JP5413055B2 - Organic photoelectric conversion element, solar cell using the same, and optical sensor array - Google Patents

Description

  The present invention relates to an organic photoelectric conversion element, a solar cell, and an optical sensor array. More specifically, the present invention relates to a bulk heterojunction type organic photoelectric conversion element, a solar cell using the organic photoelectric conversion element, and an optical array sensor.

  Due to the recent rise in fossil energy, there is a demand for a system that can generate power directly from natural energy. Solar cells using single-crystal / polycrystalline / amorphous Si, compound-based solar cells such as GaAs and CIGS, or Dye-sensitized photoelectric conversion elements (Gretzel cells) have been proposed and put into practical use.

  However, the cost of generating electricity with these solar cells is still higher than the price of electricity generated and transmitted using fossil fuels, which has hindered widespread use. In addition, since heavy glass must be used for the substrate, reinforcement work is required at the time of installation, which is one of the causes that increase the power generation cost.

  In this situation, as a solar cell that can achieve a power generation cost lower than that of fossil fuel, an electron donor layer (p-type semiconductor layer) and an electron acceptor layer ( There has been proposed a bulk heterojunction photoelectric conversion element sandwiching a bulk heterojunction layer mixed with an n-type semiconductor layer.

  These bulk heterojunction solar cells are formed by a coating process except for the anode and cathode, and are expected to be able to be manufactured at high speed and at low cost. There is. Furthermore, unlike the above Si-based solar cells, compound semiconductor-based solar cells, dye-sensitized solar cells, etc., there is no process at a temperature higher than 160 ° C., so it is expected that it can be formed on a cheap and lightweight plastic substrate. Is done.

  The photoelectric conversion efficiency representing the performance of the solar cell is calculated by the product of short circuit current (Jsc) × open circuit voltage (Voc) × fill factor (FF). In order to obtain a higher short circuit current (Jsc), for example, organic It has been reported that high photoelectric conversion efficiency can be obtained by using a material having high solubility and carrier mobility in an electroluminescence element (organic EL element) as a photoelectric conversion material of an organic photoelectric conversion element (non-patent) References 1-3 and Patent References 1, 2).

  The photoelectric conversion process can be broadly divided into (1) absorption of incident light, (2) generation of charge, (3) transport of charge in a thin film, and (4) charge collection at an electrode. If a low bandgap material is used as the p-type material to satisfy (), the energy level does not match that of the n-type molecule, so that the efficiency of (2) is reduced or the charge mobility is low (3 ) Does not occur smoothly, and does not lead to improvement in conversion efficiency, and in order to obtain a device with high photoelectric conversion efficiency, a material that simultaneously improves the processes of (1) to (4) is required. . In addition, even if the charge mobility as a single material is high, the performance of the device is determined by the property of the material in the bulk heterojunction layer as a nano-level structure. Therefore, in order to obtain a device having high photoelectric conversion efficiency, A material that satisfies the performance has been awaited.

  The curve factor is closely related to the internal resistance of the photoelectric conversion element, and it is known that lowering the resistance of the organic thin film and improving the charge separation efficiency (improving rectification) are effective for improving the curve factor. Yes.

  There is a disclosure that the charge separation efficiency can be improved by inserting a hole blocking layer made of bathocuproine (BCP) as in the organic EL element, and the photoelectric conversion efficiency can be improved (for example, see Patent Document 3). Since these materials have high crystallinity and low solubility, it is difficult to apply them to a highly productive coating method, and the durability is not sufficient.

  A compound having a structure similar to the compound used in the present invention has already been disclosed (see, for example, Patent Document 4 and Non-Patent Document 4), but there is no description used as a material for an organic photoelectric conversion element. The characteristics as a conversion element material are hardly known, and it was impossible to suggest that the compound according to the present invention is very excellent as an organic photoelectric conversion element material.

JP 2008-106239 A JP 2008-106240 A US Pat. No. 6,580,0027 B2 JP 2008-056630 A

Adv. Mater. Vol. 15, p988 (2003) J. et al. Am. Chem. Soc. Vol. 128, p8980 (2006) App. Phy. Let. Vol. 92,033307, (2008) Aiko Fukazawa, et al. Org. Lett. , Vol. 10, no. 5,913-916,2008

  The objective of this invention is providing the organic photoelectric conversion element which has a high fill factor, an open circuit voltage, and photoelectric conversion efficiency, and has durability, a solar cell using the same, and an optical sensor array.

  The said subject of this invention can be achieved by the following structures.

1. An organic photoelectric conversion element having a cathode, an anode, and a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are mixed, and is represented by at least the following general formula (1) between the cathode and the anode. An organic photoelectric conversion device comprising a layer containing a compound having a partial structure. However, the case where the compound having the partial structure represented by the following general formula (1) is the following compound (3) is excluded.

２．前記一般式（１）で表される部分構造を有する化合物が、下記一般式（２）で表される部分構造を有する化合物であることを特徴とする前記１に記載の有機光電変換素子。 (In the formula, n01 represents 1 and R ¹ represents a substituent.)

2. 2. The organic photoelectric conversion device according to 1 above, wherein the compound having a partial structure represented by the general formula (1) is a compound having a partial structure represented by the following general formula (2).

（式中、ｎ０１は０または１を表し、Ｒ ^１ は置換基を表す。）
４．前記一般式（１）で表される部分構造を有する化合物が、下記一般式（２）で表される部分構造を有する化合物であることを特徴とする前記３に記載の有機光電変換素子。

（式中、ｎ０１は０または１を表し、Ｒ ^１ は置換基を表す。）
５．陰極、陽極、及びｐ型半導体材料とｎ型半導体材料が混合されたバルクへテロジャンクション層を有する有機光電変換素子であって、前記陰極と陽極の間に、少なくとも下記一般式（３）で表される部分構造を有する化合物を含有する層を有することを特徴とする有機光電変換素子。 (In the formula, n01 represents 1 and R ¹ represents a substituent.)
3. An organic photoelectric conversion element having a cathode, an anode, and a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are mixed, and is represented by at least the following general formula (1) between the cathode and the anode. An organic photoelectric conversion device comprising a layer containing a compound having a partial structure, wherein the layer is the bulk heterojunction layer.

(In the formula, n01 represents 0 or 1, and R ¹ represents a substituent.)
4). 4. The organic photoelectric conversion device as described in 3 above, wherein the compound having a partial structure represented by the general formula (1) is a compound having a partial structure represented by the following general formula (2).

(In the formula, n01 represents 0 or 1, and R ¹ represents a substituent.)
5 . An organic photoelectric conversion element having a cathode, an anode, and a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are mixed, and is represented by at least the following general formula (3) between the cathode and the anode. organic photoelectric conversion element characterized by having a layer containing a compound having a partial structure.

(In the formula, n01 and n02 each represent 0 or 1, and R ¹ and R ² each represent a substituent.)
6 . 6. The organic photoelectric conversion device as described in 5 above, wherein the compound having a partial structure represented by the general formula (3) is a compound having a partial structure represented by the following general formula (4).

(In the formula, n01 and n02 each represent 0 or 1, and R ¹ and R ² each represent a substituent.)
7 . 7. The organic photoelectric conversion device as described in 6 above, wherein the compound having a partial structure represented by the general formula (4) is a compound having a partial structure represented by the following general formula (5).

(In the formula, n01 and n02 each represent 0 or 1, and R ¹ and R ² each represent a substituent.)
8 . In the above formulas (1) to (5), n01 and n02 is an organic photoelectric conversion element of any one of the 3-7, which is a 1.

9 . 9. The organic photoelectric conversion device according to any one of 1 to 8 , wherein the compound having a partial structure represented by the general formula (1) to the general formula (5) is a low molecular compound.

10 . Wherein 1, 2, wherein the general formula (1) a layer containing a compound having a partial structure represented by - formula (5), characterized in that present between the bulk and the heterojunction layer and the cathode the organic photoelectric conversion element according to any one of 5-9.

11 . Any of the above-mentioned 1 , 2, 5 to 9 , wherein the layer containing the compound having the partial structure represented by the general formula (1) to the general formula (5) is the bulk heterojunction layer The organic photoelectric conversion element of Claim 1.

12 . 12. The layer according to any one of 1 to 11 above, wherein the layer containing a compound having a partial structure represented by the general formula (1) to the general formula (5) is produced by a solution coating method. Organic photoelectric conversion element.

13 . Solar cell characterized by comprising the organic photoelectric conversion element of any one of the 1 to 12.

14 . Photosensor array organic photoelectric conversion element of any one of the 1 to 12, characterized in that are arranged in a array.

  According to the present invention, an organic photoelectric conversion element having high fill factor, open-circuit voltage, photoelectric conversion efficiency, and durability, a solar cell using the same, and an optical sensor array can be provided.

It is sectional drawing which shows the solar cell which consists of a bulk hetero junction type organic photoelectric conversion element. It is sectional drawing which shows the solar cell which consists of an organic photoelectric conversion element provided with the photoelectric converting layer of the three-layer structure of p-i-n. It is sectional drawing which shows the solar cell which consists of an organic photoelectric conversion element provided with a tandem-type bulk heterojunction layer. It is a figure which shows the structure of an optical sensor array.

  When the present inventors diligently examined the above problem, they contain a compound having a partial structure represented by the general formula (1) to the general formula (5) between the bulk heterojunction layer and the cathode. It has been found that the above problem can be achieved by the presence of a layer. Furthermore, a layer containing a compound having a partial structure represented by the general formulas (1) to (5) exists between the bulk heterojunction layer and the cathode, or the bulk heterojunction layer It was found that it is preferable.

  Hereinafter, details of each component according to the present invention will be sequentially described.

[Compound having a partial structure represented by general formula (1) to general formula (5)]
First, the compound which has the partial structure represented by General formula (1)-General formula (5) in this invention is demonstrated.

In General Formula (1) to General Formula (5), n01 and n02 each represent 0 or 1, and R ¹ and R ² each represent a substituent. Substituents that can be substituted with compounds having a partial structure of general formula (1) to general formula (5), and substitution represented by R ¹ and R ² in general formula (1) to general formula (5) The group is not limited, but preferred examples thereof include an alkyl group, a cycloalkyl group, an alkynyl group, an aromatic hydrocarbon ring group (also referred to as an aromatic carbocyclic group, an aryl group, etc., for example, a phenyl group, p-chlorophenyl Group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, pyridyl group) , Pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1, , 4-triazol-1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl Group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (one of the carbon atoms constituting the carboline ring of the carbolinyl group is a nitrogen atom) Quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, etc.), heterocyclic group (for example, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group, cycloalkoxy group , Aryloxy group, alkyl Ruthio, cycloalkylthio, arylthio, alkoxycarbonyl, aryloxycarbonyl, sulfamoyl, acyl, acyloxy, amide, carbamoyl, ureido, sulfinyl, alkylsulfonyl, arylsulfonyl or heteroaryl Examples include a sulfonyl group, an amino group, a halogen atom, a fluorinated hydrocarbon group, a cyano group, a nitro group, a hydroxy group, a mercapto group, and a silyl group. Particularly preferred examples include an alkyl group, an aromatic hydrocarbon ring group, and an aromatic heterocyclic group.

  In the present invention, from the viewpoint that high-purity purification is possible and a thin film having high mobility can be obtained, the compounds having the partial structures represented by the general formulas (1) to (5) are low. It is preferably a molecular compound. In the present invention, the low molecular weight compound means a single molecule having no distribution in the molecular weight of the compound. On the other hand, the polymer compound means an aggregate of compounds having a certain molecular weight distribution by reacting a predetermined monomer. However, in practical terms, when defining by molecular weight, a compound having a molecular weight of 3000 or less is preferably classified as a low molecular compound. More preferably, it is 2500 or less, More preferably, it is 2000 or less. On the other hand, a compound having a molecular weight of 3000 or more, more preferably 5000 or more, and further preferably 10,000 or more is classified as a polymer compound. The molecular weight can be measured by gel permeation chromatography (GPC).

  In the present invention, the effect can be exhibited by containing the compound having the partial structure represented by the general formula (1) to the general formula (5) between the cathode and the anode of the organic photoelectric conversion element. Of the compounds having the partial structure represented by the general formulas (1) to (5), a compound in which n01 and n02 are 1 is a material for an electron transport layer (also serves as a hole blocking layer) or a p-type semiconductor material for a bulk heterojunction layer It can be used more suitably, and effects such as improvement of the fill factor, photoelectric conversion efficiency, and device durability can be obtained.

  Hereinafter, although the example of the compound which has the partial structure represented by General formula (1)-General formula (5) based on this invention is given, this invention is not limited to these. In addition, the compound which concerns on this invention can be easily obtained with reference to the synthesis method of Unexamined-Japanese-Patent No. 2008-056630 and patent 4211920.

  In the said compound, n represents 2-100.

Synthesis Example (Synthesis of Compound Example 101)
Compound Example 101 was synthesized according to the following scheme.

  Compound A was synthesized according to Japanese Patent Application Laid-Open No. 2008-056630. 4.3 g of the compound A obtained, 1.7 g of 2-thiopheneboronic acid, 500 mg of palladium (0) tetrakis (triphenylphosphine) were dissolved in tetrahydrofuran, and several drops of a 20% by mass sodium carbonate solution were added thereto. Reacted for hours. After completion of the reaction, ethyl acetate and water were added for liquid separation, and the organic layer was extracted. After evaporating the solvent under reduced pressure, the residue was purified by silica gel column chromatography to obtain 3.2 g of Compound B.

  Next, after 3.2 g of compound B was dissolved in carbon tetrachloride to which 1.7 g of N-bromosuccinimide and a catalyst amount of azoisobutyronitrile (AIBN) were added, the reaction was carried out at 50 ° C. for 5 hours, followed by bromination. Then, ethyl acetate and water were added to carry out a liquid separation operation, and the organic layer was extracted. After evaporating the solvent under reduced pressure, the residue was purified by silica gel column chromatography to obtain 3.8 g of Compound C.

  Thereafter, Adv. Mater. With reference to 2007, 19, p2295, 3.5 g of Compound Example 101 was synthesized from Compound C via Compound D.

[Organic photoelectric conversion element and solar cell]
FIG. 1 is a cross-sectional view showing an example of a solar cell composed of a bulk heterojunction organic photoelectric conversion element. In FIG. 1, a bulk heterojunction organic photoelectric conversion element 10 has an anode 12, a hole transport layer 17, a bulk heterojunction layer photoelectric conversion section 14, an electron transport layer 18, and a cathode 13 in this order on one surface of a substrate 11. Are stacked.

  The substrate 11 is a member that holds the anode 12, the photoelectric conversion unit 14, and the cathode 13 that are sequentially stacked. In the present embodiment, since light that is photoelectrically converted enters from the substrate 11 side, the substrate 11 can transmit the light that is photoelectrically converted, that is, with respect to the wavelength of the light to be photoelectrically converted. It is a transparent member. As the substrate 11, for example, a glass substrate or a resin substrate is used. The substrate 11 is not essential. For example, the bulk heterojunction type organic photoelectric conversion element 10 may be configured by forming the anode 12 and the cathode 13 on both surfaces of the photoelectric conversion unit 14.

  The photoelectric conversion unit 14 is a layer that converts light energy into electric energy, and includes a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are uniformly mixed. The p-type semiconductor material functions relatively as an electron donor (donor), and the n-type semiconductor material functions relatively as an electron acceptor (acceptor). Here, the electron donor and the electron acceptor are “an electron donor in which, when light is absorbed, electrons move from the electron donor to the electron acceptor to form a hole-electron pair (charge separation state)”. And an electron acceptor ”, which does not simply donate or accept electrons like an electrode, but donates or accepts electrons by a photoreaction.

  In FIG. 1, light incident from the anode 12 through the substrate 11 is absorbed by the electron acceptor or electron donor in the bulk heterojunction layer of the photoelectric conversion unit 14, and electrons move from the electron donor to the electron acceptor. A hole-electron pair (charge separation state) is formed. The generated electric charge is caused by an internal electric field, for example, when the work function of the anode 12 and the cathode 13 is different, the electrons pass between the electron acceptors and the holes are electron donors due to the potential difference between the anode 12 and the cathode 13. The photocurrent is detected by passing through different electrodes to different electrodes. For example, when the work function of the anode 12 is larger than that of the cathode 13, electrons are transported to the anode 12 and holes are transported to the cathode 13. If the magnitude of the work function is reversed, electrons and holes are transported in the opposite direction. In addition, the transport direction of electrons and holes can be controlled by applying a potential between the anode 12 and the cathode 13.

  Although not shown in FIG. 1, other layers such as a hole blocking layer, an electron blocking layer, an electron injection layer, a hole injection layer, or a smoothing layer may be included.

  As a more preferable configuration, the photoelectric conversion unit 14 has a so-called p-i-n three-layer configuration (FIG. 2). A normal bulk heterojunction layer is a 14i layer composed of a mixture of a p-type semiconductor material and an n-type semiconductor layer, but is sandwiched between a 14p layer composed of a single p-type semiconductor material and a 14n layer composed of a single n-type semiconductor material. As a result, the rectification of holes and electrons becomes higher, loss due to recombination of charge-separated holes and electrons is reduced, and higher photoelectric conversion efficiency can be obtained.

  Furthermore, it is good also as a tandem-type structure which laminated | stacked such a photoelectric conversion element for the purpose of the improvement of sunlight utilization factor (photoelectric conversion efficiency). FIG. 3 is a cross-sectional view showing a solar cell composed of an organic photoelectric conversion element including a tandem bulk heterojunction layer. In the case of the tandem configuration, the anode 12 and the first photoelectric conversion unit 14 ′ are sequentially stacked on the substrate 11, the charge recombination layer 15 is stacked, the second photoelectric conversion unit 16, and then the cathode 13 are stacked. By stacking, a tandem structure can be obtained. The second photoelectric conversion unit 16 may be a layer that absorbs the same spectrum as the absorption spectrum of the first photoelectric conversion unit 14 'or may be a layer that absorbs a different spectrum, but is preferably a layer that absorbs a different spectrum. is there. Further, the first photoelectric conversion unit 14 ′ and the second photoelectric conversion unit 16 may both have the above-described three-layer configuration of pin.

  Below, the material which comprises these layers is described.

(P-type semiconductor material)
In the present invention, as the p-type semiconductor material, a compound having a partial structure represented by the general formula (1) to the general formula (5) is preferably used. Among them, a compound in which n01 and n02 are 1 is used. More preferably used. In addition to the above compounds, other known p-type semiconductor materials (such as condensed polycyclic aromatic low molecular weight compounds and conjugated polymers) may be used in combination.

  Examples of the condensed polycyclic aromatic low-molecular compound include anthracene, tetracene, pentacene, hexacene, heptacene, chrysene, picene, fluorene, pyrene, peropyrene, perylene, terylene, quaterylene, coronene, ovalene, circumanthracene, bisanthene, zesulene, Compounds such as heptazeslen, pyranthrene, violanthene, isoviolanthene, cacobiphenyl, anthradithiophene, porphyrin, copper phthalocyanine, tetrathiafulvalene (TTF) -tetracyanoquinodimethane (TCNQ) complex, bisethylenetetrathiafulvalene (BEDTTTTF ) -Perchloric acid complexes, and derivatives and precursors thereof.

  Examples of the derivative having the above-mentioned condensed polycycle include WO 03/16599 pamphlet, WO 03/28125 pamphlet, US Pat. No. 6,690,029, JP 2004-107216 A. A pentacene derivative having a substituent described in JP-A-2003-136964, a pentacene precursor described in US Patent Application Publication No. 2003/136964, and the like; Amer. Chem. Soc. , Vol. 127, no. 14, 4986, J.A. Amer. Chem. Soc. , Vol. 123, p9482; Amer. Chem. Soc. , Vol. 130 (2008), no. Examples include acene compounds substituted with a trialkylsilylethynyl group described in 9,2706, and porphyrin compounds described in JP-A-2008-16834.

  As the conjugated polymer, for example, a polythiophene such as poly-3-hexylthiophene (P3HT) and an oligomer thereof, or a technical group described in Technical Digest of the International PVSEC-17, Fukuoka, Japan, 2007, P1225. Polythiophene, Nature Material, (2006) vol. 5, p328, polythiophene-thienothiophene copolymer, polythiophene-diketopyrrolopyrrole copolymer described in WO08 / 000664, Adv. Mater. , 2007, p4160, a polythiophene-thiazolothiazole copolymer, Nature Mat. vol. 6 (2007), p497 described in PCPDTBT, etc., polypyrrole and its oligomer, polyaniline, polyphenylene and its oligomer, polyphenylene vinylene and its oligomer, polythienylene vinylene and its oligomer, polyacetylene, polydiacetylene, Examples thereof include polymer materials such as σ-conjugated polymers such as polysilane and polygermane.

  In addition, oligomeric materials instead of polymer materials include thiophene hexamer α-sexual thiophene α, ω-dihexyl-α-sexual thiophene, α, ω-dihexyl-α-kinkethiophene, α, ω-bis (3 Oligomers such as -butoxypropyl) -α-sexithiophene can be preferably used.

(N-type semiconductor material)
The n-type semiconductor material used for the bulk heterojunction layer of the present invention is not particularly limited. Perfluorophthalocyanine), naphthalenetetracarboxylic anhydride, naphthalenetetracarboxylic acid diimide, perylenetetracarboxylic acid anhydride, perylenetetracarboxylic acid diimide and other aromatic carboxylic acid anhydrides and imidized compounds thereof as a skeleton Etc.

  However, fullerene derivatives that can perform charge separation with various p-type semiconductor materials at high speed (˜50 fs) and efficiently are preferable. Fullerene derivatives include fullerene C60, fullerene C70, fullerene C76, fullerene C78, fullerene C84, fullerene C240, fullerene C540, mixed fullerene, fullerene nanotubes, multi-walled nanotubes, single-walled nanotubes, nanohorns (conical), and the like. Partially by hydrogen atom, halogen atom, substituted or unsubstituted alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, cycloalkyl group, silyl group, ether group, thioether group, amino group, silyl group, etc. Examples thereof include substituted fullerene derivatives.

  Among them, [6,6] -phenyl C61-butyric acid methyl ester (abbreviation PCBM), [6,6] -phenyl C61-butyric acid-nbutyl ester (PCBnB), [6,6] -phenyl C61-buty Rick acid-isobutyl ester (PCBiB), [6,6] -phenyl C61-butyric acid-n hexyl ester (PCBH), Adv. Mater. , Vol. 20 (2008), p2116, etc., aminated fullerenes such as JP-A 2006-199674, metallocene fullerenes such as JP-A 2008-130889, and cyclics such as US Pat. No. 7,329,709. It is preferable to use a fullerene derivative having a substituent and having improved solubility, such as fullerene having an ether group.

(Bulk heterojunction layer formation method)
Examples of a method for forming a bulk heterojunction layer in which an electron acceptor and an electron donor are mixed include a vapor deposition method and a coating method (including a casting method and a spin coating method). Among these, the coating method is preferable in order to increase the area of the interface where charges and electrons are separated from each other as described above and to produce a device having high photoelectric conversion efficiency. The coating method is also excellent in production speed.

  After coating, it is preferable to perform heating in order to cause removal of residual solvent, moisture and gas, and improvement of mobility and absorption longwave due to crystallization of the semiconductor material. When annealing is performed at a predetermined temperature during the manufacturing process, a part of the particles is microscopically aggregated or crystallized, and the bulk heterojunction layer can have an appropriate phase separation structure. As a result, the carrier mobility of the bulk heterojunction layer is improved and high efficiency can be obtained.

  The photoelectric conversion part (bulk heterojunction layer) 14 may be composed of a single layer in which the electron acceptor and the electron donor are uniformly mixed, but a plurality of the mixture ratios of the electron acceptor and the electron donor are changed. It may consist of layers. In this case, it can be formed by using a material that can be insolubilized after coating as described above.

(Electron transport layer / hole blocking layer)
Since the organic photoelectric conversion element 10 of the present invention can take out charges generated in the bulk heterojunction layer more efficiently by forming the electron transport layer 18 between the bulk heterojunction layer and the cathode. It is preferable to have this layer.

  As the electron transport layer 18, octaazaporphyrin and a p-type semiconductor perfluoro (perfluoropentacene, perfluorophthalocyanine, etc.) can be used. Similarly, a HOMO of a p-type semiconductor material used for a bulk heterojunction layer. The electron transport layer having a HOMO level deeper than the level is given a hole blocking function having a rectifying effect so that holes generated in the bulk heterojunction layer do not flow to the cathode side. More preferably, a material deeper than the HOMO level of the n-type semiconductor is used as the electron transport layer. Moreover, it is preferable to use a compound with high electron mobility from the characteristic of transporting electrons.

  Such an electron transport layer is also called a hole blocking layer, and it is preferable to use an electron transport layer having such a function. As such a material, compounds represented by the general formulas (1) to (5) in the present invention are preferably used, and among them, compounds in which n01 and n02 are 1 are more preferably used. In addition to the above compounds, phenanthrene compounds such as bathocuproine, n-type semiconductor materials such as naphthalenetetracarboxylic acid anhydride, naphthalenetetracarboxylic acid diimide, perylenetetracarboxylic acid anhydride, perylenetetracarboxylic acid diimide, and titanium oxide, N-type inorganic oxides such as zinc oxide and gallium oxide, and alkali metal compounds such as lithium fluoride, sodium fluoride, and cesium fluoride can be used. A layer made of a single n-type semiconductor material used for the bulk heterojunction layer can also be used.

  The means for forming these layers may be either a vacuum deposition method or a solution coating method, but is preferably a solution coating method.

(Hole transport layer / electron block layer)
In the organic photoelectric conversion element 10 of the present invention, the hole transport layer 17 can be taken out between the bulk heterojunction layer and the anode, and charges generated in the bulk heterojunction layer can be taken out more efficiently. It is preferable to have.

  As a material constituting these layers, for example, as the hole transport layer 17, PEDOT such as trade name BaytronP, polyaniline and its doping material, a cyanide compound described in WO2006 / 019270, etc. Etc. can be used. Note that the hole transport layer having a LUMO level shallower than the LUMO level of the n-type semiconductor material used for the bulk heterojunction layer has a rectifying effect that prevents electrons generated in the bulk heterojunction layer from flowing to the anode side. It has an electronic block function. Such a hole transport layer is also called an electron block layer, and it is preferable to use a hole transport layer having such a function. As such a material, a triarylamine compound described in JP-A-5-271166 or a metal oxide such as molybdenum oxide, nickel oxide, or tungsten oxide can be used. A layer made of a single p-type semiconductor material used for the bulk heterojunction layer can also be used.

  As the material for the hole transport layer, a compound having a partial structure represented by the general formulas (1) to (5) in the present invention can be used, and a compound in which n01 and n02 are 0 is preferable.

  The means for forming these layers may be either a vacuum deposition method or a solution coating method, but is preferably a solution coating method. Forming the coating film in the lower layer before forming the bulk heterojunction layer is preferable because it has the effect of leveling the coating surface and reduces the influence of leakage and the like.

(Other layers)
For the purpose of improving energy conversion efficiency and improving the lifetime of the element, a structure having various intermediate layers in the element may be employed. Examples of the intermediate layer include a hole block layer, an electron block layer, a hole injection layer, an electron injection layer, an exciton block layer, a UV absorption layer, a light reflection layer, and a wavelength conversion layer.

〔electrode〕
The organic photoelectric conversion element of the present invention has at least an anode and a cathode. Further, when a tandem configuration is adopted, the tandem configuration can be achieved by using an intermediate electrode. In the present invention, an electrode through which holes mainly flow is called an anode, and an electrode through which electrons mainly flow is called a cathode.

  Further, because of the function of whether or not there is a light-transmitting property, a light-transmitting electrode may be called a transparent electrode, and a non-light-transmitting electrode may be called a counter electrode. Usually, the anode is a translucent transparent electrode, and the cathode is a non-translucent counter electrode.

(anode)
The anode of the present invention is preferably an electrode that transmits light of 380 to 800 nm. As the material, for example, transparent conductive metal oxides such as indium tin oxide (ITO), SnO ₂ and ZnO, metal thin films such as gold, silver and platinum, metal nanowires and carbon nanotubes can be used.

  Also, a conductive material selected from the group consisting of polypyrrole, polyaniline, polythiophene, polythienylene vinylene, polyazulene, polyisothianaphthene, polycarbazole, polyacetylene, polyphenylene, polyphenylene vinylene, polyacene, polyphenylacetylene, polydiacetylene, and polynaphthalene. A functional polymer can also be used. Further, a plurality of these conductive compounds can be combined to form an anode.

(cathode)
The cathode may be a single layer of a conductive material, but in addition to a conductive material, a resin that holds these may be used in combination. As a conductive material for the cathode, a material having a work function (4 eV or less) metal, alloy, electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like. Among these, from the viewpoint of electron extraction performance and durability against oxidation, etc., a mixture of these metals and a second metal which is a stable metal having a larger work function value than this, for example, a magnesium / silver mixture, magnesium / Aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm.

  If a metal material is used as the conductive material of the cathode, the light coming to the cathode side is reflected and reflected to the first electrode side, and this light can be reused and absorbed again by the photoelectric conversion layer, further improving the photoelectric conversion efficiency. It is preferable.

  Further, the cathode 13 may be a metal (for example, gold, silver, copper, platinum, rhodium, ruthenium, aluminum, magnesium, indium, etc.), a nanoparticle made of carbon, a nanowire, or a nanostructure. A dispersion is preferable because a transparent and highly conductive cathode can be formed by a coating method.

  When the cathode side is made light transmissive, for example, a conductive material suitable for the cathode, such as aluminum and aluminum alloy, silver and silver compound, is formed with a thin film thickness of about 1 to 20 nm, and By providing a film of the conductive light-transmitting material mentioned in the description, a light-transmitting cathode can be obtained.

(Intermediate electrode)
The intermediate electrode material required in the case of the tandem structure as shown in FIG. 3 is preferably a layer using a compound having both transparency and conductivity. Transparent metal oxides such as ITO, AZO, FTO and titanium oxide, very thin metal layers such as Ag, Al and Au, or layers containing nanoparticles / nanowires, conductive polymer materials such as PEDOT: PSS and polyaniline Etc.) can be used.

  In addition, in the hole transport layer and the electron transport layer described above, there is also a combination that works as an intermediate electrode (charge recombination layer) by appropriately combining and laminating, and with such a configuration, the process of forming one layer This is preferable because it can be omitted.

(substrate)
When light that is photoelectrically converted enters from the substrate side, the substrate is preferably a member that can transmit the light that is photoelectrically converted, that is, a member that is transparent to the wavelength of the light to be photoelectrically converted. As the substrate, for example, a glass substrate, a resin substrate and the like are preferably mentioned, but it is desirable to use a transparent resin film from the viewpoint of light weight and flexibility. There is no restriction | limiting in particular in the transparent resin film which can be preferably used as a transparent substrate by this invention, The material, a shape, a structure, thickness, etc. can be suitably selected from well-known things. For example, polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) modified polyester, polyethylene (PE) resin film, polypropylene (PP) resin film, polystyrene resin film, polyolefin resins such as cyclic olefin resin Film, vinyl resin film such as polyvinyl chloride, polyvinylidene chloride, polyether ether ketone (PEEK) resin film, polysulfone (PSF) resin film, polyether sulfone (PES) resin film, polycarbonate (PC) resin film, A polyamide resin film, a polyimide resin film, an acrylic resin film, a triacetyl cellulose (TAC) resin film, and the like can be given. If the resin film transmittance of 80% or more at ~800nm), can be preferably applied to a transparent resin film according to the present invention. Among these, from the viewpoint of transparency, heat resistance, ease of handling, strength and cost, it is preferably a biaxially stretched polyethylene terephthalate film, a biaxially stretched polyethylene naphthalate film, a polyethersulfone film, or a polycarbonate film, and biaxially stretched. More preferred are polyethylene terephthalate films and biaxially stretched polyethylene naphthalate films.

  The transparent substrate used in the present invention can be subjected to a surface treatment or an easy adhesion layer in order to ensure the wettability and adhesiveness of the coating solution. A conventionally well-known technique can be used about a surface treatment or an easily bonding layer. For example, the surface treatment includes surface activation treatment such as corona discharge treatment, flame treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, active plasma treatment, and laser treatment. Examples of the easy adhesion layer include polyester, polyamide, polyurethane, vinyl copolymer, butadiene copolymer, acrylic copolymer, vinylidene copolymer, and epoxy copolymer.

  Further, for the purpose of suppressing the permeation of oxygen and water vapor, a barrier coat layer may be formed in advance on the transparent substrate, or a hard coat layer may be formed in advance on the opposite side to which the transparent conductive layer is transferred. Good.

(Optical function layer)
The organic photoelectric conversion element of the present invention may have various optical functional layers for the purpose of more efficient reception of sunlight. As the optical functional layer, for example, a light condensing layer such as an antireflection film or a microlens array, a light diffusion layer that can scatter the light reflected by the cathode and enter the power generation layer again may be provided. .

  Various known antireflection layers can be provided as the antireflection layer. For example, when the transparent resin film is a biaxially stretched polyethylene terephthalate film, the refractive index of the easy adhesion layer adjacent to the film is 1.57. It is more preferable to set it to ˜1.63 because the interface reflection between the film substrate and the easy adhesion layer can be reduced and the transmittance can be improved. The method for adjusting the refractive index can be carried out by appropriately adjusting the ratio of the oxide sol having a relatively high refractive index such as tin oxide sol or cerium oxide sol and the binder resin. The easy adhesion layer may be a single layer, but may be composed of two or more layers in order to improve adhesion.

  As the condensing layer, for example, it is processed so as to provide a structure on the microlens array on the sunlight receiving side of the support substrate, or the amount of light received from a specific direction is increased by combining with a so-called condensing sheet. Conversely, the incident angle dependency of sunlight can be reduced.

  As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  Examples of the light scattering layer include various antiglare layers, layers in which nanoparticles or nanowires such as metals or various inorganic oxides are dispersed in a colorless and transparent polymer, and the like.

(Patterning)
The method and process for patterning the electrode, the power generation layer, the hole transport layer, the electron transport layer, and the like according to the present invention are not particularly limited, and known methods can be appropriately applied.

  If it is a soluble material such as a bulk heterojunction layer or a transport layer, only unnecessary portions may be wiped after the entire surface of die coating, dip coating, etc., or direct patterning at the time of coating using a method such as an ink jet method or screen printing. May be.

  In the case of an insoluble material such as an electrode material, the electrode can be patterned by a known method such as mask vapor deposition during vacuum deposition or etching or lift-off. Alternatively, the pattern may be formed by transferring a pattern formed on another substrate.

(Sealing)
Moreover, since the produced organic photoelectric conversion element is not deteriorated by oxygen, moisture, or the like in the environment, it is preferable to seal not only the organic photoelectric conversion element but also an organic electroluminescence element by a known method. For example, a method of sealing a cap made of aluminum or glass by bonding with an adhesive, a plastic film on which a gas barrier layer such as aluminum, silicon oxide, or aluminum oxide is formed and an organic photoelectric conversion element are pasted with an adhesive. Method, spin coating of organic polymer material (polyvinyl alcohol, etc.) with high gas barrier property, inorganic thin film (silicon oxide, aluminum oxide, etc.) or organic film (parylene etc.) with high gas barrier property are deposited under vacuum Examples thereof include a method and a method of laminating these in a composite manner.

[Optical sensor array]
Next, an optical sensor array to which the bulk heterojunction type organic photoelectric conversion element described above is applied will be described in detail. The optical sensor array is produced by arranging the photoelectric conversion elements in a fine pixel form by utilizing the fact that the bulk heterojunction type organic photoelectric conversion elements generate a current upon receiving light, and projected onto the optical sensor array. A sensor having an effect of converting an image into an electrical signal.

  FIG. 4 is a diagram showing the configuration of the photosensor array. 4A is a top view, and FIG. 4B is a cross-sectional view taken along the line A-A ′ of FIG.

  In FIG. 4, an optical sensor array 20 is paired with an anode 22 as a lower electrode, a photoelectric conversion unit 24 that converts light energy into electric energy, and an anode 22 on a substrate 21 as a holding member. The cathode 23 is sequentially laminated. The photoelectric conversion unit 24 includes two layers, a photoelectric conversion layer 24b having a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are uniformly mixed, and a buffer layer 24a. In the example shown in FIG. 4, six bulk heterojunction type organic photoelectric conversion elements are formed.

  The substrate 21, the anode 22, the photoelectric conversion layer 24b, and the cathode 23 have the same configuration and role as the anode 12, the photoelectric conversion unit 14, and the cathode 13 in the bulk heterojunction photoelectric conversion element 10 described above.

  For example, glass is used for the substrate 21, ITO is used for the anode 22, and aluminum is used for the cathode 23, for example. For example, the BP-1 precursor is used for the p-type semiconductor material of the photoelectric conversion layer 24b, and for example, the exemplified compound 13 is used for the n-type semiconductor material. The buffer layer 24a is made of PEDOT (poly-3,4-ethylenedioxythiophene) -PSS (polystyrene sulfonic acid) conductive polymer (trade name BaytronP, manufactured by Stark Vitec). Such an optical sensor array 20 was manufactured as follows.

  An ITO film was formed on the glass substrate by sputtering and processed into a predetermined pattern shape by photolithography. The thickness of the glass substrate was 0.7 mm, the thickness of the ITO film was 200 nm, and the measurement area (light receiving area) of the ITO film after photolithography was 0.5 mm × 0.5 mm. Next, a PEDOT-PSS film was formed on the glass substrate 21 by spin coating (conditions: rotational speed = 1000 rpm, filter diameter = 1.2 μm). Thereafter, the substrate was heated in an oven at 140 ° C. for 10 minutes and dried. The thickness of the PEDOT-PSS film after drying was 30 nm.

  Next, a 1: 4 mixed film of the compound 5 of the present invention and PCBM was formed on the PEDOT-PSS film by a spin coating method (conditions: rotational speed = 3300 rpm, filter diameter = 0.8 μm). In this spin coating, the compound 5 and PCBM of the present invention were mixed in a chlorobenzene solvent at 1: 4, and a mixture obtained by stirring (5 minutes) was used. After forming the mixed film of P3HT and PCBM, annealing was performed by heating in an oven at 180 ° C. for 30 minutes in a nitrogen gas atmosphere. The thickness of the mixed film of Compound 5 and PCBM of the present invention after the annealing treatment was 70 nm.

  Then, using a metal mask having a predetermined pattern opening, 5 nm of the compound 16 of the present invention is deposited as an electron transport layer on the mixed film of the compound 5 and PCBM of the present invention, and then an aluminum layer as a cathode is deposited. It was formed by the method (thickness = 10 nm). Thereafter, 1 μm of PVA (polyvinyl alcohol) was formed by spin coating and baked at 150 ° C. to prepare a passivation layer (not shown). The optical sensor array 20 was produced as described above.

  When this photosensor array 20 was irradiated with light having a predetermined pattern, it was confirmed that the photocurrent was detected only from the cells that were exposed to light and functioned as a photosensor.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

Example 1 (use as a hole blocking layer)
[Production of organic photoelectric conversion element]
(Preparation of organic photoelectric conversion element 1)
The transparent electrode patterned on the glass substrate was cleaned in the order of ultrasonic cleaning with surfactant and ultrapure water, followed by ultrasonic cleaning with ultrapure water, dried with nitrogen blow, and finally UV ozone cleaning. .

  On this transparent substrate, Baytron P4083 (manufactured by Starck Vitec), which is a conductive polymer, was spin-coated with a film thickness of 30 nm, and then dried by heating at 140 ° C. in the air for 10 minutes.

  After this, the substrate was brought into the glove box and worked under a nitrogen atmosphere. First, the substrate was heat-treated at 140 ° C. for 3 minutes in a nitrogen atmosphere. A solution is prepared by dissolving 1.5% by mass of Plexcore OS2100 Plexcore OS2100 as a p-type semiconductor material and 1.5% by mass of Frontier Carbon E100 (PCBM) as an n-type semiconductor material in chlorobenzene. While being filtered through a 45 μm filter, spin coating was performed at 500 rpm for 60 seconds, then at 2200 rpm for 1 second, and left at room temperature for 30 minutes.

  Next, a solution in which batocuproine (BCP) manufactured by Aldrich was mixed with 2,2,3,3-tetrafluoro-1-propanol at a ratio of 0.5 mass% was spin-coated at 1500 rpm, and a hole block having a thickness of 10 nm was formed. A layer was formed.

Next, the substrate on which the series of organic layers was formed was placed in a vacuum deposition apparatus without being exposed to the atmosphere. The element was set so that the shadow mask with a width of 2 mm was orthogonal to the transparent electrode, and the inside of the vacuum deposition apparatus was depressurized to 10 ⁻³ Pa or less, and then 100 nm of Al was deposited. Finally, the heating for 30 minutes was performed at 120 degreeC, and the comparative organic photoelectric conversion element 1 was obtained. The vapor deposition rate was 2 nm / second, and the size was 2 mm square.

  The obtained organic photoelectric conversion element 1 was taken out into the atmosphere after sealing using an aluminum cap and a UV curable resin (manufactured by Nagase ChemteX Corporation, UV RESIN XNR5570-B1) in a nitrogen atmosphere.

(Preparation of organic photoelectric conversion element 2)
In preparation of the organic photoelectric conversion element 1, instead of a 0.5% 2,2,3,3-tetrafluoro-1-propanol solution of batocuproine as the hole blocking layer, Ti-isopropoxide was added to ethanol at 25 mmol / l. After the electrode portion was masked and spin-coated at 2000 rpm, it was taken out into the atmosphere and left for 60 minutes to hydrolyze Ti-isopropoxide to obtain a film thickness of 10 nm. A comparative organic photoelectric conversion element 2 was produced in the same manner except that a TiOx layer was formed and a hole blocking layer was formed.

(Preparation of organic photoelectric conversion elements 3 to 12)
In the production of the organic photoelectric conversion device 1, the organic photoelectric conversion devices 3 to 12 of the present invention were produced in the same manner except that the batocuproine of the hole blocking layer was changed to the compound of the present invention shown in Table 1 below.

[Evaluation of organic photoelectric conversion elements]
About the obtained organic photoelectric conversion element, the following conversion efficiency, a fill factor, and durability were evaluated.

(Conversion efficiency and fill factor)
Photoelectric conversion elements prepared above, was irradiated with light having an intensity of 100 mW / cm ² solar simulator (AM1.5G filter), a superposed mask in which the effective area 4.0 mm ² on the light receiving portion, the short circuit current density Jsc ( The four light-receiving portions formed on the same element were measured for mA / cm ² ), open-circuit voltage Voc (V), and fill factor (fill factor) FF, and the average value was obtained. Further, energy conversion efficiency η (%) was obtained from Jsc, Voc, and FF according to Equation 1.

Formula 1 Jsc (mA / cm ² ) × Voc (V) × FF = η (%)
(durability)
A solar simulator (AM1.5G) was irradiated at an irradiation intensity of 100 mW / cm ² , voltage-current characteristics were measured, and initial conversion efficiency was measured. Furthermore, assuming that the initial conversion efficiency at this time is 100, the conversion efficiency after 100 hours of irradiation with an irradiation intensity of 100 mW / cm ² with the resistance connected between the anode and the cathode is evaluated, and the relative reduction efficiency according to Equation 2 Was calculated.

Formula 2 Relative reduction efficiency (%) = (1−conversion efficiency after exposure / conversion efficiency before exposure) × 100
The evaluation results are shown in Table 1.

  From Table 1, it can be seen that the organic photoelectric conversion element of the present invention using the compound of the present invention for the hole blocking layer has improved curve factor and high conversion efficiency. Moreover, it turns out that relative fall efficiency is low and durability is high.

Example 2 (Use as p-type semiconductor layer)
[Production of organic photoelectric conversion element]
(Preparation of organic photoelectric conversion element 21)
As a comparative p-type semiconductor material, Comparative Compound 1 was synthesized with reference to Non-Patent Document 3. After the synthesis, reprecipitation was performed with a methanol: pure water = 10: 1 solution, followed by Soxhlet extraction in the order of acetone, hexane, dichloromethane, and chloroform, and the chloroform-dissolved component was again made into a methanol: pure water = 10: 1 solution. Purification was performed by reprecipitation. The number average molecular weight of Comparative Compound 1 was 37000.

  Subsequently, after providing the PEDOT: PSS layer in the same manner as in the organic photoelectric conversion element 1 of Example 1, the substrate was similarly brought into a glove box and operated in a nitrogen atmosphere. First, the substrate was heat-treated at 140 ° C. for 3 minutes in a nitrogen atmosphere. A liquid in which 0.5% by mass of the comparative p-type semiconductor material 1 as a p-type semiconductor material and 2.0% by mass of Frontier Carbon E100 (PCBM) as an n-type semiconductor material was dissolved in chlorobenzene was prepared. The solution was spin-coated at 2000 rpm for 60 seconds while being filtered through a 45 μm filter, heated at 50 ° C. for 10 minutes, and then allowed to stand at room temperature for 12 hours.

Next, the substrate on which the series of organic layers was formed was placed in a vacuum deposition apparatus without being exposed to the atmosphere. The element was set so that the shadow mask with a width of 2 mm was orthogonal to the transparent electrode, and the inside of the vacuum deposition apparatus was depressurized to 10 ⁻³ Pa or less, and then 0.6 nm of lithium fluoride and 100 nm of Al were deposited. Finally, the heating for 30 minutes was performed at 120 degreeC, and the comparative organic photoelectric conversion element 11 was obtained. The vapor deposition rate was 2 nm / second, and the size was 2 mm square.

  The obtained organic photoelectric conversion element 1 was taken out into the atmosphere after sealing using an aluminum cap and a UV curable resin (manufactured by Nagase ChemteX Corporation, UV RESIN XNR5570-B1) in a nitrogen atmosphere.

(Preparation of organic photoelectric conversion elements 22 to 34)
In the production of the organic photoelectric conversion element 21, the organic photoelectric conversion of the present invention was similarly performed except that the p-type semiconductor material was changed to the compound of the present invention described in Table 2 below instead of the comparative p-type semiconductor material 1. Elements 22 to 34 were produced. When the p-type semiconductor material is a polymer, the same purification as that of the comparative p-type semiconductor material 1 is performed. When the p-type semiconductor material is a low-molecular material, purification is performed using silica gel column chromatography and gel permeation chromatography. . The number average molecular weight of the compound used for the organic photoelectric conversion elements 22 to 34 was 7000 to 8000.

(Preparation of organic photoelectric conversion element 35)
Furthermore, after forming a bulk heterojunction layer similarly to the organic photoelectric conversion element 29 as the organic photoelectric conversion element 35 of this invention, the said exemplary compound 12 is 2,2,3,3- in the ratio of 0.5 mass%. A solution mixed with tetrafluoro-1-propanol was spin-coated at 1500 rpm to form a 10 nm-thick hole blocking layer. Thereafter, the organic photoelectric conversion element 35 was produced in the same manner as the organic photoelectric conversion element 29.

[Evaluation of organic photoelectric conversion elements]
About the obtained organic photoelectric conversion element, it carried out similarly to Example 1, and evaluated open circuit voltage, conversion efficiency, and relative fall efficiency.

  The evaluation results are shown in Table 2.

  From Table 2, it is clear that the organic photoelectric conversion element of the present invention using the compound of the present invention for the p-type semiconductor layer can obtain a high open-circuit voltage and photoelectric conversion efficiency. Moreover, it turns out that higher photoelectric conversion efficiency is obtained by providing the hole block layer which consists of a compound of this invention.

DESCRIPTION OF SYMBOLS 10 Bulk heterojunction type organic photoelectric conversion element 11 Substrate 12 Anode 13 Cathode 14 Photoelectric conversion part (bulk heterojunction layer)
14p p layer 14i i layer 14n n layer 14 'first photoelectric conversion part 15 charge recombination layer 16 second photoelectric conversion part 17 hole transport layer 18 electron transport layer 20 photosensor array 21 substrate 22 anode 23 cathode 24 photoelectric Conversion unit 24a Buffer layer 24b Photoelectric conversion layer

Claims (14)

An organic photoelectric conversion element having a cathode, an anode, and a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are mixed, and is represented by at least the following general formula (1) between the cathode and the anode. An organic photoelectric conversion device comprising a layer containing a compound having a partial structure. However, the case where the compound having the partial structure represented by the following general formula (1) is the following compound (3) is excluded.

(In the formula, n01 represents 1 and R ¹ represents a substituent.)

The organic photoelectric conversion device according to claim 1, wherein the compound having a partial structure represented by the general formula (1) is a compound having a partial structure represented by the following general formula (2).

(In the formula, n01 represents 1 and R ¹ represents a substituent.) An organic photoelectric conversion element having a cathode, an anode, and a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are mixed, and is represented by at least the following general formula (1) between the cathode and the anode. An organic photoelectric conversion device comprising a layer containing a compound having a partial structure, wherein the layer is the bulk heterojunction layer.

(In the formula, n01 represents 0 or 1, R ¹ Represents a substituent. ) The organic photoelectric conversion device according to claim 3, wherein the compound having a partial structure represented by the general formula (1) is a compound having a partial structure represented by the following general formula (2).

(In the formula, n01 represents 0 or 1, R ¹ Represents a substituent. ) An organic photoelectric conversion element having a cathode, an anode, and a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are mixed, and is represented by at least the following general formula (3) between the cathode and the anode. organic photoelectric conversion element characterized by having a layer containing a compound having a partial structure.

(In the formula, n01 and n02 each represent 0 or 1, and R ¹ and R ² each represent a substituent.) The organic photoelectric conversion device according to claim 5 , wherein the compound having a partial structure represented by the general formula (3) is a compound having a partial structure represented by the following general formula (4).

(In the formula, n01 and n02 each represent 0 or 1, and R ¹ and R ² each represent a substituent.) The organic photoelectric conversion device according to claim 6 , wherein the compound having a partial structure represented by the general formula (4) is a compound having a partial structure represented by the following general formula (5).

(In the formula, n01 and n02 each represent 0 or 1, and R ¹ and R ² each represent a substituent.) The formulas (1) to (5), an organic photoelectric conversion device according to any one of claims 3-7, characterized in that n01 and n02 are 1. The organic photoelectric conversion device according to any one of claims 1 to 8 , wherein the compound having a partial structure represented by the general formula (1) to the general formula (5) is a low molecular compound. . The layer containing a compound having a partial structure represented by the general formula (1) to the general formula (5) exists between the bulk heterojunction layer and the cathode . The organic photoelectric conversion element according to any one of 2, 5 to 9 . Layer containing a compound having a partial structure represented by formulas (1) to (5) of claim 1, 2,5 to 9, characterized in that the heterojunction layer to the bulk The organic photoelectric conversion element of any one of Claims 1. Layer containing a compound having a partial structure represented by formulas (1) to (5), in any one of claims 1 to 11, characterized in that it is produced by a solution coating method The organic photoelectric conversion element as described. Solar cell characterized by comprising the organic photoelectric conversion device according to any one of claims 1 to 12. Photosensor array organic photoelectric conversion device according, characterized in that are arranged in a array form in any one of claims 1 to 12.

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