JP2012182439A - Organic photoelectric conversion element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic photoelectric conversion element having two or more active layers and a conjugate, the open end voltage (Voc) of which is sufficiently high when compared with an organic photoelectric conversion element having one active layer.SOLUTION: The organic photoelectric conversion element is composed by laminating, between a pair of electrodes, a plurality of active layers and conjugates interposed between the active layers. The conjugate has a plurality of layers including an electron transport layer and a hole transport layer, and the electron transport layer is formed by applying a coating liquid containing an electron transport material and a solvent represented by formula (1a) or a solvent represented by formula (1b) onto a layer underlying the electron transport layer. (In the formulae, n represents an integer of 2-5, and R represents an alkyl group of 1-10C).

Description

  The present invention relates to an organic photoelectric conversion element.

  In recent years, organic photoelectric conversion elements (such as organic solar cells and optical sensors) using light energy have attracted attention. Since a high electromotive force can be obtained by laminating a plurality of active layers, an element having a multi-junction structure in which two or more active layers are laminated, represented by a tandem structure, is expected. In an organic photoelectric conversion element having a multi-junction structure, not only an organic photoelectric conversion element in which active layers are simply stacked, but also an organic photoelectric conversion element in which a bonded body is provided between active layers has been studied.

  The joined body is usually formed by laminating a plurality of layers such as an electron transport layer, a charge recombination layer, and a hole transport layer. As an organic photoelectric conversion element having a multi-junction structure, there are two active layers, an electron transport layer made of zinc oxide nanoparticles between the active layers, and neutralized PEDOT: PSS {poly (3,4). An organic photoelectric conversion element having a joined body including a hole transport layer formed of a mixture of ethylenedioxythiophene (PEDOT) and poly (4-styrenesulfonic acid) (PSS) has been proposed. The electron transport layer contained in the joined body of the organic photoelectric conversion element is formed by applying a liquid containing zinc oxide nanoparticles and acetone on the active layer (Non-Patent Document 1).

Applied Physics Letters, 2007, Vol. 90, p. 143512

  However, the above-described organic photoelectric conversion element having two active layers and a bonded body is not sufficiently improved in open-circuit voltage (Voc) compared to an organic photoelectric conversion element having one active layer. There are challenges.

  An object of the present invention is to provide an organic photoelectric conversion element having two or more active layers and a joined body, which has a sufficiently high open-circuit voltage (Voc) as compared with an organic photoelectric conversion element having one active layer. Is to provide.

（１ａ） （１ｂ）
〔式中、ｎは、２〜５の整数を表し、Ｒは、炭素数１〜１０のアルキル基を表す。〕 That is, the first aspect of the present invention is an organic photoelectric conversion element constituted by laminating a plurality of active layers and a joined body positioned between the active layers between a pair of electrodes,
The joined body contains a plurality of layers including an electron transport layer and a hole transport layer,
By applying the coating liquid containing the electron transporting material and the solvent represented by the formula (1a) or the solvent represented by the formula (1b) on the layer below the electron transporting layer. An organic photoelectric conversion element to be formed is provided.

(1a) (1b)
[Wherein, n represents an integer of 2 to 5, and R represents an alkyl group having 1 to 10 carbon atoms. ]

  Secondly, the present invention provides the organic photoelectric conversion element, wherein the electron transporting material includes particles made of zinc oxide.

  In the present invention, thirdly, the hole transport layer is formed by coating a coating solution containing a hole transport material and a solvent and having a pH of 3 to 9 on a layer below the hole transport layer. The organic photoelectric conversion element is provided.

  Fourthly, the present invention provides the organic photoelectric conversion element, wherein the active layer contains a conjugated polymer compound and a fullerene derivative.

（１ａ） （１ｂ）
〔式中、ｎは、２〜５の整数を表し、Ｒは、炭素数１〜１０のアルキル基を表す。〕 Fifth, the present invention comprises a plurality of active layers and a joined body containing a plurality of layers located between the active layers and including an electron transport layer and a hole transport layer, laminated between a pair of electrodes. A method for producing an organic photoelectric conversion element comprising:
The electron transport layer is formed by applying a coating liquid containing an electron transport material and a solvent represented by the formula (1a) or a solvent represented by the formula (1b) on a layer below the electron transport layer. Provided is a method for producing an organic photoelectric conversion element.

(1a) (1b)
[Wherein, n represents an integer of 2 to 5, and R represents an alkyl group having 1 to 10 carbon atoms. ]

  Sixthly, in the present invention, the hole transport layer is formed by applying a coating solution containing a hole transport material and a solvent and having a pH of 3 to 9 on a layer below the hole transport layer. The manufacturing method is provided.

  According to the present invention, an organic photoelectric conversion element having two or more active layers and a bonded body has a sufficiently high open-circuit voltage (Voc) as compared with an organic photoelectric conversion element having one active layer. The present invention is extremely useful because it is obtained.

  Hereinafter, the present invention will be described in detail.

<Organic photoelectric conversion element>
The organic photoelectric conversion element of the present invention is configured by laminating a plurality of active layers and a joined body positioned between the active layers between a pair of electrodes, and the joined body includes an electron transport layer and a hole transport layer. A coating solution containing the electron transporting material and the solvent represented by the formula (1a) or the solvent represented by the formula (1b) on the layer below the electron transporting layer. It is formed by coating.

An example of the element structure of the organic photoelectric conversion element of this invention is shown.
(A) Anode / active layer / junction / active layer / cathode (b) anode / (repeating unit) m / active layer / cathode (the symbol “/” is laminated with adjacent layers sandwiching the symbol “/”) The same applies hereinafter.) In (b), “(repeat unit)” represents a laminate of the active layer and the bonded body (active layer / bonded body), and the symbol “m” represents one or more. An integer is represented, and “(repeat unit) m” represents a laminated body in which m laminated bodies (active layer / joined body) are laminated. An electron transport layer may be provided between the cathode and the active layer, and a hole transport layer may be provided between the active layer and the anode.

  The element (a) is an element having a tandem structure, and the element (b) is an element having a multi-junction structure in which (m + 1) active layers are stacked via a bonded body. Here, a multi-junction structure in which two active layers are laminated via a joined body is referred to as a tandem structure.

The joined body is formed by stacking a plurality of layers, and includes at least an electron transport layer and a hole transport layer. The joined body is configured, for example, by laminating an electron transport layer, a charge recombination layer, and a hole transport layer in this order.
In addition, the joined body may be composed of only an electron transport layer and a hole transport layer, or may have a layer other than the three layers described above. In the joined body, of the electron transport layer and the hole transport layer, the electron transport layer is disposed on the anode side, and the hole transport layer is disposed on the cathode side.

  The organic photoelectric conversion element is usually formed by sequentially laminating a pair of electrodes, an active layer, and a bonded body in the order described below on a substrate.

  For example, the element (a) can be formed by sequentially laminating an anode, an active layer, a bonded body, an active layer, and a cathode in this order on a substrate. Similarly to the element (a), the element (b) also has an anode, an active layer, a bonded body, an active layer, a bonded body, ... (repetition of the active layer and the bonded body) on the substrate. -It can form by laminating | stacking an active layer and a cathode sequentially in this order.

  The substrate that the organic photoelectric conversion element of the present invention may have is not particularly limited as long as it does not chemically change when an electrode is formed and when an organic layer is formed. Examples of the material for the substrate include glass, plastic, polymer film, and silicon. When an opaque substrate is used, the opposite electrode (that is, the electrode far from the substrate) is preferably transparent or translucent. Hereafter, each component of an organic photoelectric conversion element and those manufacturing methods are demonstrated.

（１ａ） （１ｂ） (Electron transport layer)
The electron transport layer is formed by applying a coating liquid containing an electron transport material and a solvent represented by the formula (1a) or a solvent represented by the formula (1b) on a layer below the electron transport layer. Is done. In the present invention, the coating solution may not be a solution, but may be a dispersion such as an emulsion (emulsion) or a suspension (suspension).

(1a) (1b)

  In formula (1a) and formula (1b), n represents an integer of 2 to 5, and R represents an alkyl group having 1 to 10 carbon atoms.

Examples of the solvent represented by the formula (1a) include methanol, ethanol, 1-propanol, 2-propanol, butanol and the like.
Examples of the solvent represented by the formula (1b) include ethylene glycol monobutyl ether, propylene glycol monomethyl ether, methoxybutanol and the like.

  Examples of the electron transporting material include zinc oxide, titanium oxide, zirconium oxide, tin oxide, indium oxide, ITO (indium tin oxide), FTO (fluorine-doped tin oxide), GZO (gallium-doped zinc oxide), and ATO ( Antimony-doped tin oxide) and AZO (aluminum-doped zinc oxide). Among the electron transporting materials, it is preferable to use zinc oxide nanoparticles. The electron transport layer is preferably made of an electron transporting material containing zinc oxide nanoparticles, and more preferably made of only zinc oxide nanoparticles.

  Functions of the electron transport layer include a function to increase the efficiency of electron injection into the charge recombination layer, a function to prevent the injection of holes from the active layer, a function to increase the electron transport capability, and a function to suppress deterioration of the active layer. Etc.

  When zinc oxide is used as the electron transporting material, a dispersion liquid in which zinc oxide is dispersed in the solvent represented by the formula (1a) or the solvent represented by the formula (1b) is used as a coating liquid. The electron transport layer is formed by coating on the layer below the electron transport layer. As zinc oxide, fine zinc oxide is preferable, zinc oxide having an average particle size of 10 μm or less is more preferable, and zinc oxide having an average particle size of 1 μm or less is more preferable. From the viewpoint of increasing the photoelectric conversion efficiency of the organic photoelectric conversion element, the average particle diameter of zinc oxide is preferably 100 nm or less, and more preferably 50 nm or less. From the viewpoint of improving the dispersibility of zinc oxide in a solvent, the average particle diameter of zinc oxide is preferably 30 nm or less.

  The electrical conductivity of zinc oxide is preferably 0.01 mS / cm or more, and more preferably 1 mS / cm or more. From the viewpoint of increasing the photoelectric conversion efficiency of the organic photoelectric conversion element, the electric conductivity of zinc oxide is preferably 10 mS / cm or more.

  When the joined body is composed of an electron transport layer, a charge recombination layer, and a hole transport layer and has an electron transport layer on the charge recombination layer, the electron transport layer is coated with the coating liquid described above on the charge recombination layer Furthermore, it is formed by removing the solvent represented by the formula (1a) or the solvent represented by the formula (1b). When the joined body is composed of an electron transport layer and a hole transport layer, and the electron transport layer is formed on the active layer, the electron transport layer is coated with the above-described coating solution on the active layer, and the formula ( It is formed by removing the solvent represented by 1a) or the solvent represented by formula (1b). Removal of the solvent represented by the formula (1a) or the solvent represented by the formula (1b) is performed, for example, by leaving it for a predetermined time in the air or under reduced pressure, and heat treatment is performed as necessary. Is done.

  As a method of applying the coating solution on the active layer or the charge recombination layer, spin coating method, casting method, micro gravure coating method, gravure coating method, bar coating method, roll coating method, wire bar coating method, dip coating Examples thereof include coating methods such as a coating method, a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, an inkjet printing method, a dispenser printing method, a nozzle coating method, and a capillary coating method. Among the coating methods, spin coating, flexographic printing, ink jet printing, and dispenser printing are preferable. The thickness of the electron transport layer is preferably 1 nm to 100 μm, more preferably 2 nm to 1000 nm, still more preferably 5 nm to 500 nm, and particularly preferably 20 nm to 200 nm.

(Hole transport layer)
When the joined body of the present invention includes an electron transport layer, a charge recombination layer, and a hole transport layer in this order, the hole transport layer is formed after forming the electron transport layer and the charge recombination layer, When forming the hole transport layer, it is desirable not to damage the electron transport layer and the charge recombination layer previously formed. In addition, when the joined body of the present invention includes the electron transport layer and the hole transport layer in this order, the hole transport layer is formed after the electron transport layer is formed, so that the hole transport layer is formed. At this time, it is desirable not to damage the previously formed electron transport layer. By setting the pH of the coating liquid containing the hole transporting material and the solvent to 3 to 9, and applying the coating liquid on the electron transport layer or the charge recombination layer to form the hole transport layer, Since no damage is caused to each layer of the joined body excluding the transport layer, it is possible to produce an organic photoelectric conversion element with reduced damage to the joined body, and thus to produce an organic photoelectric conversion element with high photoelectric conversion efficiency. Can do.

  The function of the hole transport layer is to increase the efficiency of hole injection into the charge recombination layer, to prevent the injection of electrons from the active layer, to increase the hole transport capability, and to deposit the charge recombination layer. The function of improving the flatness of the charge recombination layer when the charge recombination layer is produced by the method, and when the charge recombination layer is produced by the coating method, the active layer is protected from erosion by the coating liquid for forming the charge recombination layer The function, the function which suppresses degradation of an active layer, etc. are mentioned.

As the hole transport material, for example, a polymer compound having a function of transporting holes can be given. Examples of the polymer compound having a function of transporting holes include a polymer compound containing a thiophene diyl group, a polymer compound containing an aniline diyl group, and a polymer compound containing a pyrrole diyl group. Among polymer compounds that exhibit a function of transporting holes, a polymer compound having high conductivity is preferable. The conductivity of the polymer compound having high conductivity is usually 10 ⁻⁵ to 10 ⁵ S / cm, preferably 10 ⁻³ to 10 ⁴ S / cm.

  Examples of the polymer compound having a function of transporting holes include PEDOT / PSS {poly (3,4-ethylenedioxythiophene) (PEDOT) and poly (4-styrenesulfone) neutralized by adding a base or the like. Acid) (mixture with (PSS)) is preferred.

  The polymer compound showing the function of transporting holes may have an acid group such as a sulfonic acid group. Examples of the polymer compound having an acid group include poly (thiophene) having an acid group and poly (aniline) having an acid group. The poly (thiophene) having an acid group and the poly (aniline) having an acid group may further have a substituent other than the acid group.

  The hole transport layer may contain another polymer compound as a binder in addition to the polymer compound having a function of transporting holes. Examples of the binder include polystyrene sulfonic acid, polyvinyl phenol, novolac resin, and polyvinyl alcohol.

  The coating liquid used when forming the hole transport layer by a coating method includes a material to be the hole transport layer and a solvent. When zinc oxide is used as the electron transporting material, the coating solution preferably has a pH of 3 to 9, more preferably 6 to 8, from the viewpoint of not damaging the zinc oxide. Examples of the solvent contained in the coating solution include water and alcohol. Specific examples of the alcohol include methanol, ethanol, isopropanol, butanol, ethylene glycol, propylene glycol, butoxyethanol, and methoxybutanol. Moreover, you may use the liquid mixture containing 2 or more types of above-mentioned solvent as a solvent of a coating liquid.

  For coating film formation, spin coating method, casting method, micro gravure coating method, gravure coating method, bar coating method, roll coating method, wire bar coating method, dip coating method, spray coating method, screen printing method, flexographic method Coating methods such as a printing method, an offset printing method, an ink jet printing method, a dispenser printing method, a nozzle coating method, and a capillary coating method can be used. Among the coating methods, it is preferable to use a spin coating method, a flexographic printing method, an ink jet printing method, or a dispenser printing method.

(Charge recombination layer)
The charge recombination layer is not necessarily provided in the joined body, but is preferably provided between the electron transport layer and the hole transport layer for ohmic junction between the electron transport layer and the hole transport layer. . The charge recombination layer is preferably formed in a state where a plurality of fine particles are aggregated or in a thin film shape.

  The charge recombination layer typically includes a metal. The charge recombination layer may contain a metal oxide or a metal halide. However, when the weight of the metal is 100, the total of the weight of the metal oxide and the weight of the metal halide is 10. It is preferable that it is as follows, and it is more preferable that it consists essentially of a metal. The metals include lithium, beryllium, sodium, magnesium, aluminum, potassium, calcium, scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, rubidium, strontium, yttrium, zirconium, Niobium, molybdenum, ruthenium, rhodium, palladium, silver, cadmium, indium, tin, antimony, cesium, barium, lanthanum, hafnium, tantalum, tungsten, rhenium, osmium, iridium, platinum, gold, mercury, thallium, lead, bismuth, A lanthanide etc. are mentioned. Further, an alloy of these metals, graphite, or an intercalation compound between these metals and graphite can be used for the charge recombination layer. Among metals, aluminium, magnesium, titanium, chromium, iron, nickel, copper, zinc, gallium, zirconium, molybdenum, silver, indium, tin, and gold are preferable.

  The method for forming the charge recombination layer is not particularly limited, and examples thereof include a vacuum deposition method from powder.

(Active layer)
The active layer may be, for example, a laminate in which a first layer containing an electron-accepting compound and a second layer containing an electron-donating compound are in contact with each other. A single layer containing an electron donating compound may be used.

One of the electron-donating compound and the electron-accepting compound is preferably a polymer compound, and as an electron-donating compound or an electron-accepting compound, one kind of polymer compound may be contained alone, or two or more kinds The high molecular compound may be included. From the viewpoint of including many heterojunction interfaces, the electron-accepting compound is preferably a fullerene derivative. Among these, it is preferable that the active layer contains a conjugated polymer compound and a fullerene derivative.
As the active layer, for example, an organic thin film containing a conjugated polymer compound and a fullerene derivative can be used.
When the active layer contains a fullerene derivative and an electron donating compound, the weight of the fullerene derivative contained in the active layer is preferably 10 to 1000 parts by weight with respect to 100 parts by weight of the electron donating compound, More preferably, it is 500 parts by weight.

  The electron-accepting compound suitably used for the organic photoelectric conversion element is such that the HOMO energy of the electron-accepting compound is higher than the HOMO energy of the electron-donating compound, and the LUMO energy of the electron-accepting compound is LUMO of the electron-donating compound. Higher than energy.

  The electron donating compound contained in the active layer may be a low molecular compound or a high molecular compound. Examples of the low molecular weight compound include phthalocyanine, metal phthalocyanine, porphyrin, metal porphyrin, oligothiophene, tetracene, pentacene, and rubrene. Examples of the polymer compound include polyvinylcarbazole and derivatives thereof, polysilane and derivatives thereof, polysiloxane derivatives having an aromatic amine residue in the side chain or main chain, polyaniline and derivatives thereof, polythiophene and derivatives thereof, polypyrrole and derivatives thereof, polyphenylene Examples include vinylene and its derivatives, polythienylene vinylene and its derivatives, polyfluorene and its derivatives, and the like.

The electron-accepting compound contained in the active layer may be a low molecular compound or a high molecular compound. Low molecular weight compounds include oxadiazole derivatives, anthraquinodimethane and its derivatives, benzoquinone and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, tetracyanoanthraquinodimethane and its derivatives, fluorenone derivatives, diphenyldicyanoethylene and its derivatives, diphenoquinone derivatives, 8-hydroxyquinoline and metal complexes of derivatives thereof, polyquinoline and derivatives thereof, polyquinoxaline and its derivatives, polyfluorene and its derivatives, fullerene and derivatives thereof such as C _60, 2,9-dimethyl - Examples thereof include phenanthroline derivatives such as 4,7-diphenyl-1,10-phenanthroline (basocuproin). Examples of the polymer compound include polyvinylcarbazole and derivatives thereof, polysilane and derivatives thereof, polysiloxane derivatives having an aromatic amine residue in the side chain or main chain, polyaniline and derivatives thereof, polythiophene and derivatives thereof, polypyrrole and derivatives thereof, polyphenylene Examples include vinylene and its derivatives, polythienylene vinylene and its derivatives, polyfluorene and its derivatives, and the like. Among these, fullerene and its derivatives are preferable.

Fullerenes and derivatives thereof include C ₆₀ , C ₇₀ , C ₈₄ and derivatives thereof. A fullerene derivative represents a compound in which at least a part of fullerene is modified.

（Ｉ） （ＩＩ） （ＩＩＩ） （ＩＶ）

（式（Ｉ）〜（ＩＶ）中、Ｒ^ａは、アルキル基、アリール基、ヘテロアリール基又はエステル構造を有する基である。複数個あるＲ^ａは、同一であっても相異なってもよい。Ｒ^ｂはアルキル基又はアリール基を表す。複数個あるＲ^ｂは、同一であっても相異なってもよい。） Examples of the fullerene derivative include a compound represented by the formula (I), a compound represented by the formula (II), a compound represented by the formula (III), and a compound represented by the formula (IV).

(I) (II) (III) (IV)

(In formulas (I) to (IV), R ^a is an alkyl group, aryl group, heteroaryl group or group having an ester structure. A plurality of R ^a may be the same or different. R ^b represents an alkyl group or an aryl group, and a plurality of R ^b may be the same or different.)

Examples of the alkyl group represented by R ^a and R ^b include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a hexyl group, and an octyl group. It is done. Examples of the aryl group represented by R ^a and R ^b include a phenyl group, a naphthyl group, an anthryl group, and a fluorenyl group. Examples of the heteroaryl group represented by R ^a and R ^b include a chenyl group, a pyrrolyl group, a furyl group, a pyridyl group, a piperidyl group, a quinolyl group, and an isoquinolyl group.

（Ｖ）
〔式中、ｕ１は、１〜６の整数を表し、ｕ２は、０〜６の整数を表し、ｕ３は０又は１の整数を表し、ｕ４は、０又は１の整数を表す。ただし、ｕ３とｕ４の和は１である。Ｒ^ｃは、アルキル基、アリール基又はヘテロアリール基を表す。〕 Examples of the group having an ester structure represented by ^Ra include a group represented by the formula (V).

(V)
[Wherein u1 represents an integer of 1 to 6, u2 represents an integer of 0 to 6, u3 represents an integer of 0 or 1, and u4 represents an integer of 0 or 1. However, the sum of u3 and u4 is 1. R ^c represents an alkyl group, an aryl group, or a heteroaryl group. ]

The definitions and specific examples of the alkyl group, aryl group and heteroaryl group represented by R ^c are the same as the definitions and specific examples of the alkyl group, aryl group and heteroaryl group represented by R ^a .

Specific examples of the C ₆₀ derivative include the following.

Specific examples of the C ₇₀ derivative include the following.

  The thickness of the active layer is usually 1 nm to 100 μm, preferably 2 nm to 1000 nm, more preferably 5 nm to 500 nm, and further preferably 20 nm to 200 nm.

  Examples of the method for forming the active layer include a method of forming a film from a composition containing a solvent, a conjugated polymer compound, and a fullerene derivative. Examples of the solvent include unsaturated hydrocarbon solvents such as toluene, xylene, mesitylene, tetralin, decalin, bicyclohexyl, butylbenzene, sec-butylbesen, and tert-butylbenzene, carbon tetrachloride, chloroform, dichloromethane, dichloroethane, chlorobutane, Halogenated saturated hydrocarbon solvents such as bromobutane, chloropentane, bromopentane, chlorohexane, bromohexane, chlorocyclohexane, bromocyclohexane, halogenated unsaturated hydrocarbon solvents such as chlorobenzene, dichlorobenzene, trichlorobenzene, tetrahydrofuran, tetrahydropyran, etc. And ether solvents. For the film formation, a method similar to the method described in the method for forming the hole transport layer can be used.

  Examples of the conjugated polymer compound include an unsubstituted or substituted fluorenediyl group, an unsubstituted or substituted benzofluorenediyl group, an unsubstituted or substituted dibenzofurandiyl group, an unsubstituted or substituted dibenzothiophenediyl group, Unsubstituted or substituted carbazolediyl group, unsubstituted or substituted thiophenediyl group, unsubstituted or substituted furandyl group, unsubstituted or substituted pyrroldiyl group, unsubstituted or substituted benzothiadiazolediyl group, unsubstituted or substituted Examples of the polymer compound include a vinylene group and one or more groups selected from the group consisting of an unsubstituted or substituted triphenylaminediyl group as a repeating unit, and the repeating units are bonded directly or via a linking group. .

  In the conjugated polymer compound, when the repeating units are bonded to each other via a linking group, examples of the linking group include a phenylene group, a biphenylylene group, a naphthalenediyl group, and an anthracenediyl group.

  Preferable examples of the conjugated polymer compound include a polymer in which one or more groups selected from the group consisting of a fluorenediyl group and a thiophenediyl group are included as a repeating unit, and the repeating units are bonded directly or via a linking group. Compounds.

(electrode)
The organic photoelectric conversion element of the present invention has a pair of electrodes. One electrode of the pair of electrodes is an anode, and the other electrode is a cathode. At least one of the pair of electrodes is preferably transparent or translucent. Examples of the material for the transparent or translucent electrode include a conductive metal oxide film and a translucent metal thin film. Specifically, indium oxide, zinc oxide, tin oxide, indium tin oxide (abbreviated as ITO), indium zinc oxide (abbreviated as IZO), gold, platinum, silver, and copper can be given. ITO, IZO and tin oxide are preferred. Moreover, you may use organic transparent conductive films, such as polyaniline and its derivative (s), polythiophene, and its derivative (s) as an electrode.

  One electrode of the pair of electrodes included in the organic photoelectric conversion element of the present invention may be opaque. As the opaque electrode, for example, a metal thin film having a thickness that does not transmit light can be used. Examples of opaque electrode materials include lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium, ytterbium, Examples include metals such as gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten, and tin, and alloys of two or more thereof, graphite, or graphite intercalation compounds.

  Examples of the method for producing the electrode include a vacuum deposition method, a sputtering method, an ion plating method, a plating method, and the like. In addition, a metal electrode can be produced by a coating method using a metal ink, a metal paste, a low melting point metal, or the like.

  In the element (a) and the element (b) described above, an additional layer is further provided between the anode and the active layer, between the active layer and the cathode, or between the active layer and the joined body. Also good. Examples of the additional layer include charge transport layers such as an electron transport layer and a hole transport layer. Examples of the material included in the additional layer include the above-described electron donating compounds, electron accepting compounds, alkali metal or alkaline earth metal halides such as lithium fluoride, alkali metal or alkaline earth metal oxides, Fine particles of inorganic semiconductor such as titanium oxide can be mentioned.

  The organic photoelectric conversion element of this embodiment can be operated as an organic thin-film solar cell by generating photovoltaic power between electrodes by irradiating light such as sunlight from a transparent or translucent electrode. By integrating a plurality of organic thin film solar cells, it can also be used as an organic thin film solar cell module. In addition, by applying light from a transparent or translucent electrode while a voltage is applied between the electrodes, a photocurrent flows and it can be operated as an organic photosensor. It can also be used as an organic image sensor by integrating a plurality of organic photosensors.

  Examples will be shown below for illustrating the present invention in more detail, but the present invention is not limited to these examples.

The polystyrene equivalent weight average molecular weight of the polymer compound was determined by size exclusion chromatography (SEC).
Column: TOSOH TSKgel SuperHM-H (2) + TSKgel SuperH2000 (4.6 mm Id x 15 cm); Detector: RI (SHIMADZU RID-10A); Mobile phase: Tetrahydrofuran (THF)

フラスコ内の気体をアルゴンで置換した１０００ｍＬの４つ口フラスコに、３−ブロモチオフェンを１３．０ｇ（８０．０ｍｍｏｌ）、ジエチルエーテルを８０ｍＬ入れて均一な溶液とした。該溶液を−７８℃に保ったまま、２．６Ｍのブチルリチウム（ｎ−ＢｕＬｉ）のヘキサン溶液を３１ｍＬ（８０．６ｍｍｏｌ）滴下した。−７８℃で２時間反応させた後、８．９６ｇの３−チオフェンアルデヒド（８０．０ｍｍｏｌ)を２０ｍＬのジエチルエーテルに溶解させた溶液を反応液に滴下した。滴下後、反応液を−７８℃で３０分攪拌し、さらに室温（２５℃）で３０分攪拌した。反応液を再度−７８℃に冷却し、２．６Ｍのｎ−ＢｕＬｉのヘキサン溶液６２ｍＬ（１６１ｍｍｏｌ）を１５分かけて滴下した。滴下後、反応液を−２５℃で２時間攪拌し、さらに室温（２５℃）で１時間攪拌した。その後、反応液を−２５℃に冷却し、６０ｇのヨウ素(２３６ｍｍｏｌ)を１０００ｍＬのジエチルエーテルに溶解させた溶液を３０分かけて滴下した。滴下後、反応液を室温（２５℃）で２時間攪拌し、１規定のチオ硫酸ナトリウム水溶液５０ｍＬを加えて反応を停止させた。反応液にジエチルエーテルを加え、反応生成物を含む有機層を抽出した後、硫酸マグネシウムで反応生成物を含む有機層を乾燥し、有機層を濾過後、濾液を濃縮して３５gの粗生成物を得た。クロロホルムを用いて粗生成物を再結晶することにより精製し、化合物１を２８ｇ得た。 Reference example 1
(Synthesis of Compound 1)

A 1000 mL four-necked flask in which the gas in the flask was replaced with argon was charged with 13.0 g (80.0 mmol) of 3-bromothiophene and 80 mL of diethyl ether to obtain a uniform solution. While maintaining the solution at −78 ° C., 31 mL (80.6 mmol) of 2.6M butyllithium (n-BuLi) in hexane was added dropwise. After reacting at −78 ° C. for 2 hours, a solution prepared by dissolving 8.96 g of 3-thiophenaldehyde (80.0 mmol) in 20 mL of diethyl ether was added dropwise to the reaction solution. After dropping, the reaction solution was stirred at -78 ° C for 30 minutes, and further stirred at room temperature (25 ° C) for 30 minutes. The reaction solution was cooled again to −78 ° C., and 62 mL (161 mmol) of 2.6 M n-BuLi in hexane was added dropwise over 15 minutes. After dropping, the reaction solution was stirred at −25 ° C. for 2 hours, and further stirred at room temperature (25 ° C.) for 1 hour. Thereafter, the reaction solution was cooled to −25 ° C., and a solution obtained by dissolving 60 g of iodine (236 mmol) in 1000 mL of diethyl ether was added dropwise over 30 minutes. After the dropwise addition, the reaction solution was stirred at room temperature (25 ° C.) for 2 hours, and 50 mL of 1N aqueous sodium thiosulfate solution was added to stop the reaction. Diethyl ether was added to the reaction solution, and the organic layer containing the reaction product was extracted, then the organic layer containing the reaction product was dried over magnesium sulfate, the organic layer was filtered, and the filtrate was concentrated to give 35 g of crude product. Got. The crude product was purified by recrystallization using chloroform to obtain 28 g of Compound 1.

３００ｍＬの４つ口フラスコに、ビスヨードチエニルメタノール（化合物１）を１０ｇ(２２．３ｍｍｏｌ)、塩化メチレンを１５０ｍＬ加えて均一な溶液とした。該溶液にクロロクロム酸ピリジニウムを７．５０ｇ(３４．８ｍｍｏｌ)加え、室温（２５℃）で１０時間攪拌した。反応液を濾過して不溶物を除去後、濾液を濃縮し、化合物２を１０．０ｇ（２２．４ｍｍｏｌ）得た。 Reference example 2
(Synthesis of Compound 2)

To a 300 mL four-necked flask, 10 g (22.3 mmol) of bisiodothienylmethanol (Compound 1) and 150 mL of methylene chloride were added to obtain a uniform solution. To the solution, 7.50 g (34.8 mmol) of pyridinium chlorochromate was added and stirred at room temperature (25 ° C.) for 10 hours. The reaction solution was filtered to remove insoluble matters, and then the filtrate was concentrated to obtain 10.0 g (22.4 mmol) of Compound 2.

フラスコ内の気体をアルゴンで置換した３００ｍＬフラスコに、化合物２を１０．０ｇ(２２．３ｍｍｏｌ)、銅粉末を６．０ｇ（９４．５ｍｍｏｌ）、脱水Ｎ，Ｎ−ジメチルホルムアミド（以下、ＤＭＦと呼称することもある）を１２０ｍＬ加えて、１２０℃で４時間攪拌した。反応後、フラスコを室温（２５℃）まで冷却し、反応液をシリカゲルカラムに通して不溶成分を除去した。その後、反応液に水５００ｍＬを加え、さらにクロロホルムを加え、反応生成物を含む有機層を抽出した。クロロホルム溶液である有機層を硫酸マグネシウムで乾燥し、有機層を濾過し、濾液を濃縮して粗生成物を得た。粗生成物を、展開液がクロロホルムであるシリカゲルカラムで精製し、化合物３を３．２６ｇ得た。 Reference example 3
(Synthesis of Compound 3)

In a 300 mL flask in which the gas in the flask was replaced with argon, 10.0 g (22.3 mmol) of Compound 2 and 6.0 g (94.5 mmol) of copper powder, dehydrated N, N-dimethylformamide (hereinafter referred to as DMF). 120 mL) was added and stirred at 120 ° C. for 4 hours. After the reaction, the flask was cooled to room temperature (25 ° C.), and the reaction solution was passed through a silica gel column to remove insoluble components. Thereafter, 500 mL of water was added to the reaction solution, and chloroform was further added to extract an organic layer containing the reaction product. The organic layer as a chloroform solution was dried over magnesium sulfate, the organic layer was filtered, and the filtrate was concentrated to obtain a crude product. The crude product was purified with a silica gel column whose developing solution was chloroform, and 3.26 g of compound 3 was obtained.

メカニカルスターラーを備え、フラスコ内の気体をアルゴンで置換した３００ｍＬ４つ口フラスコに、化合物３を３．８５ｇ（２０．０ｍｍｏｌ）、クロロホルムを５０ｍＬ、トリフルオロ酢酸を５０ｍＬ入れて均一な溶液とした。該溶液に過ホウ酸ナトリウム１水和物を５．９９ｇ(６０ｍｍｏｌ)加え、室温（２５℃）で４５分間攪拌した。その後、反応液に水２００ｍＬを加え、さらにクロロホルムを加え、反応生成物を含む有機層を抽出した。クロロホルム溶液である有機層をシリカゲルカラムに通し、エバポレーターで濾液の溶媒を留去した。メタノールを用いて残渣を再結晶し、化合物４を５３４ｍｇ得た。 Reference example 4
(Synthesis of Compound 4)

A uniform solution was prepared by adding 3.85 g (20.0 mmol) of Compound 3, 50 mL of chloroform, and 50 mL of trifluoroacetic acid to a 300 mL four-necked flask equipped with a mechanical stirrer and replacing the gas in the flask with argon. To the solution, 5.99 g (60 mmol) of sodium perborate monohydrate was added and stirred at room temperature (25 ° C.) for 45 minutes. Thereafter, 200 mL of water was added to the reaction solution, chloroform was further added, and the organic layer containing the reaction product was extracted. The organic layer, which is a chloroform solution, was passed through a silica gel column, and the solvent of the filtrate was distilled off with an evaporator. The residue was recrystallized using methanol to obtain 534 mg of compound 4.

¹ H NMR in CDCl ₃ (ppm): 7.64 (d, 1H), 7.43 (d, 1H), 7.27 (d, 1H), 7.10 (d, 1H)

フラスコ内の気体をアルゴンで置換した１００ｍＬ四つ口フラスコに、化合物４を１．００ｇ（４．８０ｍｍｏｌ）と脱水ＴＨＦを３０ｍｌ入れて均一な溶液とした。フラスコを−２０℃に保ちながら、反応液に１Ｍの３，７−ジメチルオクチルマグネシウムブロミドのジエチルエーテル溶液を１２．７ｍＬ加えた。その後、３０分かけて温度を−５℃まで上げ、そのままの温度で反応液を３０分攪拌した。その後、１０分かけて温度を０℃に上げ、そのままの温度で反応液を１．５時間攪拌した。その後、反応液に水を加えて反応を停止し、さらに酢酸エチルを加え、反応生成物を含む有機層を抽出した。酢酸エチル溶液である有機層を硫酸ナトリウムで乾燥し、有機層を濾過後、酢酸エチル溶液をシリカゲルカラムに通し、濾液の溶媒を留去し、化合物５を１．５０ｇ得た。 Reference Example 5
(Synthesis of Compound 5)

A 100 mL four-necked flask in which the gas in the flask was replaced with argon was charged with 1.00 g (4.80 mmol) of Compound 4 and 30 ml of dehydrated THF to obtain a uniform solution. While maintaining the flask at −20 ° C., 12.7 mL of a 1M 3,7-dimethyloctylmagnesium bromide diethyl ether solution was added to the reaction solution. Thereafter, the temperature was raised to −5 ° C. over 30 minutes, and the reaction solution was stirred at the same temperature for 30 minutes. Thereafter, the temperature was raised to 0 ° C. over 10 minutes, and the reaction solution was stirred at the same temperature for 1.5 hours. Thereafter, water was added to the reaction solution to stop the reaction, and ethyl acetate was further added to extract an organic layer containing the reaction product. The organic layer, which is an ethyl acetate solution, was dried over sodium sulfate, the organic layer was filtered, the ethyl acetate solution was passed through a silica gel column, and the solvent of the filtrate was distilled off to obtain 1.50 g of compound 5.

¹ H NMR in CDCl ₃ (ppm): 8.42 (b, 1H), 7.25 (d, 1H), 7.20 (d, 1H), 6.99 (d, 1H), 6.76 ( d, 1H), 2.73 (b, 1H), 1.90 (m, 4H), 1.58-1.02 (b, 20H), 0.92 (s, 6H), 0.88 (s) , 12H)

フラスコ内の気体をアルゴンで置換した２００ｍＬフラスコに、化合物５を１．５０ｇ、トルエンを３０ｍＬ入れて均一な溶液とした。該溶液にｐ−トルエンスルホン酸ナトリウム１水和物を１００ｍｇ入れ、１００℃で１．５時間攪拌を行った。反応液を室温（２５℃）まで冷却後、水５０ｍＬを加え、さらにトルエンを加えて反応生成物を含む有機層を抽出した。トルエン溶液である有機層を硫酸ナトリウムで乾燥し、有機層を濾過後、溶媒を留去した。得られた粗生成物を、展開溶媒がヘキサンであるシリカゲルカラムで生成し、化合物６を１．３３ｇ得た。ここまでの操作を複数回行った。 Reference Example 6
(Synthesis of Compound 6)

In a 200 mL flask in which the gas in the flask was replaced with argon, 1.50 g of Compound 5 and 30 mL of toluene were added to obtain a uniform solution. 100 mg of sodium p-toluenesulfonate monohydrate was added to the solution, and the mixture was stirred at 100 ° C. for 1.5 hours. After cooling the reaction solution to room temperature (25 ° C.), 50 mL of water was added, and toluene was further added to extract the organic layer containing the reaction product. The organic layer which is a toluene solution was dried with sodium sulfate, the organic layer was filtered, and then the solvent was distilled off. The obtained crude product was produced on a silica gel column whose developing solvent was hexane, and 1.33 g of compound 6 was obtained. The operation so far was performed several times.

¹ H NMR in CDCl ₃ (ppm): 6.98 (d, 1H), 6.93 (d, 1H), 6.68 (d, 1H), 6.59 (d, 1H), 1.89 ( m, 4H), 1.58-1.00 (b, 20H), 0.87 (s, 6H), 0.86 (s, 12H)

フラスコ内の気体をアルゴンで置換した２００ｍＬフラスコに、化合物６を２．１６ｇ(４．５５ｍｍｏｌ)、脱水ＴＨＦを１００ｍＬ入れて均一な溶液とした。該溶液を−７８℃に保ち、該溶液に２．６Ｍのブチルリチウム（ｎ−ＢｕＬｉ）のヘキサン溶液４．３７ｍＬ（１１．４ｍｍｏｌ）を１０分かけて滴下した。滴下後、反応液を−７８℃で３０分攪拌し、次いで、室温（２５℃）で２時間攪拌した。その後、フラスコを−７８℃に冷却し、反応液にトリブチルスズクロリドを４．０７ｇ（１２．５ｍｍｏｌ）加えた。添加後、反応液を−７８℃で３０分攪拌し、次いで、室温（２５℃）で３時間攪拌した。その後、反応液に水２００ｍｌを加えて反応を停止し、酢酸エチルを加えて反応生成物を含む有機層を抽出した。酢酸エチル溶液である有機層を硫酸ナトリウムで乾燥し、有機層を濾過後、濾液をエバポレーターで濃縮し、溶媒を留去した。得られたオイル状の物質を展開溶媒がヘキサンであるシリカゲルカラムで精製した。シリカゲルカラムのシリカゲルには、あらかじめ５重量（ｗｔ）％のトリエチルアミンを含むヘキサンに５分間浸し、その後、ヘキサンで濯いだシリカゲルを用いた。精製後、化合物７を３．５２ｇ（３．３４ｍｍｏｌ）得た。 Reference Example 7
(Synthesis of Compound 7)

Into a 200 mL flask in which the gas in the flask was replaced with argon, 2.16 g (4.55 mmol) of Compound 6 and 100 mL of dehydrated THF were added to obtain a uniform solution. The solution was kept at −78 ° C., and 4.37 mL (11.4 mmol) of 2.6M butyllithium (n-BuLi) in hexane was added dropwise to the solution over 10 minutes. After the addition, the reaction solution was stirred at -78 ° C for 30 minutes, and then stirred at room temperature (25 ° C) for 2 hours. Thereafter, the flask was cooled to −78 ° C., and 4.07 g (12.5 mmol) of tributyltin chloride was added to the reaction solution. After the addition, the reaction solution was stirred at −78 ° C. for 30 minutes, and then stirred at room temperature (25 ° C.) for 3 hours. Thereafter, 200 ml of water was added to the reaction solution to stop the reaction, and ethyl acetate was added to extract an organic layer containing the reaction product. The organic layer as an ethyl acetate solution was dried over sodium sulfate, the organic layer was filtered, the filtrate was concentrated with an evaporator, and the solvent was distilled off. The obtained oily substance was purified by a silica gel column whose developing solvent was hexane. As the silica gel of the silica gel column, silica gel previously immersed in hexane containing 5% by weight of triethylamine for 5 minutes and then rinsed with hexane was used. After purification, 3.52 g (3.34 mmol) of compound 7 was obtained.

フラスコ内の気体をアルゴンで置換した２００ｍＬフラスコに、化合物７を２００ｍｇ（０．１９０ｍｍｏｌ）、化合物８（Ｌｕｍｉｎｅｓｃｅｎｃｅ Ｔｅｃｈｎｏｌｏｇｙ Ｃｏｒｐｏｒａｔｉｏｎ社製）を１１５ｍｇ（０．１８４ｍｍｏｌ）、トルエンを１６ｍｌ入れて均一溶液とした。得られたトルエン溶液を、アルゴンで３０分バブリングした。その後、トルエン溶液に、トリス（ジベンジリデンアセトン）ジパラジウムを２．６１ｍｇ（０．００２８５ｍｍｏｌ）、トリス(２−トルイル)ホスフィンを５．２ｍｇ（０．０１７１ｍｍｏｌ）加え、１００℃で５時間攪拌した。その後、反応液にフェニルブロミドを１００ｍｇ加え、さらに５時間攪拌した。その後、フラスコを２５℃に冷却し、反応液をメタノール３００ｍＬに注いだ。析出したポリマーを濾過して回収し、得られたポリマーを円筒濾紙に入れ、ソックスレー抽出器を用いて、メタノール、アセトン及びヘキサンでそれぞれ５時間抽出した。円筒濾紙内に残ったポリマーを、トルエン１００ｍＬに溶解させ、ジエチルジチオカルバミン酸ナトリウム３ｇと水１００ｍＬを加え、８時間還流下で攪拌を行った。水層を除去後、有機層を水５０ｍｌで２回洗浄し、次いで、３重量％（ｗｔ%）の酢酸水溶液５０ｍＬで２回洗浄し、次いで、水５０ｍＬで２回洗浄し、次いで、５重量％のフッ化カリウム水溶液５０ｍLで２回洗浄し、次いで、水５０ｍLで２回洗浄し、得られた溶液をメタノールに注いでポリマーを析出させた。ポリマーを濾過後、乾燥し、得られたポリマーをｏ−ジクロロベンゼン５０ｍＬに再度溶解し、アルミナ／シリカゲルカラムを通した。得られた溶液をメタノールに注いでポリマーを析出させ、ポリマーを濾過後、乾燥し、精製された高分子化合物を８３ｍｇ得た。以下、該高分子化合物を高分子化合物１と呼称する。 Reference Example 8
(Synthesis of polymer compound 1)

A 200 mL flask in which the gas in the flask was replaced with argon was charged with 200 mg (0.190 mmol) of Compound 7, 115 mg (0.184 mmol) of Compound 8 (manufactured by Luminescence Technology Corporation), and 16 ml of toluene to obtain a uniform solution. The resulting toluene solution was bubbled with argon for 30 minutes. Thereafter, 2.61 mg (0.00285 mmol) of tris (dibenzylideneacetone) dipalladium and 5.2 mg (0.0171 mmol) of tris (2-toluyl) phosphine were added to the toluene solution, and the mixture was stirred at 100 ° C. for 5 hours. Thereafter, 100 mg of phenyl bromide was added to the reaction solution, and the mixture was further stirred for 5 hours. Thereafter, the flask was cooled to 25 ° C., and the reaction solution was poured into 300 mL of methanol. The precipitated polymer was collected by filtration, and the obtained polymer was placed in a cylindrical filter paper and extracted with methanol, acetone and hexane for 5 hours using a Soxhlet extractor. The polymer remaining in the cylindrical filter paper was dissolved in 100 mL of toluene, 3 g of sodium diethyldithiocarbamate and 100 mL of water were added, and the mixture was stirred under reflux for 8 hours. After removal of the aqueous layer, the organic layer is washed twice with 50 ml of water, then twice with 50 mL of 3 wt% (wt%) aqueous acetic acid, then twice with 50 mL of water and then 5 wt. The solution was washed twice with 50 mL of an aqueous potassium fluoride solution and then twice with 50 mL of water, and the resulting solution was poured into methanol to precipitate a polymer. The polymer was filtered and dried, and the obtained polymer was redissolved in 50 mL of o-dichlorobenzene and passed through an alumina / silica gel column. The obtained solution was poured into methanol to precipitate a polymer, and the polymer was filtered and dried to obtain 83 mg of a purified polymer compound. Hereinafter, the polymer compound is referred to as polymer compound 1.

フラスコ内の気体をアルゴンで置換した２Ｌ四つ口フラスコに、化合物（Ｅ）を７．９２８ｇ（１６．７２ｍｍｏｌ）、化合物（Ｆ）を１３．００ｇ（１７．６０ｍｍｏｌ）、トリオクチルメチルアンモニウムクロリド（商品名Ａｌｉｑｕａｔ３３６（登録商標）、アルドリッチ社製、CH₃N[(CH₂)₇CH₃]₃Cl、density 0.884g/ml、25℃）を４．９７９ｇ、及びトルエンを４０５ｍｌ入れ、撹拌しながら反応系内を３０分間アルゴンバブリングした。フラスコ内にジクロロビス（トリフェニルホスフィン）パラジウム（ＩＩ）を０．０２ｇ加え、１０５℃に昇温し、撹拌しながら２ｍｏｌ／Ｌの炭酸ナトリウム水溶液４２．２ｍｌを滴下した。滴下終了後５時間反応させ、その後、フェニルボロン酸２．６ｇとトルエン１．８ｍｌとを加え、１０５℃で１６時間撹拌した。その後、反応液にトルエン７００ｍｌ及び７．５ｗｔ％のジエチルジチオカルバミン酸ナトリウム三水和物水溶液２００ｍｌを加え、８５℃で３時間撹拌した。反応液の水層を除去後、有機層を６０℃のイオン交換水３００ｍｌで２回、６０℃の３ｗｔ％酢酸３００ｍｌで１回、さらに６０℃のイオン交換水３００ｍｌで３回洗浄した。有機層をセライト、アルミナ及びシリカを充填したカラムに通し、濾液を回収した。その後、熱トルエン８００ｍｌでカラムを洗浄し、洗浄後のトルエン溶液を濾液に加えた。得られた溶液を７００ｍｌまで濃縮した後、濃縮した溶液を２Ｌのメタノールに加え、高分子化合物を再沈殿させた。高分子化合物を濾過して回収し、５００ｍｌのメタノール、５００ｍｌのアセトン、５００ｍｌのメタノールで高分子化合物を洗浄した。高分子化合物を５０℃で一晩真空乾燥することにより、ペンタチエニル−フルオレンコポリマー（高分子化合物２）１２．２１ｇを得た。高分子化合物２のポリスチレン換算の重量平均分子量は１．１×１０⁵であった。 Reference Example 9
(Synthesis of polymer compound 2)

Into a 2 L four-necked flask in which the gas in the flask was replaced with argon, 7.928 g (16.72 mmol) of compound (E), 13.00 g (17.60 mmol) of compound (F), trioctylmethylammonium chloride ( 4.979 g of trade name Aliquat 336 (registered trademark), manufactured by Aldrich, CH ₃ N [(CH ₂ ) ₇ CH ₃ ] ₃ Cl, density 0.884 g / ml, 25 ° C.) and 405 ml of toluene are added and stirred. The reaction system was bubbled with argon for 30 minutes. 0.02 g of dichlorobis (triphenylphosphine) palladium (II) was added to the flask, the temperature was raised to 105 ° C., and 42.2 ml of a 2 mol / L sodium carbonate aqueous solution was added dropwise with stirring. After completion of the dropwise addition, the reaction was allowed to proceed for 5 hours, and then 2.6 g of phenylboronic acid and 1.8 ml of toluene were added, followed by stirring at 105 ° C. for 16 hours. Thereafter, 700 ml of toluene and 200 ml of a 7.5 wt% sodium diethyldithiocarbamate trihydrate aqueous solution were added to the reaction solution, followed by stirring at 85 ° C. for 3 hours. After removing the aqueous layer of the reaction solution, the organic layer was washed twice with 300 ml of ion exchange water at 60 ° C., once with 300 ml of 3 wt% acetic acid at 60 ° C., and further three times with 300 ml of ion exchange water at 60 ° C. The organic layer was passed through a column packed with celite, alumina and silica, and the filtrate was collected. Thereafter, the column was washed with 800 ml of hot toluene, and the washed toluene solution was added to the filtrate. After the obtained solution was concentrated to 700 ml, the concentrated solution was added to 2 L of methanol to reprecipitate the polymer compound. The polymer compound was recovered by filtration, and the polymer compound was washed with 500 ml of methanol, 500 ml of acetone, and 500 ml of methanol. The polymer compound was vacuum-dried at 50 ° C. overnight to obtain 12.21 g of a pentathienyl-fluorene copolymer (polymer compound 2). The weight average molecular weight in terms of polystyrene of the polymer compound 2 was 1.1 × 10 ⁵ .

２００ｍｌのセパラブルフラスコに、メチルトリオクチルアンモニウムクロライド（商品名：aliquat336（登録商標）、Aldrich製、CH₃N[(CH₂)₇CH₃]₃Cl、density ０．８８４ｇ／ｍｌ、２５℃）を０．６５ｇ、化合物（Ｇ）を１．５７７９ｇ、化合物（Ｉ）を１．１４５４ｇ入れ、フラスコ内の気体を窒素で置換した。フラスコに、アルゴンバブリングしたトルエンを３５ｍｌ加え、撹拌溶解後、さらに４０分アルゴンバブリングした。フラスコを加熱するバスの温度を８５℃まで昇温後、反応液に、酢酸パラジウム１．６ｍｇ、トリスｏ−メトキシフェニルフォスフィンを６．７ｍｇ加え、つづいてバスの温度を１０５℃まで昇温しながら、１７．５重量％の炭酸ナトリウム水溶液９．５ｍｌを６分かけて滴下した。滴下後、バスの温度を１０５℃に保った状態で１．７時間攪拌し、その後、反応液を室温まで冷却した。 Reference Example 10
(Synthesis of polymer compound 3)

In a 200 ml separable flask, methyl trioctyl ammonium chloride (trade name: aliquat336 (registered trademark), manufactured by Aldrich, CH ₃ N [(CH ₂ ) ₇ CH ₃ ] ₃ Cl, density 0.884 g / ml, 25 ° C.) 0.65 g, compound (G) 1.5779 g and compound (I) 1.1454 g, and the gas in the flask was replaced with nitrogen. 35 ml of toluene bubbled with argon was added to the flask, stirred and dissolved, and then bubbled with argon for 40 minutes. After raising the temperature of the bath for heating the flask to 85 ° C., 1.6 mg of palladium acetate and 6.7 mg of tris o-methoxyphenylphosphine were added to the reaction solution, and then the temperature of the bath was raised to 105 ° C. However, 9.5 ml of a 17.5% by weight aqueous sodium carbonate solution was added dropwise over 6 minutes. After dropping, the mixture was stirred for 1.7 hours while maintaining the bath temperature at 105 ° C., and then the reaction solution was cooled to room temperature.

  Next, 1.0877 g of compound (G) and 0.9399 g of compound (H) were added to the reaction solution, and 15 ml of toluene bubbled with argon was further added. After stirring and dissolving, argon was bubbled for another 30 minutes. To the reaction solution, 1.3 mg of palladium acetate and 4.7 mg of tris o-methoxyphenylphosphine were added, and then the temperature of the bath was raised to 105 ° C., and 6.8 ml of a 17.5 wt% sodium carbonate aqueous solution. Was added dropwise over 5 minutes. After the dropwise addition, the mixture was stirred for 3 hours while maintaining the bath temperature at 105 ° C. After stirring, 50 ml of argon bubbled toluene, 2.3 mg of palladium acetate, 8.8 mg of tris o-methoxyphenylphosphine, and 0.305 g of phenylboric acid were added to the reaction solution, and the bath temperature was maintained at 105 ° C. The mixture was stirred for 8 hours. Next, after removing the aqueous layer of the reaction solution, an aqueous solution in which 3.1 g of sodium N, N-diethyldithiocarbamate was dissolved in 30 ml of water was added, and the mixture was stirred for 2 hours while maintaining the bath temperature at 85 ° C. . Subsequently, 250 ml of toluene was added to the reaction solution to separate the reaction solution, and the organic layer was washed twice with 65 ml of water, twice with 65 ml of 3% by weight acetic acid and twice with 65 ml of water. The washed organic layer was diluted by adding 150 ml of toluene, and dropped into 2500 ml of methanol to reprecipitate the polymer compound. The polymer compound was filtered, dried under reduced pressure, and dissolved in 500 ml of toluene. The obtained toluene solution was passed through a silica gel-alumina column, and the obtained toluene solution was added dropwise to 3000 ml of methanol to reprecipitate the polymer compound. The polymer compound was filtered and dried under reduced pressure to obtain 3.00 g of polymer compound 3. The obtained polymer compound 3 had a polystyrene equivalent weight average molecular weight of 257,000 and a number average molecular weight of 87,000.

Polymer compound 3 is
It is a block copolymer represented by the following formula.

５００ｍｌフラスコに、４，５−ジフルオロ−１，２−ジアミノベンゼン（東京化成工業製）を１０．２ｇ（７０．８ｍｍｏｌ）、ピリジンを１５０ｍＬ入れて均一溶液とした。フラスコを０℃に保ったまま、フラスコ内に塩化チオニル１６．０ｇ（１３４ｍｍｏｌ）を滴下した。滴下後、フラスコを２５℃に温めて、６時間反応を行った。その後、水２５０ｍｌを加え、クロロホルムで反応生成物を抽出した。クロロホルム溶液である有機層を硫酸ナトリウムで乾燥し、濾過した。濾液をエバポレーターで濃縮して析出した固体を再結晶で精製した。再結晶の溶媒には、メタノールを用いた。精製後、化合物９を１０．５ｇ（６１．０ｍｍｏｌ）得た。 Reference Example 11
(Synthesis of Compound 9)

In a 500 ml flask, 10.5 g (70.8 mmol) of 4,5-difluoro-1,2-diaminobenzene (manufactured by Tokyo Chemical Industry Co., Ltd.) and 150 mL of pyridine were added to obtain a homogeneous solution. While maintaining the flask at 0 ° C., 16.0 g (134 mmol) of thionyl chloride was dropped into the flask. After dropping, the flask was warmed to 25 ° C. and reacted for 6 hours. Thereafter, 250 ml of water was added, and the reaction product was extracted with chloroform. The organic layer, which is a chloroform solution, was dried over sodium sulfate and filtered. The filtrate was concentrated with an evaporator and the precipitated solid was purified by recrystallization. Methanol was used as the solvent for recrystallization. After purification, 10.5 g (61.0 mmol) of Compound 9 was obtained.

１００ｍＬフラスコに、化合物９を２．００ｇ（１１．６ｍｍｏｌ）、鉄粉０．２０ｇ（３．５８ｍｍｏｌ）をいれ、フラスコを９０℃に加熱した。このフラスコに臭素３１ｇ（１９４ｍｍｏｌ）を１時間かけて滴下した。滴下後、９０℃で３８時間攪拌した。その後、フラスコを室温（２５℃）まで冷却し、クロロホルム１００ｍＬを入れて希釈した。得られた溶液を、５ｗｔ％の亜硫酸ナトリウム水溶液３００ｍＬに注ぎ込み、１時間攪拌した。得られた混合液の有機層を分液ロートで分離し、水層をクロロホルムで３回抽出した。得られた抽出液を先ほど分離した有機層と合わせて硫酸ナトリウムで乾燥した。濾過後、濾液をエバポレーターで濃縮し、溶媒を留去した。得られた黄色の固体を、５５℃に熱したメタノール９０ｍＬに溶解させ、その後、２５℃まで冷却した。析出した結晶を濾過回収し、その後、室温（２５℃）で減圧乾燥して化合物１０を１．５０ｇ得た。 Reference Example 12
(Synthesis of Compound 10)

In a 100 mL flask, 2.00 g (11.6 mmol) of Compound 9 and 0.20 g (3.58 mmol) of iron powder were added, and the flask was heated to 90 ° C. To this flask, 31 g (194 mmol) of bromine was added dropwise over 1 hour. After dropping, the mixture was stirred at 90 ° C. for 38 hours. Thereafter, the flask was cooled to room temperature (25 ° C.) and diluted with 100 mL of chloroform. The obtained solution was poured into 300 mL of 5 wt% aqueous sodium sulfite solution and stirred for 1 hour. The organic layer of the obtained mixture was separated with a separatory funnel, and the aqueous layer was extracted with chloroform three times. The obtained extract was combined with the organic layer separated earlier and dried over sodium sulfate. After filtration, the filtrate was concentrated with an evaporator and the solvent was distilled off. The obtained yellow solid was dissolved in 90 mL of methanol heated to 55 ° C., and then cooled to 25 ° C. The precipitated crystals were collected by filtration and then dried under reduced pressure at room temperature (25 ° C.) to obtain 1.50 g of compound 10.

¹⁹ F NMR (CDCl ₃ , ppm): -118.9 (s, 2F)

フラスコ内の気体をアルゴンで置換した２００ｍＬフラスコに、化合物７を５００ｍｇ（０．４７５ｍｍｏｌ）、化合物１０を１４１ｍｇ（０．４２７ｍｍｏｌ）、トルエンを３２ｍｌ入れて均一溶液とした。得られたトルエン溶液を、アルゴンで３０分バブリングした。その後、トルエン溶液に、トリス（ジベンジリデンアセトン）ジパラジウムを６．５２ｍｇ（０．００７ｍｍｏｌ）、トリス(２−トルイル)ホスフィンを１３．０ｍｇ加え、１００℃で６時間攪拌した。その後、反応液にフェニルブロミドを５００ｍｇ加え、さらに５時間攪拌した。その後、フラスコを２５℃に冷却し、反応液をメタノール３００ｍＬに注いだ。析出したポリマーを濾過して回収し、得られたポリマーを、円筒濾紙に入れ、ソックスレー抽出器を用いて、メタノール、アセトン及びヘキサンでそれぞれ５時間抽出した。円筒濾紙内に残ったポリマーを、トルエン１００ｍＬに溶解させ、ジエチルジチオカルバミン酸ナトリウム２ｇと水４０ｍＬを加え、８時間還流下で攪拌を行った。水層を除去後、有機層を水５０ｍｌで２回洗浄し、次いで、３ｗｔ%の酢酸水溶液５０ｍＬで２回洗浄し、次いで、水５０ｍＬで２回洗浄し、次いで、５％フッ化カリウム水溶液５０ｍLで２回洗浄し、次いで、水５０ｍLで２回洗浄し、得られた溶液をメタノールに注いでポリマーを析出させた。ポリマーを濾過後、乾燥し、得られたポリマーをｏ−ジクロロベンゼン５０ｍＬに再度溶解し、アルミナ／シリカゲルカラムを通した。得られた溶液をメタノールに注いでポリマーを析出させ、ポリマーを濾過後、乾燥し、精製された重合体１８５ｍｇを得た。以下、この重合体を高分子化合物４と呼称する。 Reference Example 13
(Synthesis of polymer compound 4)

A 200 mL flask in which the gas in the flask was replaced with argon was charged with 500 mg (0.475 mmol) of Compound 7, 141 mg (0.427 mmol) of Compound 10, and 32 ml of toluene to obtain a uniform solution. The resulting toluene solution was bubbled with argon for 30 minutes. Thereafter, 6.52 mg (0.007 mmol) of tris (dibenzylideneacetone) dipalladium and 13.0 mg of tris (2-toluyl) phosphine were added to the toluene solution, and the mixture was stirred at 100 ° C. for 6 hours. Thereafter, 500 mg of phenyl bromide was added to the reaction solution, and the mixture was further stirred for 5 hours. Thereafter, the flask was cooled to 25 ° C., and the reaction solution was poured into 300 mL of methanol. The precipitated polymer was collected by filtration, and the obtained polymer was put into a cylindrical filter paper and extracted with methanol, acetone and hexane for 5 hours each using a Soxhlet extractor. The polymer remaining in the cylindrical filter paper was dissolved in 100 mL of toluene, 2 g of sodium diethyldithiocarbamate and 40 mL of water were added, and the mixture was stirred under reflux for 8 hours. After removing the aqueous layer, the organic layer was washed twice with 50 ml of water, then twice with 50 mL of a 3 wt% aqueous acetic acid solution, then twice with 50 mL of water, and then 50 mL of 5% aqueous potassium fluoride solution. And then washed twice with 50 mL of water, and the resulting solution was poured into methanol to precipitate a polymer. The polymer was filtered and dried, and the obtained polymer was redissolved in 50 mL of o-dichlorobenzene and passed through an alumina / silica gel column. The obtained solution was poured into methanol to precipitate a polymer, and the polymer was filtered and dried to obtain 185 mg of a purified polymer. Hereinafter, this polymer is referred to as polymer compound 4.

(Manufacture of coating solution 1)
25 parts by weight of [6,6] -phenyl C71-butyric acid methyl ester (C70PCBM) (ADS71BFA) as fullerene derivatives and 2.5 parts by weight of polymer compounds 2 and 2 as electron donor compounds .5 parts by weight of the polymer compound 3 and 1000 parts by weight of o-dichlorobenzene as a solvent were mixed. Thereafter, the liquid obtained by mixing was filtered through a Teflon (registered trademark) filter having a pore diameter of 1.0 μm to produce a coating solution 1.

(Production of coating solution 2)
5 parts by weight of [6,6] -phenyl C61-butyric acid methyl ester (PCBM) (frontier carbon, E100H) as a fullerene derivative, 2.5 parts by weight of polymer compound 1 as an electron donor compound, and a solvent 1000 parts by weight of chloroform and 50 parts by weight of o-dichlorobenzene were mixed. Thereafter, the liquid obtained by mixing was filtered through a Teflon (registered trademark) filter having a pore diameter of 1.0 μm to produce a coating solution 2.

(Production of coating solution 3)
5 parts by weight of [6,6] -phenyl C61-butyric acid methyl ester (PCBM) (E100H, manufactured by Frontier Carbon Co.) as a fullerene derivative, 2.5 parts by weight of polymer compound 4 as an electron donor compound, and a solvent As 1000 parts by weight of o-dichlorobenzene. Thereafter, the liquid obtained by mixing was filtered through a Teflon (registered trademark) filter having a pore diameter of 1.0 μm to produce a coating solution 3.

<Example 1>
(Production of organic thin film solar cells)
A glass substrate provided with an ITO film with a thickness of 150 nm by a sputtering method was subjected to surface treatment by ozone UV treatment. Next, a PEDOT: PSS solution (manufactured by HC Starck, CleviosP VP AI4083) is applied onto the ITO film by spin coating, and heated in the atmosphere at 120 ° C. for 10 minutes to form a hole with a thickness of 50 nm. An injection layer was produced. Next, the coating solution 1 was applied onto the ITO film by spin coating to obtain an active layer 1 of an organic thin film solar cell. The thickness of the active layer 1 was 200 nm. Thereafter, an ethylene glycol monobutyl ether dispersion of 40% by weight of zinc oxide nanoparticles (average particle size of 35 nm or less, maximum particle size of 120 nm or less, manufactured by Sigma-Aldrich Japan) was further diluted with 3 times by weight of ethylene glycol monobutyl ether. Using the coating liquid, spin coating applied to the active layer 1 with a film thickness of 190 nm to obtain an electron transport layer. Thereafter, a neutral PEDOT: PSS dispersion (Clevios PH1000N, manufactured by HC Starck Co., Ltd.) having a thickness of 100 nm was applied on the electron transport layer by spin coating to obtain a hole transport layer. It was. Then, the said application | coating solution 2 was apply | coated with the film thickness of 100 nm on the positive hole transport layer by spin coating, and the active layer 2 of the organic thin-film solar cell was obtained. Then, the organic thin film solar cell was produced by vapor-depositing calcium with a film thickness of 4 nm with a vacuum evaporation machine, and vapor-depositing aluminum with a film thickness of 100 nm. The degree of vacuum at the time of vapor deposition was 1 to 9 × 10 ⁻³ Pa in all cases. The shape of the organic thin film solar cell thus obtained was a square of 2 mm × 2 mm. The obtained organic thin film solar cell is irradiated with a certain amount of light using a solar simulator (trade name: OTENTO-SUNII: AM1.5G filter, irradiance: 100 mW / cm ² ), and the generated current and voltage are measured. did. The photoelectric conversion efficiency is 6.4%, Jsc (short circuit current density) is 9.7 mA / cm ² , Voc (open end voltage) is 1.35 V, and FF (fill factor) is 0.49. there were.

<Example 2>
(Production of organic thin film solar cells)
A glass substrate provided with an ITO film with a thickness of 150 nm by a sputtering method was subjected to surface treatment by ozone UV treatment. Next, a PEDOT: PSS solution (manufactured by HC Starck, CleviosP VP AI4083) is applied onto the ITO film by spin coating, and heated in the atmosphere at 120 ° C. for 10 minutes to form a hole with a thickness of 50 nm. An injection layer was produced. Next, the coating solution 1 was applied onto the ITO film by spin coating to obtain an active layer 1 of an organic thin film solar cell. The thickness of the active layer 1 was 200 nm. Thereafter, an isopropanol dispersion of 45% by weight of zinc oxide nanoparticles (HTD-711Z, manufactured by Teica) was further spin-coated on the active layer 1 by using a coating solution diluted with 5-fold parts by weight of 2-propanol. An electron transport layer was obtained by coating with a film thickness of 130 nm. After that, a neutral PEDOT: PSS dispersion (pH C: manufactured by HC Starck Co., Ltd., Clevios PH1000N) diluted with 1 part by weight of ultrapure water was spin coated on the electron transport layer. The film was applied to a thickness of 30 nm to obtain a hole transport layer. Then, the said application | coating solution 3 was apply | coated with the film thickness of 110 nm on the positive hole transport layer by spin coating, and the active layer 2 of the organic thin-film solar cell was obtained. Then, the organic thin film solar cell was produced by vapor-depositing calcium with a film thickness of 4 nm with a vacuum evaporation machine, and vapor-depositing aluminum with a film thickness of 100 nm. The degree of vacuum at the time of vapor deposition was 1 to 9 × 10 ⁻³ Pa in all cases. The shape of the organic thin film solar cell thus obtained was a square of 4 mm × 4 mm. The obtained organic thin film solar cell is irradiated with a certain amount of light using a solar simulator (trade name: OTENTO-SUNII: AM1.5G filter, irradiance: 100 mW / cm ² ), and the generated current and voltage are measured. did. The photoelectric conversion efficiency is 8.2%, Jsc (short circuit current density) is 8.2 mA / cm ² , Voc (open circuit voltage) is 1.56 V, and FF (fill factor) is 0.59. there were.

<Comparative Example 1>
(Production of organic thin film solar cells)
A glass substrate provided with an ITO film with a thickness of 150 nm by a sputtering method was subjected to surface treatment by ozone UV treatment. Next, PEDOT: PSS solution (manufactured by HC Starck, CleviosP VP AI4083) is applied on the ITO film by spin coating, and heated at 120 ° C. in the atmosphere for 10 minutes to inject holes with a thickness of 50 nm. A layer was made. Next, the coating solution 1 was applied onto the ITO film by spin coating to obtain an active layer of an organic thin film solar cell. The thickness of the active layer was 200 nm. Then, the organic thin film solar cell was produced by vapor-depositing calcium with a film thickness of 4 nm with a vacuum evaporation machine, and vapor-depositing aluminum with a film thickness of 100 nm. The degree of vacuum at the time of vapor deposition was 1 to 9 × 10 ⁻³ Pa in all cases. The shape of the organic thin film solar cell thus obtained was a square of 2 mm × 2 mm. The obtained organic thin film solar cell is irradiated with a certain amount of light using a solar simulator (trade name: OTENTO-SUNII: AM1.5G filter, irradiance: 100 mW / cm ² ), and the generated current and voltage are measured. did. The photoelectric conversion efficiency is 6.0%, Jsc (short circuit current density) is 11.3 mA / cm ² , Voc (open circuit voltage) is 0.89 V, and FF (fill factor) is 0.60. there were.

<Comparative example 2>
(Production of organic thin film solar cells)
A glass substrate provided with an ITO film with a thickness of 150 nm by a sputtering method was subjected to surface treatment by ozone UV treatment. Next, PEDOT: PSS solution (manufactured by HC Starck, CleviosP VP AI4083) is applied on the ITO film by spin coating, and heated at 120 ° C. in the atmosphere for 10 minutes to inject holes with a thickness of 50 nm. Created a layer. Next, the coating solution 2 was applied onto the ITO film by spin coating to obtain an active layer of an organic thin film solar cell. The thickness of the active layer was 100 nm. Then, the organic thin film solar cell was produced by vapor-depositing calcium with a film thickness of 4 nm with a vacuum evaporation machine, and vapor-depositing aluminum with a film thickness of 100 nm. The degree of vacuum at the time of vapor deposition was 1 to 9 × 10 ⁻³ Pa in all cases. The shape of the organic thin film solar cell thus obtained was a square of 2 mm × 2 mm. The obtained organic thin film solar cell is irradiated with a certain amount of light using a solar simulator (trade name: OTENTO-SUNII: AM1.5G filter, irradiance: 100 mW / cm ² ), and the generated current and voltage are measured. did. The photoelectric conversion efficiency is 3.4%, Jsc (short circuit current density) is 11.6 mA / cm ² , Voc (open end voltage) is 0.54 V, and FF (fill factor) is 0.54. there were.

<Comparative Example 3>
(Production of organic thin film solar cells)
A glass substrate provided with an ITO film with a thickness of 150 nm by a sputtering method was subjected to surface treatment by ozone UV treatment. Next, PEDOT: PSS solution (manufactured by HC Starck, CleviosP VP AI4083) is applied on the ITO film by spin coating, and heated at 120 ° C. in the atmosphere for 10 minutes to inject holes with a thickness of 50 nm. Created a layer. Next, the coating solution 3 was applied on the ITO film by spin coating to obtain an active layer of an organic thin film solar cell. The thickness of the active layer was 110 nm. Then, the organic thin film solar cell was produced by vapor-depositing calcium with a film thickness of 4 nm with a vacuum evaporation machine, and vapor-depositing aluminum with a film thickness of 100 nm. The degree of vacuum at the time of vapor deposition was 1 to 9 × 10 ⁻³ Pa in all cases. The shape of the organic thin film solar cell thus obtained was a square of 4 mm × 4 mm. The obtained organic thin film solar cell is irradiated with a certain amount of light using a solar simulator (trade name: OTENTO-SUNII: AM1.5G filter, irradiance: 100 mW / cm ² ), and the generated current and voltage are measured. did. The photoelectric conversion efficiency is 6.0%, Jsc (short circuit current density) is 14.7 mA / cm ² , Voc (open circuit voltage) is 0.70 V, and FF (fill factor) is 0.58. there were.

Claims (6)

An organic photoelectric conversion element configured by laminating a plurality of active layers and a joined body positioned between the active layers between a pair of electrodes,
The joined body contains a plurality of layers including an electron transport layer and a hole transport layer,
By applying the coating liquid containing the electron transporting material and the solvent represented by the formula (1a) or the solvent represented by the formula (1b) on the layer below the electron transporting layer. Organic photoelectric conversion element to be formed.

(1a) (1b)
[Wherein, n represents an integer of 2 to 5, and R represents an alkyl group having 1 to 10 carbon atoms. ]   The organic photoelectric conversion element according to claim 1, wherein the electron transporting material contains particles made of zinc oxide.   The hole transport layer is formed by applying a coating solution containing a hole transport material and a solvent and having a pH of 3 to 9 on a layer below the hole transport layer. The organic photoelectric conversion element as described.   The organic photoelectric conversion element as described in any one of Claims 1-3 in which an active layer contains a conjugated polymer compound and a fullerene derivative. Manufacture of an organic photoelectric conversion element configured by laminating a plurality of active layers and a joined body including a plurality of layers located between the active layers and including an electron transport layer and a hole transport layer, between a pair of electrodes A method,
The electron transport layer is formed by applying a coating liquid containing an electron transport material and a solvent represented by the formula (1a) or a solvent represented by the formula (1b) on a layer below the electron transport layer. A method for producing an organic photoelectric conversion element.

(1a) (1b)
[Wherein, n represents an integer of 2 to 5, and R represents an alkyl group having 1 to 10 carbon atoms. ]   6. The production according to claim 5, wherein the hole transport layer is formed by coating a coating solution containing a hole transport material and a solvent and having a pH of 3 to 9 on a layer below the hole transport layer. Method.