal oxide semiconductor fine particles formed on the first electrode layer and made of the first metal oxide An oxide semiconductor electrode comprising:
A mixed oxide layer composed of a single layer containing the first metal oxide and the second metal oxide is formed between the porous layer and the first electrode layer,
The mixed oxide layer is a dense layer;
The porous layer and the first electrode layer are formed so as to be in contact with the mixed oxide layer,
The mixed oxide layer has a high content ratio of the first metal oxide in the vicinity of the interface on the mixed oxide layer side with the porous layer, and on the mixed oxide layer side with the first electrode layer . An oxide semiconductor electrode, wherein the content ratio of the second metal oxide is high in the vicinity of the interface.   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, and forming a porous layer containing metal oxide semiconductor fine particles composed of a first metal oxide on the heat-resistant substrate; and
A mixed oxide layer forming step of forming a mixed oxide layer composed of a single layer containing the first metal oxide and the second metal oxide on the porous layer;
A first electrode layer forming step of forming a first electrode layer made of the second metal oxide on the mixed oxide layer, and a method of manufacturing a stacked body for an oxide semiconductor electrode,
The mixed oxide layer forming step includes a first metal compound having a metal element constituting the first metal oxide and a second metal compound having a metal element constituting the second metal oxide. a mixed oxide layer forming coating solution, high content ratio of the first metal oxide in the vicinity of the interface of the mixed oxide layer side of the porous layer of the mixed oxide layer, and the second A dense mixed oxide layer is formed by spray pyrolysis so that the content ratio of the second metal oxide is high in the vicinity of the interface on the mixed oxide layer side with one electrode layer. The manufacturing method of the laminated body for oxide semiconductor electrodes made into. Using a heat-resistant substrate, and forming a porous layer containing metal oxide semiconductor fine particles composed of a first metal oxide on the heat-resistant substrate; and
A mixed oxide layer forming step of forming a mixed oxide layer composed of a single layer containing the first metal oxide and the second metal oxide on the porous layer;
A first electrode layer forming step of forming a first electrode layer made of the second metal oxide on the mixed oxide layer;
A base material bonding step of bonding a base material on the first electrode layer;
A heat-resistant substrate peeling step of peeling the heat-resistant substrate from the porous layer, and a method for producing an oxide semiconductor electrode,
The mixed oxide layer forming step includes a first metal compound having a metal element constituting the first metal oxide and a second metal compound having a metal element constituting the second metal oxide. a mixed oxide layer forming coating solution, high content ratio of the first metal oxide in the vicinity of the interface of the mixed oxide layer side of the porous layer of the mixed oxide layer, and the second A dense mixed oxide layer is formed by spray pyrolysis so that the content ratio of the second metal oxide is high in the vicinity of the interface on the mixed oxide layer side with one electrode layer. A method for producing an oxide semiconductor electrode.

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