Condensed polycyclic aromatic compound and photoelectric conversion element material

Abstract

To provide a condensed polycyclic aromatic compound that serves as an organic photoelectric conversion material that is excellent in external quantum yield (EQE) and response speed when used in a photoelectric conversion element, as well as a photoelectric conversion element material, an organic thin film, and an organic photoelectric conversion element that use the same.SOLUTION: A condensed polycyclic aromatic compound is represented by the following formula (1) (in formula (1), X and Y each independently represent a divalent aromatic hydrocarbon group or a single bond).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a novel fused polycyclic aromatic compound and its use. More specifically, the present invention relates to a fused polycyclic aromatic compound which is a benzothieno[2,3-d]naphtho[2,3-b]thiophene (hereinafter referred to as "BTNT") derivative, and a photoelectric conversion element material, an organic thin film, an organic photoelectric conversion element, a solar cell, an optical sensor, an imaging element, a photocounter, and a LIDAR using the same. [Background technology]

[0002] Organic electronics devices have been actively researched and developed in recent years because they can be supplied stably as they do not contain rare metals in the raw materials, have flexibility not found in inorganic materials, and can be manufactured by wet film formation. For example, organic thin-film devices such as organic electroluminescence (EL) elements, field effect transistors, and organic photoelectric conversion elements have attracted attention, and various organic electronics materials, such as condensed polycyclic aromatic compounds, used in these thin-film devices have been researched and developed.

[0003] Among the above devices, organic photoelectric conversion elements are used in optical sensors, etc., and their use in, for example, imaging elements is being considered (Patent Document 1). In addition, the use of BTNT compounds, which are known to exhibit high hole mobility, as organic photoelectric conversion materials is being considered (Patent Documents 2 and 3).

[0004] When using organic photoelectric conversion materials as imaging elements, there is a demand for improved external quantum efficiency (hereinafter abbreviated as EQE), which indicates the degree to which irradiated light is efficiently converted into electrical energy, and for the imaging element to have a high response speed when switching light irradiation ON / OFF in order to clearly capture a moving object (Patent Document 4). In order to satisfy such required characteristics, organic photoelectric conversion elements are currently being researched with a bulk heterojunction structure in which the photoelectric conversion layer is made of a mixed film of a P-type organic semiconductor and an N-type organic semiconductor, and studies are being conducted to achieve both a high EQE and high response. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] WO2022 / 114065 [Patent Document 2] JP 2023-038556 A [Patent Document 3] JP 2023-114007 A [Patent Document 4] JP 2015-032711 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the inventors' evaluation revealed that none of the photoelectric conversion elements using BTNT compounds reported so far could simultaneously satisfy both the EQE and the response speed.

[0007] In view of the above circumstances, the present invention aims to provide a condensed polycyclic aromatic compound that serves as an organic photoelectric conversion material excellent in external quantum efficiency (EQE) and response speed when used as a photoelectric conversion element, as well as a photoelectric conversion element material, an organic thin film, and an organic photoelectric conversion element using the same. [Means for solving the problem]

[0008] As a result of intensive research, the present inventors have found that the above problems can be solved by using a novel fused polycyclic aromatic compound in which a thiophene ring bonded at the 3-position is arranged at the molecular end, thereby completing the present invention.

[0009] That is, the present invention provides: [1] The following formula (1)

[0010] [ka] (In the formula (1), X and Y each independently represent a divalent aromatic hydrocarbon group or a single bond.)

[0011] [2] The condensed polycyclic aromatic compound according to the above [1], wherein X and Y are the same. [3] The condensed polycyclic aromatic compound according to the above [1], wherein X and Y are different from each other. [4] The condensed polycyclic aromatic compound according to any one of the above [1] to [3], wherein X and Y each independently represent a divalent linking group obtained by removing two hydrogen atoms from benzene, biphenyl, terphenyl, or naphthalene. [5] A photoelectric conversion element material containing the fused polycyclic aromatic compound according to [1] above. [6] An organic thin film comprising the condensed polycyclic aromatic compound according to the above [1] or the photoelectric conversion element material according to the above [5]. [7] An organic photoelectric conversion element having the organic thin film according to [6] above. Regarding. Effect of the Invention

[0012] The present invention can provide a fused polycyclic aromatic compound that serves as an organic photoelectric conversion material that is excellent in external quantum efficiency (EQE) and response speed when used as a photoelectric conversion element, as well as a photoelectric conversion element material, an organic thin film, and an organic photoelectric conversion element using the same. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic cross-sectional view showing one embodiment of an organic photoelectric conversion element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] [Fused polycyclic aromatic compound] The condensed polycyclic aromatic compound of the present invention is represented by the following formula (1).

[0015] [ka]

[0016] In formula (1), X and Y each independently represent a divalent aromatic hydrocarbon group or a single bond. When one of X and Y represents a divalent aromatic hydrocarbon group and the other represents a single bond, it is preferable that X represents a divalent aromatic hydrocarbon group and Y represents a single bond. More preferably, both X and Y each independently represent a divalent aromatic hydrocarbon group. The divalent aromatic hydrocarbon group is a divalent linking group obtained by removing any two hydrogen atoms from the aromatic ring of an aromatic hydrocarbon compound. The carbon number of the aromatic hydrocarbon compound that can be a divalent linking group is preferably 24 or less as the total value of X and Y, more preferably 6 to 18, and even more preferably 12 to 18. The aromatic hydrocarbon compound that can be a divalent linking group is not particularly limited as long as it is a hydrocarbon compound having aromaticity. Examples include linking groups obtained by removing two hydrogen atoms from aromatic organic compounds selected from benzene, naphthalene, biphenyl, anthracene, terphenyl, phenanthrene, tetracene, chrysene, pyrene, fluorene, phenylnaphthalene, and diphenylnaphthalene. Among them, divalent linking groups obtained by removing two hydrogen atoms from benzene, naphthalene, biphenyl, anthracene, terphenyl, or phenylnaphthalene are preferred, divalent linking groups obtained by removing two hydrogen atoms from benzene, naphthalene, biphenyl, or terphenyl are more preferred, and in the case of biphenyl or terphenyl, divalent linking groups obtained by removing two hydrogen atoms from p-biphenyl or p-terphenyl are even more preferred. The divalent aromatic hydrocarbon group may have a substituent, and the substituent that may be present is not particularly limited. In addition, when X and Y are single bonds, it means that a thiophene ring is directly bonded to the BTNT ring.

[0017] The three carbon atoms on the two thiophene rings at the ends of the molecule in formula (1) may have substituents, but preferably have no substituents, and the thiophene rings do not have any further condensed ring structure.

[0018] Next, a method for synthesizing the fused polycyclic aromatic compound represented by formula (1) will be described. The compound represented by formula (1) can be synthesized by the same reaction steps as in known methods (for example, Japanese Patent No. 6161168).

[0019] An example of a synthesis flow for the compound represented by formula (1) is described below. In the following flow, X and Y have the same meanings as X and Y in formula (1), Me represents a methyl group, and TMS represents a trimethylsilyl group.

[0020] [ka]

[0021] The method for purifying the condensed polycyclic aromatic compound represented by formula (1) is not particularly limited, and known methods such as recrystallization, column chromatography, and vacuum sublimation purification can be used. Furthermore, these methods can be combined as necessary.

[0022] Specific examples of the fused polycyclic aromatic compound represented by formula (1) are shown below, but the invention is not limited to these specific examples.

[0023] [ka]

[0024] [Photoelectric conversion element materials] The photoelectric conversion element material contains a condensed polycyclic aromatic compound represented by formula (1). The photoelectric conversion element material may contain components other than the compound represented by formula (1) as long as the effects of the present invention are not impaired, but it is preferable that the photoelectric conversion element material contains only the compound represented by formula (1). The content of the compound represented by formula (1) in the photoelectric conversion element material is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, particularly preferably 98% by mass or more, and most preferably 99% by mass or more. The photoelectric conversion element material may contain one or more types of fused polycyclic aromatic compounds represented by formula (1). A photoelectric conversion element material containing the fused polycyclic aromatic compound represented by formula (1) can be used as a hole transport material in a photoelectric conversion element to realize a photoelectric conversion element with an excellent response speed.

[0025] [Organic thin film] The organic thin film of the present invention is characterized by including the photoelectric conversion element material of the present invention. The thickness of the organic thin film may be selected depending on the application, but is usually 1 nm to 1 μm, preferably 5 nm to 500 nm, and more preferably 10 nm to 500 nm. Methods for forming the organic thin film include dry processes such as deposition (methods using the photoelectric conversion element material as it is) and various solution processes (methods using a solution in which the photoelectric conversion element material is dissolved and / or dispersed in an organic solvent or the like). Examples of solution processes include letterpress printing methods such as spin coating, drop casting, dip coating, spraying, flexographic printing, and resin letterpress printing, lithographic printing methods such as offset printing, dry offset printing, and pad printing, intaglio printing methods such as gravure printing, stencil printing methods such as screen printing, mimeograph printing, and ring graph printing, inkjet printing, microcontact printing, and the like, as well as methods combining a plurality of these methods. When forming a film by a solution process, it is preferable to form a thin film by evaporating the solvent after carrying out the above-mentioned coating or printing.

[0026] The organic thin film of the present invention has electron transport properties or hole transport properties, and therefore can be used in organic semiconductor elements such as organic transistors and organic photoelectric conversion elements (organic thin film solar cells, photosensors, imaging elements, photocounters, LIDAR, etc.) by controlling the transport of electrons or holes injected from an electrode, or charges generated by absorbed light.

[0027] [Organic photoelectric conversion element] An organic photoelectric conversion element is an element composed of an organic semiconductor material and electrodes, etc., and is an element that converts light into electricity. FIG. 1 shows an example of an organic photoelectric conversion element. An organic photoelectric conversion element 7 includes a substrate 1, a first electrode 2, an electron blocking layer 3, a photoelectric conversion layer 4, a hole blocking layer 5, and a second electrode 6, in this order. An organic photoelectric conversion element 10 is characterized in that both or one of the electron blocking layer 3 and the photoelectric conversion layer 4 have an organic thin film containing the photoelectric conversion element material of the present invention as a hole transport material. The organic photoelectric conversion element of the present invention is not limited to the structure of FIG. 1, and layers can be added or omitted as necessary.

[0028] -Substrate 1- The substrate 1 is a member that supports the organic photoelectric conversion element 7. There is no particular limitation on the material of the substrate 1, and for example, a material made of glass, transparent plastic, quartz, or the like can be used. In addition, when light is incident from the second electrode 6 side in FIG. 1, the substrate 1 does not necessarily have to be transparent. Here, "transparent" means that the transmittance of light of a specific wavelength to be converted into a current is excellent. In addition, a substrate may be further disposed outside the second electrode 6, but at least one of the substrate 1 and the substrate outside the second electrode 6 must be transparent.

[0029] -First electrode 2, second electrode 6- The first electrode 2 and the second electrode 6 have a function of collecting holes and electrons generated in the photoelectric conversion layer 4. Since a function of allowing light to enter the photoelectric conversion layer 4 is also required, at least one of the first electrode 2 and the second electrode 6 must be transparent. The material of the first electrode 2 and the second electrode 6 is not particularly limited as long as it has conductivity, and examples thereof include conductive transparent materials such as ITO, IZO, SnO2, ATO (antimony-doped tin oxide), ZnO, AZO (Al-doped zinc oxide), GZO (gallium-doped zinc oxide), TiO2, and FTO, metals such as gold, silver, platinum, chromium, aluminum, iron, cobalt, nickel, and tungsten, inorganic conductive materials such as copper iodide and copper sulfide, and conductive polymers such as polythiophene, polypyrrole, and polyaniline. The first electrode 2 and the second electrode 6 may contain a mixture of a plurality of these materials as necessary, or may be a laminate of two or more layers.

[0030] -Electron Block Layer 3- The electron blocking layer 3 is provided to suppress dark current generated when electrons are injected from one electrode into the photoelectric conversion layer 4 when a bias voltage is applied between the two electrodes. It also has a function as a hole transporter that transports holes generated by charge separation in the photoelectric conversion layer 4 to the electrode. The electron blocking layer 3 may be a single layer or multiple layers, as necessary.

[0031] The electron blocking layer 3 may contain a P-type organic semiconductor material that is a hole transporting material. As the P-type organic semiconductor material, the photoelectric conversion element material of the present invention and the organic thin film of the present invention are preferable, but other P-type organic semiconductor materials may also be used.

[0032] Other p-type organic semiconductor materials that can be used include, for example, compounds having a condensed polycyclic aromatic group such as naphthalene, anthracene, phenanthrene, pyrene, chrysene, naphthacene, triphenylene, perylene, fluoranthene, fluorene, and indene, compounds having a π-electron-rich aromatic group such as cyclopentadiene derivatives, furan derivatives, thiophene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, dinaphthothienothiophene derivatives, indole derivatives, pyrazoline derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, and carbazole derivatives, as well as aromatic amine derivatives, styrylamine derivatives, benzidine derivatives, porphyrin derivatives, phthalocyanine derivatives, and quinacridone derivatives.

[0033] -Photoelectric conversion layer 4- The photoelectric conversion layer 4 is a layer in which holes and electrons are generated by charge separation of excitons generated by incident light. The photoelectric conversion layer 4 may be formed only of a photoelectric conversion element material, but may be formed in combination with a P-type organic semiconductor material that is a hole transport material or an N-type organic semiconductor material that is an electron transport material. In addition, two or more types of P-type organic semiconductor materials may be used, or two or more types of N-type organic semiconductor materials may be used. It is desirable that one or more of the photoelectric conversion element material, P-type organic semiconductor material, and N-type organic semiconductor material contained in the photoelectric conversion layer 4 contain a dye material having a function of absorbing light of a desired wavelength in the visible region. It is a preferred embodiment to use the photoelectric conversion element material of the present invention and the organic thin film of the present invention as the P-type organic semiconductor material that is a hole transport material.

[0034] The photoelectric conversion element material may be any material that generates excitons in response to incident light, and examples of the material that can be used include compounds having a condensed polycyclic aromatic group such as naphthalene, anthracene, phenanthrene, pyrene, chrysene, naphthacene, triphenylene, perylene, fluoranthene, fluorene, and indene; compounds having a π-electron-rich aromatic group such as cyclopentadiene derivatives, furan derivatives, thiophene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, dinaphthothienothiophene derivatives, indole derivatives, pyrazoline derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, carbazole derivatives, and indolocarbazole derivatives; aromatic amine derivatives, styrylamine derivatives, benzidine derivatives, porphyrin derivatives, phthalocyanine derivatives, and quinacridone derivatives. From the viewpoint of the efficiency of using incident light, a material with a high absorption coefficient is preferable, and for example, pyrromethene derivatives, porphyrin derivatives, subporphyrin derivatives, phthalocyanine derivatives, subphthalocyanine derivatives, quinacridone derivatives, pyrrolopyrrole derivatives, coumarin derivatives, perylene derivatives, and aromatic amine derivatives can be used.

[0035] When the above photoelectric conversion element material is used as the P-type organic semiconductor material, it may be used in combination with another P-type organic semiconductor material, and two or more of the above photoelectric conversion element materials may be used. Other p-type organic semiconductor materials that can be used include, for example, compounds having a condensed polycyclic aromatic group such as naphthalene, anthracene, phenanthrene, pyrene, chrysene, naphthacene, triphenylene, perylene, fluoranthene, fluorene, and indene; compounds having a π-electron-rich aromatic group such as cyclopentadiene derivatives, furan derivatives, thiophene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, dinaphthothienothiophene derivatives, indole derivatives, pyrazoline derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, carbazole derivatives, and indolocarbazole derivatives; aromatic amine derivatives, styrylamine derivatives, benzidine derivatives, porphyrin derivatives, phthalocyanine derivatives, and quinacridone derivatives. Examples of the polymeric P-type organic semiconductor material include polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, and polythiophene derivatives. The polymeric P-type organic semiconductor material may be mixed with the photoelectric conversion element material of the present invention or a non-polymeric P-type organic semiconductor material, or two or more polymeric P-type organic semiconductor materials may be mixed together.

[0036] The N-type organic semiconductor material may be any material having electron transport properties, and examples thereof include naphthalenetetracarboxylic acid diimide, perylenetetracarboxylic acid diimide, fullerenes, and azole derivatives such as imidazole, thiazole, thiadiazole, oxazole, oxadiazole, and triazole. One or a combination of two or more selected from these N-type organic semiconductor materials may be used.

[0037] -Hole blocking layer 5- The hole blocking layer 5 is provided to suppress a dark current generated by holes being injected from one electrode into the photoelectric conversion layer 4 when a bias voltage is applied between the two electrodes. The hole blocking layer 5 also functions as an electron transport layer that transports electrons generated by charge separation in the photoelectric conversion layer 4 to the electrode. The hole blocking layer 5 may have a single layer or multiple layers as necessary. The hole blocking layer 5 may be made of an N-type organic semiconductor material having electron transport properties. The N-type organic semiconductor material may be any material having electron transport properties, and examples thereof include polycyclic aromatic polycarboxylic anhydrides such as naphthalene tetracarboxylic diimide and perylene tetracarboxylic diimide, and imidized products thereof, fullerenes such as C60 and C70, azole derivatives such as imidazole, thiazole, thiadiazole, oxazole, oxadiazole, and triazole, tris(8-quinolinolato)aluminum(III) derivatives, phosphine oxide derivatives, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidene methane derivatives, anthraquinodimethane and anthrone derivatives, bipyridine derivatives, quinoline derivatives, and indolocarbazole derivatives. One or a combination of two or more selected from these N-type organic semiconductor materials may be used. EXAMPLES

[0038] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The structures of the compounds described in the synthesis examples were determined by mass spectrometry and nuclear magnetic resonance spectrometry (NMR) as necessary. The 1H NMR measurements in the examples were performed using a JNM-ECS400 (manufactured by JEOL), and the molecular weight measurements were performed using an ISQ LT GC-MS (manufactured by Thermo Fisher Scientific).

[0039] [Example 1: Synthesis of compound (1-1) of the present invention] In a nitrogen atmosphere, PdCl2(PPh3)2 (14 mg, 0.02 mmol) was added to a degassed solution of intermediate (2-1) (0.4 mmol) and NaOAc (67 mg, 0.8 mmol) in DMAc (14 ml) in a container, and the mixture was stirred at 140°C for 15 hours. The reaction solution obtained above was cooled to room temperature, and the resulting solid was filtered and washed with water and acetone. The crude product obtained above was then purified by sublimation to obtain a yellow solid of compound (1-1). (Yield 20%) The molecular weight of the compound represented by compound (1-1) obtained above was measured, and the results were as follows. EI-MS(m / z):606[M]+

[0040] [ka]

[0041] [Example 2: Synthesis of compound (1-2) of the present invention] In a nitrogen atmosphere, PdCl2(PPh3)2 (14 mg, 0.02 mmol) was added to a degassed solution of intermediate (2-2) (0.4 mmol) and NaOAc (67 mg, 0.8 mmol) in DMAc (14 ml) in a container, and the mixture was stirred at 140°C for 15 hours. The reaction solution obtained above was cooled to room temperature, and the resulting solid was filtered and washed with water and acetone. The crude product obtained above was then purified by sublimation to obtain a yellow solid of compound (1-2). (Yield 23%) The molecular weight of the compound represented by compound (1-2) obtained above was measured, and the results were as follows. EI-MS(m / z):706[M]+

[0042] [ka]

[0043] [Example 3: Synthesis of Compound (1-6) of the Present Invention] In a nitrogen atmosphere, PdCl2(PPh3)2 (14 mg, 0.02 mmol) was added to a degassed solution of intermediate (2-3) (0.4 mmol) and NaOAc (67 mg, 0.8 mmol) in DMAc (14 ml) in a container, and the mixture was stirred at 140°C for 15 hours. The reaction solution obtained above was cooled to room temperature, and the resulting solid was filtered and washed with water and acetone. The crude product obtained above was then purified by sublimation to obtain a yellow solid of compound (1-6). (Yield 25%) The molecular weight of the compound represented by compound (1-6) obtained above was measured, and the results were as follows. EI-MS(m / z):606[M]+

[0044] [ka]

[0045] [Synthesis of Comparative Compounds (3-1) and (3-2)] Comparative compounds (3-1) and (3-2) were synthesized by known methods.

[0046] [ka]

[0047] [Example 4: Preparation of photoelectric conversion element A] A blocking layer was formed on a glass substrate with an ITO electrode having a thickness of 70 nm. The substrate temperature was room temperature and the vacuum degree was 4.0×10 -5 Under the condition of 10 Pa, CzBDF (manufactured by Tokyo Chemical Industry Co., Ltd.) was formed to a thickness of 10 nm. Next, as a photoelectric conversion layer, the compound (1-1) obtained in Example 1, Cl6-SubPc-OPh (manufactured by Lumitec Co., Ltd.) and fullerene (C60, manufactured by Tokyo Chemical Industry Co., Ltd.) were co-evaporated at a deposition rate ratio of 4:4:2 to form an organic thin film having a thickness of 230 nm. Subsequently, 10 nm of commonly available dpy-NDI (manufactured by Tokyo Chemical Industry Co., Ltd.) was evaporated to form a hole blocking layer. Finally, aluminum was deposited to a thickness of 100 nm as an electrode to prepare a photoelectric conversion element A.

[0048] [ka]

[0049] [Example 5: Preparation of photoelectric conversion element B] A photoelectric conversion element B was prepared in the same manner as in Example 3, except that the compound (1-2) obtained in Example 2 was used instead of the compound (1-1).

[0050] [Example 6: Preparation of photoelectric conversion element C] A photoelectric conversion element C was prepared in the same manner as in Example 3, except that the compound (1-6) obtained in Example 3 was used instead of the compound (1-1).

[0051] [Comparative Examples 1 and 2: Preparation of Photoelectric Conversion Elements P and Q] Comparative photoelectric conversion elements P and Q were prepared by the same procedure as in Example 3, except that comparative compound (3-1) and comparative compound (3-2), respectively, were used instead of the compound represented by compound (1-1).

[0052] (Evaluation of organic photoelectric conversion element) The EQE of the photoelectric conversion element was evaluated based on the example of WO2018-105269. Specifically, the EQE of each of the photoelectric conversion elements A to C, P, and Q was 2.0 × 10 5 A voltage was applied to the sample so that the intensity was 1000 V / cm, and the EQE of the photoelectric conversion at 550 nm was measured. The results are shown in Table 1. Evaluation criteria 95% or more: "A" If it is between 90% and 95%, it is classified as "B". If it is between 85% and 90%, it is classified as "C". If less than 85%, "D" In practice, the higher the EQE, the more efficiently irradiated light is converted into electrical energy, so "A" means the best and "D" means the worst.

[0053] [Table 1]

[0054] (Response speed evaluation) The response speed was evaluated based on the examples in WO2018-105269. Specifically, each photoelectric conversion element was charged with 2.0 × 10 5 A voltage was applied so that the intensity was 1000 V / cm. Then, an LED (light emitting diode) was momentarily turned on to irradiate light from the lower electrode on the transparent conductive film (ITO) side, and the photocurrent at that time was measured with an oscilloscope to measure the rise time from 0 to 97% signal intensity. A relative value was then calculated when the rise time of the element of Comparative Example 2 was taken as 1. The results are shown in Table 2. Evaluation criteria The relative value of the rise time is compared with Comparative Example 2. If less than 0.6, select "A" If it is between 0.6 and 0.7, it is classified as "B". If it is 0.7 or more but less than 0.8, it is "C" If it is 0.8 or more but less than 1.0, it is "D". If it is 1.0 or more, it is "E" In practice, it is desirable for the photoelectric conversion element to have a fast photoresponse speed, i.e., for the photocurrent value to approach 100% in a short time after exposure to light, so "A" means the best and "E" means the worst.

[0055] [Table 2]

[0056] The results in Tables 1 and 2 show that the photoelectric conversion elements of Examples 4 to 6 using the compounds of the present invention have good EQE and good response speed. On the other hand, the photoelectric conversion elements of Comparative Examples 1 and 2 show lower EQE and response speed than the Examples. [Industrial Applicability]

[0057] By using the fused polycyclic aromatic compound represented by formula (1), it is possible to provide an organic semiconductor device (photoelectric conversion element, optical sensor, etc.) excellent in EQE and responsiveness. [Explanation of symbols]

[0058] 1 Board 2 First electrode 3. Electron Block Layer 4 Photoelectric conversion layer 5 Hole Blocking Layer 6 Second electrode 7. Organic photoelectric conversion element

Claims

1. The following formula (1) 【Chemistry 1】 (In formula (1), X and Y each independently represent a divalent aromatic hydrocarbon group or a single bond.)

2. The condensed polycyclic aromatic compound according to claim 1 , wherein X and Y are the same.

3. The condensed polycyclic aromatic compound according to claim 1 , wherein X and Y are different from each other.

4. 4. The condensed polycyclic aromatic compound according to claim 1, wherein X and Y are each independently a divalent linking group formed by removing two hydrogen atoms from benzene, biphenyl, terphenyl, or naphthalene.

5. A photoelectric conversion element material comprising the condensed polycyclic aromatic compound according to claim 1 .

6. An organic thin film comprising the condensed polycyclic aromatic compound according to claim 1 or the photoelectric conversion element material according to claim 5.

7. An organic photoelectric conversion element comprising the organic thin film according to claim 6 .

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