JP5841853B2 - Conductive laminate and organic thin solar cell element - Google Patents

Description

  The present invention relates to a conductive laminate and an organic photoelectric conversion element having the conductive laminate.

Organic devices such as organic photoelectric conversion elements, organic EL elements, touch panels, displays, and organic transistor electrodes are examples of products for which applications of organic conductive materials are expected. Among these organic devices, organic photoelectric conversion elements typified by organic solar cells are one of the leading candidates for energy sources to solve energy problems that are global problems, and have a low environmental impact. Since there are many requests for the use of solar energy supplied semi-permanently, it is actively researched. Organic solar cells, which are organic photoelectric conversion elements, are capable of producing lightweight, inexpensive, and flexible elements, and are the next generation solar cells that can replace solar cells using inorganic materials such as silicon semiconductors, which are currently mainstream. Expected.
Against this background, research on organic photoelectric conversion elements using organic conductive materials has been conducted worldwide, and organic photoelectric conversion that can improve the photoelectric conversion efficiency of organic photoelectric conversion elements, in particular, the short-circuit current density. The design technology of the element structure is important.

  In general, an organic device has, for example, a photoelectric conversion layer in the case of an organic photoelectric conversion element and an organic light emitting layer in the case of an organic EL element, between an anode electrode and a cathode electrode. In addition, various organic thin film layers may be provided between the photoelectric conversion layer or the organic light emitting layer and the electrode for the purpose of reducing the contact resistance between the photoelectric conversion layer or the organic light emitting layer and the electrode.

  For example, such an organic thin film layer is known to be formed using a dispersion obtained by dissolving PEDOT (poly (3,4- (ethylenedioxy) thiophene)) and PSS (polystyrene sulfonic acid) in water. It has been. As a method of forming the organic thin film layer, the dispersion is applied onto the anode electrode substrate, a coating film is formed, and the colloidal particles composed of PEDOT and PSS are formed by removing the solvent in the coating film by heating and drying. An organic thin film layer containing can be formed.

However, the organic thin film layer containing colloidal particles composed of PEDOT and PSS has a problem that the surface resistance increases because the film surface and the layer interface are not smooth.
For example, Patent Document 1 describes an invention relating to a method for forming an organic thin film layer in an organic device such as an organic EL element. Patent Document 1 proposes to use a solution obtained by centrifuging a dispersion containing PEDOT and PSS at a rotation speed of 3000 rpm or more for the purpose of solving the above-described problem.
Patent Document 2 describes an invention related to an organic layer forming coating solution for forming an organic layer of an LED display by an ink jet method, and a high-boiling organic solvent is blended in the coating solution. Thus, there is a disclosure that the surface shape of the organic layer can be flattened.

JP 2010-205485 A JP 2001-52861 A

  However, although the organic thin film layer formed by the method described in Patent Documents 1 and 2 is used in organic EL elements and LED displays, the surface resistance is such that it can contribute to the improvement of the short-circuit current density of the organic photoelectric conversion element. It cannot be said that the rate and the surface roughness are suppressed. Therefore, there is a demand for a conductive laminate that can contribute to an improvement in short-circuit current density even when applied to an organic photoelectric conversion element.

  The present invention provides a conductive laminate and an organic photoelectric conversion element that have small surface roughness, excellent smoothness, low surface resistance, and can improve the short-circuit current density when applied to an organic photoelectric conversion element. For the purpose.

The present inventors have found that a conductive laminate in which a buffer layer and a coating layer made of a material having a specific surface resistance are provided on a substrate can solve the above problems, and have completed the present invention. .
That is, the present invention provides the following [1] to [7].
[1] A conductive laminate having, on a substrate, a buffer layer having a thickness of 10 to 1000 nm and a coating layer having a thickness of 1 to 50 nm in order,
The surface resistivity of the single layer consisting only of the buffer layer is 1000 Ω / □ or less, and the surface resistivity of the single layer consisting only of the coating layer is 10 ⁵ to 10 ¹⁰ Ω / □,
The arithmetic average roughness (Ra) of the coating layer is 3.00 nm or less, and the surface resistivity of the conductive laminate measured from the exposed coating layer side of the conductive laminate is 500 Ω / □ or less. A conductive laminate.
[2] The conductive laminate according to the above [1], wherein the material forming the buffer layer includes a water-based conductive polymer.
[3] The conductive laminate according to the above [1] or [2], wherein the material forming the coating layer includes a curable conductive polymer that is soluble in an organic solvent and insoluble in water.
[4] The conductivity according to any one of [1] to [3], wherein the ratio of the thickness of the coating layer to the buffer layer [coating layer / buffer layer] is 1/99 to 50/50. Laminated body.
[5] The conductive laminate according to any one of [1] to [4], wherein the substrate is a substrate with an electrode.
[6] An organic photoelectric conversion element having the conductive laminate according to any one of [1] to [5].

  The conductive laminate of the present invention has small surface roughness, excellent smoothness, low surface resistivity, and can improve the short-circuit current density when applied to an organic photoelectric conversion element.

It is sectional drawing of the electroconductive laminated body which shows the one aspect | mode of the electroconductive laminated body of this invention. It is sectional drawing of the organic photoelectric conversion element which shows the 1st aspect of the organic photoelectric conversion element of this invention. It is sectional drawing of the organic photoelectric conversion element which shows the 2nd aspect of the organic photoelectric conversion element of this invention.

[Conductive laminate]
FIG. 1 is a cross-sectional view of a conductive laminate showing one embodiment of the conductive laminate of the present invention.
As shown in FIG. 1, the conductive laminate 1 of the present invention has a buffer layer 12 having a thickness of 10 to 1000 nm and a coating layer 13 having a thickness of 1 to 50 nm on a substrate 11 in this order. In addition, the conductive laminated body of this invention may have layers other than the above in the range which does not impair an effect.

In the conductive laminate 1 of the present invention, the surface resistivity of a single layer consisting only of the buffer layer 12 is 1000 Ω / □ or less, and the surface resistivity of a single layer consisting only of the coating layer 13 is 10 ⁵ to 10 ¹⁰ Ω / □. is there.
That is, the conductive laminate of the present invention is provided with a buffer layer having a low surface resistivity and a thickness of 10 to 1000 nm on the substrate, and a coating layer having a high surface resistivity and a thickness of 1 to 50 nm on the substrate. Have a configuration.
By having such a configuration, the surface roughness of the conductive laminate can be reduced and the smoothness of the surface of the conductive laminate can be improved as compared to the case where only the buffer layer or the coating layer is laminated. To do. Further, the surface resistivity of the conductive laminate measured from the exposed coating layer side of the conductive laminate (hereinafter also simply referred to as “surface resistivity of the conductive laminate”) is composed of only the buffer layer. It can be reduced as compared with the case of a single layer.
That is, by improving the smoothness of the surface of the conductive laminate, the leakage current between the electrodes decreases, and at the same time the surface resistivity of the conductive laminate decreases. When applied to an element, it is considered that the short circuit current density of the organic photoelectric conversion element is improved.

On the other hand, in the case of a conductive laminate in which only a layer formed from a material having a low surface resistivity is laminated on a substrate, the surface roughness of the formed layer tends to be relatively large. As a result, when the leakage current between the electrodes cannot be suppressed and the surface resistivity of the conductive laminate cannot be sufficiently reduced, the conductive laminate is applied to an organic photoelectric conversion element. Further, it is considered that the short circuit current density of the organic photoelectric conversion element cannot be sufficiently improved.
In addition, when the conductive laminate has only a layer formed of a material having a high surface resistivity on the substrate, the formed layer tends to have a relatively small surface roughness. The high rate is a problem. Therefore, even if the conductive laminate is applied to an organic photoelectric conversion element, the short-circuit current density of the organic photoelectric conversion element is considered to decrease.

  In the present invention, the surface resistivity of the conductive laminate shows a value different from the surface resistivity of a single layer having only a coating layer. Because the thickness of the buffer layer and the coating layer is several nanometers as described above, even when the coating layer is measured, the characteristics of the buffer layer also affect the surface resistivity value. Compared to the surface resistivity of the material, it is significantly reduced. Although the reason is not clear, by providing the coating layer, the surface resistivity of the conductive laminate can be significantly reduced as compared to the value of the surface resistivity of a single layer of only the buffer layer. .

Hereinafter, the substrate 11, the buffer layer 12, and the coating layer 13 that constitute the conductive laminate 1 of the present invention will be described.
[substrate]
The substrate used in the present invention is appropriately selected according to the use of the conductive laminate. For example, inorganic materials containing glass such as alkali-free glass, quartz glass, borosilicate glass, polyester, polycarbonate, polyolefin, polyamide Examples thereof include films and plates selected from organic materials such as polyimide, polyphenylene sulfide, polyparaxylene, epoxy resin, and fluorine resin, and produced by an arbitrary method. As a board | substrate used by this invention, it is preferable that it is a transparent substrate from a viewpoint which applies an electroconductive laminated body to an organic photoelectric conversion element.

Moreover, as a board | substrate used by this invention, from a viewpoint which applies a conductive laminated body to an organic photoelectric conversion element, the board | substrate with an electrode in which the electrode was formed in said inorganic material, the film produced from an organic material, etc. A substrate made of only electrodes may be used.
Examples of the electrode material to be formed include tin-doped indium oxide (ITO), IrO ₂ , In ₂ O ₃ , SnO ₂ , indium oxide-zinc oxide (IZO), ZnO (Ga, Al-doped), and MoO _3. Can be mentioned. Among these, ITO is preferable from the viewpoints of transparency and conductivity. In addition, although formation of an electrode is normally performed by dry methods, such as sputtering and vapor deposition, wet methods, such as a dip coat method and a spin coat method, may be sufficient and it is not limited.
The thickness of the substrate 11 is not particularly limited, but is usually 0.1 to 10 mm.
The visible light transmittance at a wavelength of 550 nm of the substrate 11 is preferably 80% or more, more preferably 85% or more, and still more preferably 90% or more from the viewpoint of applying the conductive laminate to an organic photoelectric conversion element.

[Buffer layer]
The surface resistivity of the single layer consisting only of the buffer layer in the conductive laminate of the present invention is 1000Ω / □ or less, preferably 850Ω / □ or less, more preferably 700Ω / □ or less, and even more preferably 550Ω / □ or less. is there. When the surface resistivity exceeds 1000 Ω / □, the surface resistivity of the entire conductive laminate is increased, which is not preferable because the short-circuit current density is reduced when applied to an organic photoelectric conversion element.
The “surface resistivity of a single layer consisting only of the buffer layer” means the surface resistivity of the buffer layer of the test sample in a test sample in which only the buffer layer is laminated on the substrate, and the buffer of the test sample. The thickness of the layer is the same as the thickness of the coating layer of the target conductive laminate.
Moreover, the value of surface resistivity is a value measured based on the four probe method prescribed | regulated by JISK7194, More specifically, the value measured by the method as described in an Example is meant.

In the present invention, the material used for forming the buffer layer (hereinafter also referred to as “buffer layer forming material”) may be any material that can be adjusted so that the surface resistivity value of the formed buffer layer falls within the above range. There are no restrictions on the structure and type of the compound of the material.
However, it is preferable that a water-based conductive polymer is included as the buffer layer forming material. In the present invention, the water-based conductive polymer means a water-soluble conductive polymer or a water-dispersible conductive polymer. By including the water-based conductive polymer, it is easy to adjust the surface resistivity of the formed buffer layer so as to belong to the above range. The aqueous conductive polymer used in the present invention is hydrophilic and can be a water dispersion as colloidal particles, and the surface resistivity satisfies the above range.

Examples of such a water-based conductive polymer include polythiophene or doped polythiophene, polypyrrole or doped polypyrrole, polyaniline or doped polyaniline, polyacetylenes, and the like.
Among these, polythiophene, doped polythiophene, polyaniline, or doped polyaniline are preferable from the viewpoints of excellent dispersibility, easy formation of a coating film, high transparency, and excellent conductivity.
Examples of the doped polythiophene include poly (3,4) -ethylenedioxythiophene / polystyrene sulfonate (PEDOT / PSS).
Examples of the doped polyaniline include polyaniline / camphorsulfonic acid (PANI / CSA).
Specific examples of commercially available products include aqueous dispersions of polythiophene such as “HBS5” manufactured by Agfa Materials, Inc., “EL-P3040” manufactured by AGFA, and aqueous dispersions of polyaniline such as ORMECOND1033W manufactured by Nissan Chemical Industries, Ltd. Is mentioned.

  The content of the aqueous conductive polymer is preferably 70 to 100% by mass, more preferably 85 to 100% by mass, further preferably 95 to 100% by mass, and still more preferably substantially 100% by mass in the buffer layer forming material. is there.

  The buffer layer is obtained by dissolving the above buffer layer forming material in water to form an aqueous dispersion, and coating the aqueous dispersion on a substrate by a known coating method such as a spin coating method to form a coating film. Can be formed by heat drying.

  The buffer layer 12 has a thickness of 10 to 1000 nm, preferably 30 to 700 nm, more preferably 50 to 500 nm, and still more preferably 70 to 250 nm. If it is 10 nm or more, it is preferable for maintaining the uniformity of the buffer layer, and if it is 1000 nm or less, it is preferable because the light transmittance can be kept high.

[Coating layer]
The surface resistivity of the single layer consisting only of the coating layer in the conductive laminate of the present invention is 10 ⁵ to 10 ¹⁰ Ω / □, preferably 10 ⁶ to 10 ¹⁰ Ω / □, more preferably 10 ⁷ to 10 ^10. Ω / □, more preferably 10 ⁸ to 10 ¹⁰ Ω / □.
If the surface resistivity is within the above range, when a coating layer is formed on the buffer layer, the surface resistivity of the conductive laminate is made lower than the surface resistivity of a single layer consisting only of the buffer layer. Can do. As a result, when applied to an organic photoelectric conversion element, the short-circuit current density can be sufficiently improved.
“Surface resistivity of a single layer consisting only of the coating layer” means the surface resistivity of the coating layer of the test sample in a test sample in which only the coating layer is laminated without forming a buffer layer on the substrate. And the thickness of the coating layer of the said test sample is the same as the thickness of the coating layer which the electroconductive laminated body made into object has.

In the present invention, the material used for forming the coating layer (hereinafter also referred to as “coating layer forming material”) is a material that can be adjusted so that the surface resistivity value of the coating layer to be formed belongs to the above range, And what is necessary is just a thing soluble in an organic solvent, and insoluble in water, and there is no restriction | limiting in the structure of a compound of a material, a kind, etc.
However, the coating layer forming material preferably contains a curable conductive polymer that is soluble in an organic solvent and insoluble in water. Examples of the curable conductive polymer include a thermosetting conductive polymer and an ultraviolet curable conductive polymer.
By including such a curable conductive polymer as the coating layer forming material, it becomes easy to adjust the surface resistivity of the coating layer to be formed so as to belong to the above range.
Further, by containing a curable conductive polymer that is soluble in an organic solvent and insoluble in water as a coating layer forming material, the buffer layer is prevented from being dissolved when the coating layer is formed on the buffer layer. And the surface roughness of the obtained conductive laminate can be reduced. As a result, when applied to an organic photoelectric conversion element, the leakage current between the electrodes decreases, so that the short-circuit current density can be effectively improved.

Examples of the thermosetting conductive polymer include a conductive polymer obtained by modifying a conductive polymer that is soluble in an organic solvent such as polythiophene, polypyrrole, polyaniline, and insoluble in water.
Examples of the ultraviolet curable conductive polymer include polymerizable unsaturated groups such as vinyl groups and (meth) acryloyl groups on the side chains of conductive polymers that are soluble in organic solvents such as polythiophene, polypyrrole, and polyaniline and are insoluble in water. Examples thereof include a conductive polymer having a group. This UV curable conductive polymer, for example, introduces functional groups such as —COOH, —NCO, epoxy group, —OH, and —NH ₂ into the polymer chain of the conductive polymer that is soluble in organic solvents and insoluble in water. The compound can be obtained by reacting this active site with a compound having a polymerizable unsaturated group.

  Specific examples of the curable conductive polymer that is soluble in an organic solvent and insoluble in water include the following general formulas (1a) to (1c), general formulas (2a) to (2c), and general formulas (3a) to (3c). ), And a polymer obtained by blending a polymerization initiator with the monomer represented by polymerization.

In each of the general formulas (1a) to (3c), each R ¹ independently represents a vinyl group or a (meth) acryloyl group. R < ² > shows a hydrogen atom and a C1-C6 alkyl group each independently, and a C1-C3 alkyl group is preferable. R < ³ > shows a C1-C6 alkyl group each independently. Moreover, x is an integer of 1-6, Preferably it is an integer of 2-6. m is an integer of 0-12, preferably an integer of 4-12. n is an integer of 1 to 12, and preferably an integer of 4 to 12. a is an integer of 1-2, b and c are integers of 1-4.
Examples of the alkyl group having 1 to 6 carbon atoms represented by R ² and R ³ include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an s-butyl group, an isobutyl group, a pentyl group, A hexyl group etc. are mentioned.

  The content of the curable conductive polymer is preferably 70 to 100% by mass, more preferably 85 to 100% by mass, still more preferably 95 to 100% by mass, and still more preferably 95 to 99.% in the coating layer forming material. 9% by mass. In addition, the coating layer forming material may contain other additives such as a polymerization initiator as desired as long as the effects of the present invention are not impaired.

  The coating layer is formed by applying a solution obtained by dissolving the above-described coating layer forming material in an organic solvent onto the buffer layer by a known coating method such as a spin coating method, and then heating and drying the coating film. Can be formed.

The thickness of the coating layer 13 is 1 to 50 nm, preferably 3 to 45 nm, more preferably 5 to 40 nm, and still more preferably from the viewpoint of improving smoothness and reducing the surface resistivity of the conductive laminate. 7-30 nm. If it is less than 1 nm, the arithmetic average roughness (Ra) of the coating layer to be formed becomes large and the smoothness is inferior. On the other hand, when it exceeds 50 nm, the surface resistivity of the conductive laminate is increased.
The ratio of the thickness of the coating layer to the buffer layer [coating layer / buffer layer] is preferably 1/99 to 50 from the viewpoint of reducing the surface roughness and reducing the surface resistivity of the conductive laminate. / 50, more preferably 3/97 to 30/70, still more preferably 5/95 to 23/77.

[Characteristics of conductive laminate]
In the present invention, the surface roughness of the conductive laminate is evaluated by the arithmetic average roughness (Ra) of the coating layer 13 of the conductive laminate. The value of arithmetic average roughness (Ra) is a value measured based on JIS B 0601: 2001, and more specifically means a value measured by the method described in the examples.
The calculated average roughness (Ra) of the coating layer is 3.00 nm or less, preferably 2.60 nm or less, more preferably 2.30 nm or less, and still more preferably 2.00 nm or less. When the calculated average roughness (Ra) of the coating layer exceeds 3.00 nm, when applied to an organic photoelectric conversion element, a leak current is generated between the electrodes, and the short-circuit current density cannot be sufficiently improved.

  Further, the surface resistivity of the conductive laminate measured from the exposed coating layer side of the conductive laminate of the present invention is 500Ω / □ or less, preferably 350Ω / □ or less, more preferably 280Ω / □. Hereinafter, it is more preferably 235Ω / □ or less. When the surface resistivity of the conductive laminate exceeds 500 Ω / □, it is not preferable because the short-circuit current density decreases when applied to an organic photoelectric conversion element.

  As described above, the conductive laminate of the present invention has excellent surface smoothness and low surface resistivity. Therefore, for example, in the case of an organic photoelectric conversion element, a photoelectric conversion layer or an organic EL element is used between the electrodes. In the case of, an organic device having an organic light emitting layer can be used for the purpose of reducing the contact resistance between the photoelectric conversion layer or the organic light emitting layer and the electrode. Especially, since a short circuit current density can be improved, it can use suitably for an organic photoelectric conversion element.

[Organic photoelectric conversion element]
Next, the organic photoelectric conversion element which has a photoelectric converting layer further on the coating layer of the electroconductive laminated body of this invention is demonstrated.
An organic photoelectric conversion element is an element that generates an electromotive force when irradiated with light energy. In general, an element that converts light energy into electrical energy is provided with an electrode for extracting charges from the photoelectric conversion layer. It is a thing. Examples of organic photoelectric conversion elements include various organic semiconductor device applications such as organic solar cells and photodiodes. Among these, an organic solar cell is suitable for the use of the organic photoelectric conversion element of the present invention. Moreover, a photoelectric converting layer is a layer which receives the photoelectric effect which makes the center of an organic photoelectric conversion element, may consist of a single layer, and may consist of multiple layers.

2 and 3 are cross-sectional views of the organic photoelectric conversion element showing one embodiment of the organic photoelectric conversion element of the present invention.
The organic photoelectric conversion element 2 a shown in FIG. 2 has a photoelectric conversion layer 14 and an electrode 15 in this order on the coating layer 13 of the conductive laminate 1. The photoelectric conversion layer 14 is a layer that receives the photoelectric effect that forms the center of the organic photoelectric conversion element. The photoelectric conversion layer 14 of the organic photoelectric conversion element 2a in FIG. 2 is a layer formed from a mixed material of a p-type semiconductor material (electron-donating material) and an n-type semiconductor material (electron-accepting material). It is configured.
On the other hand, the photoelectric conversion layer 14 of the organic photoelectric conversion element 2b shown in FIG. 3 includes a plurality of layers of a p-type semiconductor layer 14a made of a p-type semiconductor material and an n-type semiconductor layer 14b made of an n-type semiconductor material. ing.

When the photoelectric conversion layer is a single layer, the photoelectric conversion layer 14 is usually formed from an intrinsic semiconductor layer. The intrinsic semiconductor layer is an organic layer having a pn junction interface made of a p-type semiconductor material (electron-donating material) and an n-type semiconductor material (electron-accepting material).
When there are a plurality of photoelectric conversion layers, the photoelectric conversion layer 14 includes a p-type semiconductor layer 14a made of a p-type semiconductor material (electron-donating material) and an n-type made of an n-type semiconductor material (electron-accepting material). The semiconductor layer 14b is composed of an organic layer having a pn junction interface.

  In the intrinsic semiconductor layer, the mass ratio of the p-type semiconductor material to the n-type semiconductor material (p-type semiconductor material / n-type semiconductor material) is preferably 1/10 to 10/1 from the viewpoint of obtaining high photoelectric conversion efficiency. Preferably it is 1/5 to 5/1, more preferably 1/5 to 1/1.

  The p-type semiconductor material in the photoelectric conversion layer is not particularly limited. For example, a condensed polycyclic aromatic low molecular compound such as copper phthalocyanine, a conjugated polymer of a polythiophene derivative such as poly-3-hexylthiophene (P3HT), or the like An oligomer etc. are mentioned.

On the other hand, the n-type semiconductor material is not particularly limited. For example, fullerene compounds such as [6,6] -phenyl C61 butyric acid methyl ester ([6,6] -PCBM or [60] PCBM), triazole Derivatives, phenanthroline derivatives, phosphine oxide derivatives, carbon nanotubes (CNT), derivatives obtained by introducing a cyano group into a poly-p-phenylene vinylene polymer (CN-PPV), and the like. Among these, a fullerene compound is preferable because it is an n-type semiconductor material that is stable and has high carrier mobility.
These p-type semiconductor material and n-type semiconductor material can be used alone or in combination of two or more.

  In addition, the method for forming a photoelectric conversion layer such as an intrinsic semiconductor layer, a p-type semiconductor layer, and an n-type semiconductor layer is not particularly limited, and examples thereof include a coating method such as spin coating and bar coating, and a vacuum deposition method. It is done. Among these, as a method for forming the intrinsic semiconductor layer, a method in which a solution in which a p-type semiconductor material and an n-type semiconductor material are dissolved in a solvent is applied by the above-described application method is preferable. The solvent contained in this solution is not particularly limited, and for example, chlorobenzene, orthodichlorobenzene, chloroform, dichloromethane, toluene, tetrahydrofuran and the like can be used.

The material of the electrode 15 of the organic photoelectric conversion element of the present invention is not particularly limited, but the cathode electrode material has a small energy barrier and a relatively small work function with respect to the LUMO level of the electron-accepting material. Preferable examples include Ag, Al, Pt, Ir, Cr, ZnO, CNT, and alloys and composites thereof.
On the other hand, the material of the anode electrode is preferably an electron donating material having a small HOMO level and energy barrier, a relatively large work function, and more preferably a transparent material. Examples thereof include materials such as tin-doped indium oxide (ITO), IrO ₂ , In ₂ O ₃ , SnO ₂ , indium oxide-zinc oxide (IZO), ZnO (Ga, Al doped), and MoO ₃ .
The method for forming the electrode is not particularly limited, and examples thereof include vacuum deposition and various sputtering methods.

In addition, you may provide the blocking layer 16 between the photoelectric converting layer 14 and the electrode 15 like the organic photoelectric conversion element 2b of FIG. Examples of the material for forming the blocking layer include 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (Bathocuproine; BCP), bis (2-methyl-8-hydroxyquinolinoate) -aluminum ( III) Phenolate (Alq ₂ OPH) and the like.

[Production Example 1]
(Synthesis of Compound (1A) Represented by Formula (1A) below)

First, a compound represented by the following formula (a) was synthesized by a known method.

1.08 g (2.09 mmol) of the compound represented by the above formula (a) is dispersed in 190 mL of dichloromethane at room temperature, 0.9 g of methacrylic acid (manufactured by Tokyo Chemical Industry), 4-N, N-dimethylaminopyridine 1 .28 g and 2.16 g of dicyclohexylcarboxydiimide (DCC) were added and reacted with stirring for 12 hours.
The resulting reaction mixture was filtered through celite to remove solids, and then concentrated under reduced pressure. The resulting concentrate was purified by column chromatography (developing solvent: dichloromethane / n-hexane = 1/1) using a silica gel column (manufactured by Wako Pure Chemicals, product name “C-200”). 0.9624 g (yield 67%) of the compound (1A) represented by the formula (1A) (a curable conductive polymer having a polythiophene skeleton soluble in an organic solvent and insoluble in water) was obtained.

The analysis results of the obtained compound (1A) are shown below.
¹ H-NMR (500 MHz, TMS internal standard, ppm display, solvent: deuterated chloroform, 25 ° C.); 7.03 (2H, d), 6.99 (4H, br), 6.67 (2H, d) 6.09 (1H, d), 5.55 (1H, d), 4.14 (2H, t), 2.80 (4H, br), 1.95 (3H, t), 1.68 ( 6H, br), 1.42-1.30 (10H, br), 0.90 (3H, t). Mass spectrometry (EI-MS); m / Z = 584 (M +).

[Production Example 2]
(Preparation of compound (1A) -containing coating solution)
The compound (1A) represented by the above formula (1A) synthesized in Production Example 1 was dissolved in chlorobenzene (manufactured by Sigma-Aldrich) to prepare a solution having a concentration of 1% by mass. To the solution, 2,2-dimethoxy-1,2-diphenylethane-1-one (manufactured by Nagase Sangyo Co., Ltd., product name “Irgacure 651”) was added as a photoinitiator to 100 parts by mass of the compound (1A). A part by mass was added to prepare a coating solution containing compound (1A). The obtained coating solution was stored at room temperature in a dark place.

[Example 1]
(1) Production of Conductive Laminate A conductive laminate having the configuration shown in FIG. 1 was produced according to the following procedure.
As a substrate 11 with a transparent electrode, an ITO glass substrate subjected to a cleaning treatment using a UV-ozone cleaner “UV253E” (product name, manufactured by Filgen Co., Ltd.) (a glass substrate formed with a tin-doped indium oxide film as a transparent electrode) It was used. On this ITO glass substrate, an aqueous dispersion (solid content) of PEDOT / PSS (manufactured by Japan Agfa Materials, trade name “HBS5”, water-based conductive polymer, described as “water-based conductive polymer 1” in Tables 1 and 2). (Concentration: 2.0% by mass) is applied to form a coating film having a thickness of 110 nm after drying, and is heated and dried to cure the coating film. Formed on top.
And on this buffer layer 12, a curable conductive polymer (manufactured by Nissan Chemical Industries, a thermosetting conductive polymer having a polyaniline skeleton soluble in an organic solvent and insoluble in water, in Tables 1 and 2, "curable conductive" Coating solution is formed using a solution (solvent: dimethylacetamide, solid content concentration: 1.0% by mass), and a coating film is formed by heating to a thickness of 25 nm. Then, the coating film was cured, and a coating layer 13 having a thickness of 25 nm was formed on the buffer layer 12 to produce the conductive laminate 1.

(2) Production of Organic Photoelectric Conversion Element An organic photoelectric conversion element having the configuration shown in FIG. 2 was produced by the following procedure.
As a p-type semiconductor material, poly-3-hexylthiophene (P3HT) (manufactured by Merck, product name “SP001”) 69 mg, and as an n-type semiconductor material, 51 mg of phenyl C61 butyric acid methyl ester (PCBM) (manufactured by Frontier Carbon Co., Ltd.) Used and dissolved in dehydrated chlorobenzene (3.0 ml) to prepare a coating liquid for forming a photoelectric conversion layer which is an intrinsic semiconductor layer.
Then, in the glove box substituted with dry nitrogen, the coating solution prepared by applying the coating solution prepared on the coating layer of the conductive laminate described above onto the coating layer 13 so that the thickness after drying becomes 150 nm. Then, the coating film was cured by heating and drying at 150 ° C. for 10 minutes using a hot plate to form a photoelectric conversion layer 14 having a thickness of 150 nm.
Next, the laminate was transferred to a vacuum deposition machine (manufactured by ALS Technology) without being exposed to the atmosphere, and an aluminum layer (thickness: 100 nm) was formed as an electrode 15 on the photoelectric conversion layer 14 at a degree of vacuum of 3 × 10 ⁻⁴ Pa or less. , An area of 0.55 cm ² ) was laminated by vacuum vapor deposition to produce an organic photoelectric conversion element.

[Example 2]
A conductive laminate and an organic photoelectric conversion element were produced in the same manner as in Example 1 except that the thickness of the coating layer was 10 nm.

[Example 3]
An aqueous dispersion (solid content concentration: 2.5 mass%) of doped polyaniline (manufactured by Nissan Chemical Industries, trade name “D1033W”, aqueous conductive polymer, described as “aqueous conductive polymer 2” in Tables 1 and 2) ) Was used to produce a conductive laminate and an organic photoelectric conversion element in the same manner as in Example 1 except that a buffer layer having a thickness of 110 nm was formed.

[Example 4]
Using the compound (1A) -containing coating solution prepared in Production Example 2 (solvent: chlorobenzene, solid content concentration: 1.0% by mass), a coating film is formed by coating so that the thickness after drying is 25 nm. After heating and drying at 120 ° C. in the atmosphere, xenon lamp light is irradiated in the atmosphere for 5 minutes, photopolymerized to cure the coating film, and has a polythiophene skeleton that is soluble in organic solvents and insoluble in water A conductive laminate in the same manner as in Example 1 except that a coating layer having a thickness of 25 nm made of a conductive polymer (referred to as “curable conductive polymer 2” in Tables 1 and 2) is formed on the buffer layer. And the organic photoelectric conversion element was produced.

[Comparative Example 1]
An aqueous dispersion of PEDOT / PSS (trade name “Clevios P AI4083”, water-based conductive polymer, referred to as “water-based conductive polymer 3” in Tables 1 and 2) without forming a coating layer (Solid content concentration: 1.0% by mass), except that a 40 nm thick buffer layer was formed on the substrate, a conductive laminate in which a coating layer was not formed in the same manner as in Example 1 and An organic photoelectric conversion element was produced.

[Comparative Example 2]
Without forming a coating layer, PEDOT / PSS (Nippon Agfa Materials, trade name “HBS5”, aqueous conductive polymer (aqueous conductive polymer 1)) aqueous dispersion (solid content concentration: 2.0 mass%) A conductive laminate and an organic photoelectric conversion element in which a coating layer was not formed were produced in the same manner as in Example 1 except that a buffer layer having a thickness of 110 nm was formed on the substrate.

[Comparative Example 3]
A solution of a curable conductive polymer (manufactured by Nissan Chemical Industries, Ltd., a thermosetting conductive polymer having a polyaniline skeleton soluble in an organic solvent and insoluble in water (curable conductive polymer 1)) without forming a coating layer ( The conductive layer with no coating layer formed in the same manner as in Example 1 except that a 25 nm thick buffer layer was formed on the substrate using a solvent: dimethylacetamide (solid content concentration: 1.0 mass%). Conductive laminate and organic photoelectric conversion element were prepared.

[Comparative Example 4]
An aqueous dispersion (solid content concentration: 2.5% by mass) of doped polyaniline (manufactured by Nissan Chemical Industries, product name “D1033W”, aqueous conductive polymer (aqueous conductive polymer 2)) without forming a coating layer A conductive laminate and an organic photoelectric conversion element in which a coating layer was not formed were produced in the same manner as in Example 1 except that a buffer layer having a thickness of 110 nm was formed on the substrate.

[Comparative Example 5]
Using the compound (1A) -containing coating solution (solvent: chlorobenzene, solid content concentration: 1.0% by mass) prepared in Production Example 2 without forming a coating layer, the thickness after drying is 25 nm. After coating with heat and drying at 120 ° C. in the air, it is irradiated with xenon lamp light in the air for 5 minutes, photopolymerized to cure the coating, soluble in organic solvents and dissolved in water. The coating layer was formed in the same manner as in Example 1 except that a 25 nm thick buffer layer made of a curable conductive polymer (curable conductive polymer 2) having an insoluble polythiophene skeleton was formed on the substrate. A conductive laminate and an organic photoelectric conversion element were prepared.

[Comparative Example 6]
Using an aqueous dispersion (solid content concentration: 1.0% by mass) of PEDOT / PSS (manufactured by HC Starck, trade name “Clevios P AI4083”, aqueous conductive polymer (aqueous conductive polymer 3)), A conductive laminate and an organic photoelectric conversion element were produced in the same manner as in Example 1 except that a coating layer having a thickness of 70 nm was formed on the buffer layer.

[Comparative Example 7]
Using an aqueous dispersion (solid content concentration: 1.0% by mass) of PEDOT / PSS (manufactured by HC Starck, trade name “Clevios P AI4083”, aqueous conductive polymer (aqueous conductive polymer 3)), A conductive laminate and an organic photoelectric conversion element were produced in the same manner as in Example 1 except that a coating layer having a thickness of 40 nm was formed on the buffer layer.

[Comparative Example 8]
A solution (solvent: dimethylacetamide, solid content) of a curable conductive polymer (manufactured by Nissan Chemical Industries, a thermosetting conductive polymer having a polyaniline skeleton soluble in an organic solvent and insoluble in water (curable conductive polymer 1)) A buffer layer having a thickness of 25 nm was formed on the substrate using a concentration of 1.0% by mass), and PEDOT / PSS (trade name “HBS5” manufactured by Japan Agfa Materials Co., Ltd.), water-based conductive polymer (water-based conductive polymer 1). )) In the same manner as in Example 1 except that a coating layer having a thickness of 110 nm was formed on the buffer layer using an aqueous dispersion (solid content concentration: 2.0% by mass). A photoelectric conversion element was produced.

[Comparative Example 9]
Using an aqueous dispersion (solid content concentration: 1.0% by mass) of PEDOT / PSS (manufactured by HC Starck, trade name “Clevios P AI4083”, aqueous conductive polymer (aqueous conductive polymer 3)), A buffer layer having a thickness of 40 nm is formed on the substrate, and an aqueous dispersion (solid content concentration: 2) of PEDOT / PSS (product name “HBS5”, water-based conductive polymer (water-based conductive polymer 1) manufactured by Japan Agfa Materials). 0.0 mass%), a conductive laminate and an organic photoelectric conversion element were produced in the same manner as in Example 1 except that a coating layer having a thickness of 110 nm was formed on the buffer layer.

[Example 5]
The organic photoelectric conversion device having the configuration shown in FIG. 3 was produced by the following procedure.
Copper phthalocyanine (trade name “P1005”, manufactured by Tokyo Chemical Industry Co., Ltd.) 60 nm, n-type semiconductor as a p-type semiconductor material on the coating layer of the conductive laminate produced in Example 1 by a vapor deposition machine (manufactured by ALS Technology). As a material, C60 fullerene (manufactured by Frontier Carbon, trade name “Nanom Purple SU”) of 60 nm was used, and vapor deposition was performed in this order to form a photoelectric conversion layer 14 including a p-type semiconductor layer 14a and an n-type semiconductor layer 14b. Furthermore, 100 nm of silver was laminated | stacked as 10 nm and the electrode 15 with the blocking layer 16 (Basocproine (product made from Lumitec)), and the organic photoelectric conversion element was produced.

[Example 6]
On the coating layer of the conductive laminate produced in Example 3, a photoelectric conversion layer, a blocking layer, and an electrode were sequentially formed in the same manner as in Example 5 to produce an organic photoelectric conversion element.

[Example 7]
On the coating layer of the conductive laminate produced in Example 4, a photoelectric conversion layer, a blocking layer, and an electrode were sequentially formed in the same manner as in Example 5 to produce an organic photoelectric conversion element.

[Comparative Example 10]
On the buffer layer of the conductive laminate produced in Comparative Example 1, a photoelectric conversion layer, a blocking layer, and an electrode were sequentially formed in the same manner as in Example 5 to produce an organic photoelectric conversion element.

[Comparative Example 11]
On the buffer layer of the conductive laminate produced in Comparative Example 2, a photoelectric conversion layer, a blocking layer, and an electrode were formed in this order by the same method as in Example 5 to produce an organic photoelectric conversion element.

[Comparative Example 12]
On the buffer layer of the conductive laminate produced in Comparative Example 3, a photoelectric conversion layer, a blocking layer, and an electrode were sequentially formed in the same manner as in Example 5 to produce an organic photoelectric conversion element.

[Comparative Example 13]
On the buffer layer of the conductive laminate produced in Comparative Example 4, a photoelectric conversion layer, a blocking layer, and an electrode were sequentially formed in the same manner as in Example 5 to produce an organic photoelectric conversion element.

[Comparative Example 14]
On the buffer layer of the conductive laminate produced in Comparative Example 5, a photoelectric conversion layer, a blocking layer, and an electrode were formed in this order by the same method as in Example 5 to produce an organic photoelectric conversion element.

[Comparative Example 15]
As a substrate with a transparent electrode, the ITO glass substrate used in Example 1 was used, and a photoelectric conversion layer, a blocking layer, and an electrode were formed on the ITO glass substrate in the same manner as in Example 5, An organic photoelectric conversion element in which a buffer layer and a coating layer were not formed was produced.

  Tables 1 and 2 show various physical property values of the conductive laminate and the organic photoelectric conversion element produced as described above. In Tables 1 and 2, the thickness of each layer, the surface resistivity of the buffer layer, the coating layer, and the conductive laminate, the arithmetic average roughness (Ra), and the short-circuit current density (Jsc) of the organic photoelectric conversion element are as follows: It is a value measured based on the method.

(1) Thickness of each layer of the conductive laminate The thickness was measured using a step meter “Dektak 150” (product name, manufactured by Nippon Bico Co., Ltd.).

(2) Surface resistivity of buffer layer, coating layer, and conductive laminate The values of the surface resistivity of the buffer layer, coating layer, and conductive laminate are defined in JIS K7194 by preparing the following test samples. Based on the four-terminal method, the resistivity was measured using a “Loresta GP MCP-T600” (product name, manufactured by Mitsubishi Chemical Corporation).
In addition, since the comparative example 15 is only a board | substrate, this surface resistivity is not measured. Moreover, since the conductive laminates of Comparative Examples 1 to 5 and 10 to 15 do not have a coating layer, the surface resistivity of the coating layer is not measured, and the buffer layer test sample and the conductive laminate are not measured. Since the body test samples are the same, the surface resistivity values of the buffer layer and the conductive laminate are the same.
(Buffer layer test sample)
On the PET film (product name “PET-A4300”, manufactured by Toyobo Co., Ltd.) having a thickness of 50 μm, according to the forming method described in each of the following Examples and Comparative Examples, using the same material, the same film thickness is obtained. A single layer consisting only of the buffer layer was formed to prepare a test sample.
(Coating layer test sample)
On the PET film (product name “PET-A4300” manufactured by Toyobo Co., Ltd.) having a thickness of 50 μm, according to the method for forming a coating layer described in each of the following examples and comparative examples, the same film thickness is used. Thus, a single layer consisting only of the coating layer was formed to prepare a test sample.
(Test sample of conductive laminate)
On the PET film (product name “PET-A4300”, manufactured by Toyobo Co., Ltd.) having a thickness of 50 μm, according to the forming method described in each of the following Examples and Comparative Examples, using the same material, the same film thickness is obtained. A buffer layer and a coating layer were formed on the buffer layer to prepare a test sample.

(3) Arithmetic mean roughness (Ra)
The arithmetic average roughness (Ra) of the covering layer (the buffer layer in the case of the conductive laminate in which the covering layer is not formed) exposed from the produced conductive laminate is determined based on the provisions of JIS B 0601: 2001. , Using a scanning probe microscope “SPI3800N” (product name, manufactured by Seiko Instruments Inc.).

(4) Short-circuit current density (Jsc) of organic photoelectric conversion element
About the produced organic photoelectric conversion element, using a solar simulator (manufactured by Wacom Denso, product name “WXS-50S-1.5”) and a voltage-current generator (manufactured by ADC, product name “R6243”). It was measured. The effective area of the produced organic photoelectric conversion elements was 0.055 cm ² in all cases.

From Tables 1 and 2, the conductive laminate of the present invention has a small surface roughness and a low surface resistivity. Therefore, the organic photoelectric conversion element using the conductive laminate has an improved short-circuit current density regardless of whether the photoelectric conversion layer is formed by a coating method or a low molecular vapor deposition method.
On the other hand, compared with the Example of this invention, the organic photoelectric conversion element using the electroconductive laminated body of a comparative example shows that the short circuit current density has not fully improved. In addition, since the conductive laminates of Comparative Examples 6, 7, and 9 were formed using a water-based conductive polymer as a coating layer-forming material, they were similarly formed from the water-based conductive polymer when the coating layer was formed. Since the buffer layer was dissolved, the arithmetic average roughness (Ra) of the surface layer was increased, and as a result, the short-circuit current density was not sufficiently improved.

  The conductive laminate of the present invention can be applied as a member of an organic photoelectric conversion element typified by an organic solar battery.

DESCRIPTION OF SYMBOLS 1 Conductive laminated body 2a, 2b Organic photoelectric conversion element 11 Substrate (substrate with transparent electrode)
DESCRIPTION OF SYMBOLS 12 Buffer layer 13 Covering layer 14 Photoelectric conversion layer 14a p-type semiconductor layer 14b n-type semiconductor layer 15 Electrode 16 Blocking layer

Claims (7)

On the substrate, a conductive laminate having a buffer layer having a thickness of 10 to 1000 nm and a coating layer having a thickness of 1 to 50 nm in order,
The surface resistivity of the single layer consisting only of the buffer layer is 1000 Ω / □ or less, and the surface resistivity of the single layer consisting only of the coating layer is 10 ⁵ to 10 ¹⁰ Ω / □,
The arithmetic average roughness (Ra) of the coating layer is 3.00 nm or less, and the surface resistivity of the conductive laminate measured from the exposed coating layer side of the conductive laminate is 500 Ω / □ or less. Because
The material for forming the coating layer, soluble in organic solvents viewed contains insoluble curing conductive polymer in water, the curable conductive polymer, polythiophene, polypyrrole, and is selected from polyaniline, soluble in an organic solvent A side chain of a conductive polymer that is soluble in an organic solvent and insoluble in water, selected from a thermosetting conductive polymer obtained by modifying a soluble and insoluble conductive polymer, or polythiophene, polypyrrole, and polyaniline And a conductive laminate, which is an ultraviolet curable conductive polymer having a polymerizable unsaturated group selected from a vinyl group and a (meth) acryloyl group .   The conductive laminate according to claim 1, wherein the material forming the buffer layer includes a water-based conductive polymer. The conductive laminate according to claim 1 or 2 , wherein a ratio of the thickness of the coating layer to the buffer layer (coating layer / buffer layer) is from 1/99 to 50/50. Wherein the substrate is an electrode-attached substrate, electroconductive laminate according to any one of claims 1-3. The organic photoelectric conversion element which has the electroconductive laminated body in any one of Claims 1-4 . The organic photoelectric conversion element according to claim 5 , further comprising a photoelectric conversion layer on the coating layer of the conductive laminate, and an electrode on the photoelectric conversion layer. The photoelectric conversion layer includes a single layer formed of a mixed material of a p-type semiconductor material and an n-type semiconductor material, or a p-type semiconductor layer formed of a p-type semiconductor material and an n-type semiconductor layer formed of an n-type semiconductor material. The organic photoelectric conversion element according to claim 6 which is a multi-layer.