JP2005093572A - Photovoltaic element and photosensor provided therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic photovoltaic element which can be manufactured easily to enable wet type film forming, does not easily form pin-hole, assures higher stability and results in higher conversion efficiency, against the conventional organic/organic pn type photovoltaic element. <P>SOLUTION: The organic photovoltaic element laminates a transparent electrode 2, an electron accepting organic layer 3 an electron supplying organic layer 4 and a rear electrode 5 on a transparent insulating support material 1. The electron supplying organic layer 4 includes a polymer material, for example, expressed by the following formula. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a photovoltaic device and an optical sensor including the same.

  Many photovoltaic devices using organic substances as active materials have been studied. The purpose is to develop an inexpensive and non-toxic photovoltaic element that is difficult to achieve with single crystal, polycrystal, and amorphous Si.

  Since the photovoltaic element is an element that converts light energy into electric energy (voltage × current), conversion efficiency is a main evaluation target. The generation of a photocurrent requires the presence of an internal electric field, but several device configurations are known as methods for generating an internal electric field.

(1) Schottky junction or MIS type junction This element utilizes an internal electric field generated at a metal / semiconductor junction. Merocyanine dyes, phthalocyanine pigments and the like have been reported as organic semiconductor materials (Non-patent Document 1). Although this element can take a large open circuit voltage (Voc), since a metal material is used for the electrode, the light transmittance of the electrode is lowered. The actual light transmittance is at most 30%, usually around 10%. In addition, these materials have poor oxidation resistance. Therefore, it is not possible to create high conversion efficiency and stable characteristics in this element form.

(2) Heterogeneous pn junction using n-type inorganic semiconductor / p-type organic semiconductor junction This element utilizes an internal electric field generated when an n-type inorganic semiconductor / p-type organic semiconductor is joined. CdS, ZnO or the like is used as the n-type material. Merocyanine dyes, phthalocyanines and the like have been reported as p-type organic semiconductor materials (Non-patent Document 2). This element is limited in spectral sensitivity because charge generation is mainly performed in the organic layer. This is because the organic layer is usually formed from a single material, but there is currently no organic semiconductor having strong light absorption from 400 nm to 800 nm. Therefore, this element configuration can solve the problems of light transmittance of the light incident electrode and stability of the electrode, but high conversion efficiency cannot be expected because the spectral sensitivity region is narrow.

(3) Using an organic / organic hetero pn junction This element uses an electric field generated when an electron-accepting organic substance and an electron-donating organic substance are joined. As this electron-accepting organic substance, dyes such as malachite green, methyl violet and pyrylium, condensed polycyclic aromatic compounds such as flavanthrone and perylene pigment have been reported, and as electron-donating organic substances, phthalocyanine pigments, merocyanine dyes, etc. It has been reported (Non-Patent Document 3). It is currently the most desirable compared to the above two configurations. Light irradiation from a transparent electrode can be performed, and photocharge can be generated with two kinds of materials, so that spectral sensitivity can be increased. However, Tang's technology has the following drawbacks.

  That is, the electron donating organic substance and the electron accepting organic substance have problems such as photocurrent, open circuit voltage, stability, and the like, and pinholes are likely to be formed during film formation. In addition, since the electron-accepting organic material has spectral sensitivity in the short wavelength region and the electron-donating organic material has spectral sensitivity in the long wavelength region, the combination of layers is limited.

  Patent Document 1 below proposes a photovoltaic device using a specific diimidazole compound as an electron-donating organic substance or an electron-accepting organic substance. However, even in this device configuration, the combination of the electron donating organic substance and the electron accepting organic substance is not yet optimized, and further improvement in photoelectric conversion efficiency is required. In addition, since the material is a low-molecular compound, a vapor deposition process is mainly used in the device fabrication process, and there remains a problem that mass production and area increase are not easy.

A. K. Ghosh et al. Appl. Phys. 49, 5982 (1978) A. Hor et al .: Appl. Phys. Lett. , 42, 15 (1983) C. Tang: Appl. Phys. Lett. , 48, 183 (1986) Japanese Patent Laid-Open No. 5-21823

  The present invention has been made in view of the above-described conventional circumstances, and its purpose is that an organic / organic pn type photovoltaic device can be formed into a wet film, can be easily manufactured, and does not easily generate pinholes. Another object of the present invention is to provide an organic photovoltaic device having good stability and high conversion efficiency, and an optical sensor using the organic photovoltaic device.

  As a result of intensive studies to achieve the above object, the present inventors have found that a photovoltaic device containing a polymer material having a specific structural unit in an electron donating organic material layer is effective for the above object. The headline and the present invention were completed. The present invention includes the following inventions.

That is, in the photovoltaic device according to the invention of claim 1, an electron-accepting organic material layer and an electron-donating organic material layer that generate an internal electric field by bonding are laminated between two electrodes, at least one of which is translucent. In the photovoltaic device
The electron donating organic material layer contains at least a polymer material represented by the following general formula (1).

(Wherein R ¹ , R ² and R ³ each independently represents a halogen atom, a substituted or unsubstituted group, a group selected from a linear or branched alkyl group, an alkoxy group or an alkylthio group, and x, y , Z each independently represents an integer of 0 to 4, and when there are a plurality of R ¹ , R ² , R ³ , they may be the same or different, Ar is a substituted or unsubstituted aromatic hydrocarbon group Represents.)

  Here, as the polymer material represented by the general formula (1), those represented by the following general formulas (2) to (4) are preferable.

(Wherein R ¹ , R ² , R ³ and R ⁴ each independently represents a halogen atom, a substituted or unsubstituted group selected from a linear or branched alkyl group, an alkoxy group or an alkylthio group; w represents an integer of 0 to 5, x, y, and z each independently represent an integer of 0 to 4, and when there are a plurality of R ¹ , R ² , R ³ , and R ⁴ , they may be the same or different. It may be different.)

(Wherein R ¹ , R ² , R ³ , R ⁵ and R ⁶ are each independently a halogen atom, a substituted or unsubstituted group selected from a linear or branched alkyl group, an alkoxy group, or an alkylthio group. , U represents an integer from 0 to 5, v, x, y, and z each independently represent an integer from 0 to 4, and there are a plurality of R ¹ , R ² , R ³ , R ⁵ , and R ⁶ , respectively. They may be the same or different.)

(In the formula, R ¹ , R ² , R ³ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are each independently a halogen atom, substituted or unsubstituted, a linear or branched alkyl group, an alkoxy group or an alkylthio group. Represents a group selected from the group, t represents an integer of 0 to 3, s, x, y, z each independently represents an integer of 0 to 4, R ¹ , R ² , R ³ , R ⁷ , When there are a plurality of R ^{8 s} , they may be the same or different.)

In the polymer material of the general formula (1), at least one of R ¹ , R ² , and R ³ is a substituted or unsubstituted group having 1 to 18 carbon atoms, a linear or branched alkyl group, an alkoxy group, or It is preferably an alkylthio group.

The photovoltaic element according to the invention of claim 6 is:
In a photovoltaic device in which a transparent electrode, an electron-accepting organic material layer, an electron-donating organic material layer, and a back electrode are laminated in this order,
A polymer material represented by the general formula (1), a polymer material represented by the general formula (2), a polymer material represented by the general formula (3); Any one of the polymer materials represented by the general formula (4) is contained (see FIG. 1).

The photovoltaic device according to the invention of claim 7 is a photovoltaic device in which a transparent electrode, a translucent n-type inorganic semiconductor layer, an electron-accepting organic material layer, an electron-donating organic material layer, and a back electrode are laminated in this order. ,
A polymer material represented by the general formula (1), a polymer material represented by the general formula (2), a polymer material represented by the general formula (3); Any one of the polymer materials represented by the general formula (4) is contained (see FIG. 2).

The photovoltaic device according to the invention of claim 8 is a photovoltaic device in which a transparent electrode, an electron-accepting organic material layer, a first electron-donating organic material layer, a second electron-donating organic material layer, and a back electrode are laminated in this order. In
The second electron-donating organic material layer includes a polymer material represented by the general formula (1), a polymer material represented by the general formula (2), and a polymer represented by the general formula (3). Any one of the material and the polymer material represented by the general formula (4) is contained (see FIG. 3).

The photovoltaic element according to the invention of claim 9 comprises a transparent electrode, a translucent n-type inorganic semiconductor layer, an electron-accepting organic material layer, a first electron-donating organic material layer, a second electron-donating organic material layer, and a back electrode. In photovoltaic elements stacked in this order,
The second electron-donating organic material layer includes a polymer material represented by the general formula (1), a polymer material represented by the general formula (2), and a polymer represented by the general formula (3). Any one of the materials and the polymer material represented by the general formula (4) is contained (see FIG. 4).

  An optical sensor according to a tenth aspect of the invention includes the photovoltaic element according to any one of the first to ninth aspects.

  According to the present invention as described above, a photovoltaic device that is excellent in stability, hardly generates pinholes, can be formed into a wet film and can be easily manufactured, and a useful optical sensor using the photovoltaic device are provided. This is an excellent effect.

The present invention is described in further detail below.
The photovoltaic element of the present invention is characterized in that a polymer material having a specific structural unit is contained in the electron donating organic material layer. The polymer material used in the present invention is an organic semiconductor material represented by the general formula (1).

  The organic semiconductor material of the present invention may have a substituent on the aromatic ring. An alkyl group, an alkoxy group, etc. are mentioned from a viewpoint of the solubility improvement to a solvent. As the number of carbons in these substituents increases, the solubility will improve, but on the other hand, the carrier mobility will decrease, so select a substituent that will provide the desired properties within the range that does not impair the solubility. It is preferable to do. Examples of a suitable substituent in that case include an alkyl group having 1 to 25 carbon atoms, an alkoxy group, and an alkylthio group. More preferably, an alkyl group having 1 to 18 carbon atoms, an alkoxy group, or an alkylthio group is used. A plurality of the same substituents may be introduced, or a plurality of different substituents may be introduced. These alkyl groups and alkoxy groups or alkylthio groups are further halogen atoms, cyano groups, phenyl groups, hydroxyl groups, carboxyl groups, linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, alkoxy groups or alkylthio groups. A phenyl group substituted with a group may be contained.

  Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, i-propyl group, t-butyl group, s-butyl group, n-butyl group, i-butyl group, pentyl group, hexyl group, Heptyl, octyl, nonyl, decyl, 3,7-dimethyloctyl, 2-ethylhexyl, trifluoromethyl, 2-cyanoethyl, benzyl, 4-chlorobenzyl, 4-methylbenzyl, A cyclopentyl group, a cyclohexyl group, etc. can be mentioned as an example, As an alkoxy group and an alkylthio group, what made the alkoxy group and the alkylthio group by inserting an oxygen atom or a sulfur atom in the bond position of the said alkyl group is mentioned as an example. .

  The polymer (organic semiconductor material) is further improved in solubility in a solvent due to the presence of an alkyl group, an alkoxy group, or an alkylthio group. It is important to improve the solubility of these materials because the manufacturing tolerance of the film wet film forming process is increased. For example, the choice of coating solvent is expanded, the temperature range during solution preparation is expanded, the temperature and pressure range during solvent drying is expanded, and the high processability results in high purity and high uniformity. The possibility of obtaining a high-quality thin film increases.

  The substituted or unsubstituted aromatic hydrocarbon group in the general formula (1) may be either a monocyclic group or a polycyclic group (a condensed polycyclic group or a non-condensed polycyclic group). be able to. Examples thereof include a phenyl group, a naphthyl group, a pyrenyl group, a fluorenyl group, an azulenyl group, an anthryl group, a triphenylenyl group, a chrycenyl group, a biphenylyl group, and a terphenylyl group.

Moreover, these aromatic hydrocarbon groups may have a substituent shown below.
(1) Halogen atom, trifluoromethyl group, cyano group, nitro group.
(2) An unsubstituted or substituted alkyl group or alkoxy group having 1 to 25 carbon atoms.
(3) Aryloxy group. (An aryloxy group having a phenyl group or a naphthyl group as the aryl group is exemplified. This is an unsubstituted or substituted alkyl group having 1 to 25 carbon atoms, an unsubstituted or substituted alkoxy group having 1 to 25 carbon atoms, or A halogen atom may be contained as a substituent, specifically, a phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, 4-methylphenoxy group, 4-methoxyphenoxy group, 4-chlorophenoxy group, And 6-methyl-2-naphthyloxy group.
(4) An alkylthio group or an arylthio group. (Specific examples of the alkylthio group or arylthio group include a methylthio group, an ethylthio group, a phenylthio group, and a p-methylphenylthio group.)
(5) An alkyl-substituted amino group. (Specifically, diethylamino group, N-methyl-N-phenylamino group, N, N-diphenylamino group, N, N-di (p-tolyl) amino group, dibenzylamino group, piperidino group, morpholino group And a urolidyl group.)
(6) Acyl group. (Specific examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, a malonyl group, and a benzoyl group.)

  Of the polymers containing the repeating unit represented by the general formula (1), a more preferred first embodiment is represented by the general formula (2).

  Of the polymers containing the repeating unit represented by the general formula (1), a more preferred second embodiment is represented by the general formula (3).

  Of the polymers containing the repeating unit represented by the general formula (1), a more preferred third embodiment is represented by the general formula (4).

  The method for producing a polymer containing the repeating unit represented by the general formulas (1) to (4) includes, for example, a Wittig-Horner reaction using an aldehyde and a phosphonate, a Wittig reaction using an aldehyde and a phosphonium salt, A Heck reaction using a halide, a Ullmann reaction using an amine and a halide, and the like can be used, and they can be produced by a known method.

  In addition, the specific manufacturing method of the polymer which consists of a structural unit represented by said general formula (1)-(4) used by this invention is the specification of Japanese Patent Application No. 2003-35582 which the applicant of this application submitted, for example. The details are described in the book.

  The preferred molecular weights of the polymers represented by the above general formulas (1) to (4) are 1000 to 1000000 in terms of polystyrene-equivalent number average molecular weight, and more preferably 2000 to 500000. When the molecular weight is too small, cracks are generated and the film formability is deteriorated, resulting in poor practicality. On the other hand, when the molecular weight is too large, the solubility in a general organic solvent is deteriorated, the viscosity of the solution becomes high and the coating becomes difficult, which is also a practical problem.

  The semiconductor material of the present invention exhibits good solubility in various common organic solvents such as dichloromethane, tetrahydrofuran, chloroform, toluene, dichlorobenzene and xylene. Therefore, a solution having an appropriate concentration can be prepared using an appropriate solvent capable of dissolving the polymer material of the present invention, and a semiconductor thin film can be prepared by a wet film forming method using the solution.

  As a wet film forming method for forming an organic semiconductor layer, a thin film is formed by a known wet film forming technique such as a spin coating method, a dipping method, a blade coating method, a spray coating method, a casting method, an ink jet method, or a printing method. be able to. For these various film forming methods, an appropriate solvent is selected from the solvent types described above. The film thickness is preferably 50 to 3000 mm.

  In the present invention, any one of the polymer materials represented by the general formula (1) may be appropriately selected and used (used alone), but two or more may be used in combination. .

Examples of the polymer material used in the electron-donating organic layer other than the polymer material of the present invention include the following conventionally known materials.
(A) Poly-N-vinylcarbazole derivative, poly-γ-carbazolylethyl glutamate derivative, pyrene-formaldehyde condensate derivative, polyvinylpyrene, polyvinylphenanthrene, oxazole derivative, imidazole derivative, distyrylbenzene derivative, diphenethylbenzene derivative (Described in JP-A-9-127713),
(B) α-phenylstilbene derivatives (described in JP-A-9-297419),
(C) butadiene derivatives (described in JP-A-9-80783),
(D) hydrogenated butadiene (described in JP-A-9-80784),
(E) a diphenylcyclohexane derivative (described in JP-A-9-80772),
(F) Distyryltriphenylamine derivative (described in JP-A-9-222740),
(G) a diphenyl distyrylbenzene derivative (described in JP-A-9-265197 and JP-A-9-265201),
(H) a stilbene derivative (described in JP-A-9-211877),
(I) m-phenylenediamine derivatives (described in JP-A Nos. 9-304956 and 9-304957),
(J) a resorcin derivative (described in JP-A-9-329907),
(K) Triarylamine derivatives (JP-A 64-9964, JP-A-7-199503, JP-A-8-176293, JP-A-8-208820, JP-A-8-253568, JP-A-8-269446) JP-A-3-221522, JP-A-4-11627, JP-A-4-183719, JP-A-4-124163, JP-A-4-320420, JP-A-4-316543, JP-A-5-310904, JP-A-7-56374, JP-A-8-62864, US Pat. Nos. 5,428,090 and 5,486,439).

  Although the polymer material has been described above, a low molecular electron donating organic material may be included together with the polymer material of the present invention for the purpose of improving the photoelectric conversion efficiency. For this purpose, conventionally known low molecular electron donating organic materials can be used, and these low molecular electron donating organic materials can be used alone or in combination of two or more.

As a conventionally known low molecular electron donating organic material,
(11) α-phenylstilbene derivatives (described in JP-A-57-73075),
(12) Hydrazone derivatives (described in JP-A Nos. 55-154955, 55-156955, 55-52063, 56-81850, etc.),
(13) Triphenylmethane derivatives (described in Japanese Patent Publication No. 5-10983),
(14) Anthracene derivative (described in JP-A-51-94829),
(15) Oxazole derivatives, oxadiazole derivatives (described in JP-A-52-139065 and JP-A-52-139066),
(16) Imidazole derivatives, triphenylamine derivatives (described in JP-A-3-285960),
(17) Benzidine derivatives (described in Japanese Patent Publication No. 58-32372),
(18) Styryl derivatives (described in JP-A Nos. 56-29245 and 58-198043),
(19) Carbazole derivatives (described in JP-A-58-58552),
(20) Pyrene derivatives (described in JP-A-2-94812),
Etc.

  The present invention uses a specific polymer material for the electron donating organic layer in an organic / organic pn type photovoltaic device. Such a photovoltaic element is used, for example, in the form (laminated structure) shown in FIG. 1, FIG. 2, FIG. 3, and FIG.

In FIG. 1, a transparent electrode 2, an electron-accepting organic material layer 3, an electron-donating organic material layer 4 and a back electrode 5 are laminated on a transparent insulating support 1, and lead wires 6 are respectively connected to the transparent electrode 2 and the back electrode 5. Is attached.
FIG. 2 shows a transparent n-type inorganic semiconductor layer 7 provided between the transparent electrode 2 and the electron-accepting organic material layer 3 shown in FIG. The feature of this configuration is that the translucent n-type inorganic semiconductor layer 7 is inserted.
FIG. 3 is a diagram in which the electron donating organic material layer 4 in the device of FIG. 1 is replaced with a two-layer structure comprising a first electron donating organic material layer 41 and a second electron donating organic material layer 42.
FIG. 4 shows a transparent n-type inorganic semiconductor layer 7 inserted between the transparent electrode 2 and the electron-accepting organic material layer 3 in the element shown in FIG.

  The reason why the present device shown in FIGS. 1 to 4 has the photovoltaic ability (that is, also functions as a photosensor) is that the difference in Fermi level between the two layers at the interface between the electron-accepting organic material layer and the electron-donating organic material layer. This is due to the local internal electric field that occurs. Carriers are generated by absorbing light in the portion where the internal electric field works. This is finally taken out as an electric current. Therefore, how much light reaches and is absorbed at this interface, the ability to generate carriers such as the magnitude of the internal electric field generated between the electron-accepting organic layer and the electron-donating organic layer, the electron-accepting organic layer, and the electron donating The mobility and injectability of electrons and holes in the organic material layer are factors that greatly affect the conversion efficiency of the photovoltaic device. These are greatly affected by the materials used for the electron-accepting organic material layer and the electron-donating organic material layer. The present inventors have described the above-mentioned general formula (1) (the above general formula ( It was found that the photoelectric conversion efficiency is improved by including the polymer material represented by 2) to (4). Here, the conversion efficiency (η) of the photovoltaic element is expressed by the following equation.

(Equation 1)
η (%) = (Voc × Jsc × ff × 100) / Pin

  In the above equation, Voc is a voltage at the time of opening, Jsc is a current at the time of a short circuit, and ff is a value indicating a factor of a voltage-current curve at the time of light irradiation called a filter factor. Pin is the incident light energy.

The translucent n-type inorganic semiconductor layer 7 provided in FIG. 2 and FIG. 4 has a role of eliminating the energy barrier between the electron-accepting organic material layer and the electrode material and facilitating charge transfer, and the electron-accepting organic material layer. It is thought that it plays a role in eliminating the effects of pinholes.
The second electron-donating organic material layer 42 in FIGS. 3 and 4 is considered to play a role such as effective use of absorbed light in the photoactive layer and reduction of recombination probability of generated charges.

Next, various materials and manufacturing methods used for the photovoltaic device of the present invention will be described.
As the transparent insulating support 1 used in the present invention, glass, plastic film or the like is used.
As the transparent electrode 2 used in the present invention, indium tin oxide (ITO), tin oxide, indium oxide, zinc oxide, translucent Au, or the like is used. A preferable film thickness is 100 to 10,000 mm. As a material of the translucent n-type semiconductor layer 7 used in the present invention, zinc oxide, zinc oxide doped with a trivalent metal, CdS, titanium oxide, or the like is used. The film thickness is 10 to 10,000 mm.

  Examples of materials for the electron-accepting organic material layer 3 used in the present invention include perylene pigments (Pigment Red (hereinafter PR) 179, PR190, PR149, PR189, PR123, Pigment Brown 26, etc.), perinone pigments (Pigment Orange 43, PR). 194), anthraquinone pigments (PR168, PR177, Vat Yellow 4, etc.), quinone-containing yellow pigments such as flavanthrone, dye fluorenones such as crystal violet, methyl violet, malachite green, 2,4,7 trinitrofluorenone, tetra Examples include acceptor compounds such as cyanoquinodimethane and tetracyanoethylene. These are formed by vapor deposition, spin coating, or dipping. The film thickness is preferably 100 to 3000 mm.

  As the material of the first electron donating organic layer 41 used in the present invention, phthalocyanine pigments (divalent ones such as Cu, Zn, Co, Ni, Pb, Pt, Fe, Mg, etc., metal-free phthalocyanine, Oxygen such as aluminum chlorophthalocyanine, indium chlorophthalocyanine, indium bromophthalocyanine, trivalent metal phthalocyanine coordinated with halogen atoms such as gallium chlorophthalocyanine, chlorinated copper phthalocyanine, chlorinated zinc phthalocyanine, vanadyl phthalocyanine, titanyl phthalocyanine, etc. Phthalocyanine), indigo, thioindigo pigments (Pigment Blue 66, Pigment Violet 36, etc.), quinacridone pigments (Pigment Violet 19, Pigment Re) d 122, etc.), dyes such as merocyanine compounds, cyanine compounds, squalium compounds, and the like. These layers are formed by a known method such as vapor deposition, spin coating method, casting method, ink jet method, dipping coating method or the like. The thin film is preferably 50 to 3000 mm.

  Further, as the back electrode 5 used in the present invention, a metal having a high work function such as Au, Pt, Ni, Pd, Cu, Cr, or Ag is used. The film thickness is preferably 50 to 3000 mm.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in more detail, this invention is not limited at all by these Examples.

[Example 1]
On a well-cleaned ITO glass (manufactured by Matsuzaki Vacuum, 30Ω / □), perylenetetracarboxylic acid methylimide (PL-ME) was provided as an electron-accepting organic material layer in a thickness of about 400 mm by a vacuum deposition method. Next, a 1.0 wt% toluene solution of the following polymer (A) was prepared as the polymer compound represented by the general formula (1) used in the present invention. This solution was applied by spin coating to a film thickness of about 400 mm to form an electron donating organic material layer. Gold was vacuum deposited thereon. The area formed by ITO and gold was 0.25 cm ² . Lead wires were attached to the two electrodes with silver paste.

The conversion efficiency was measured by applying a voltage swept at 6 mV / s while irradiating white light of 75 mW / cm ² on the ITO side of this element. Voc = 0.38 V, Jsc = 1.85 mA / cm ² and ff = 0.38, and a conversion efficiency of 0.36% was obtained. This value is large for an organic photovoltaic device.

[Example 2]
On a well-cleaned ITO glass (manufactured by Matsuzaki Vacuum, 30Ω / □) at a substrate temperature of about 250 ° C., using argon as an introduction gas, and using a DC magnetron sputtering method, zinc oxide as a translucent n-type inorganic semiconductor layer is about 1500 mm. It was provided with the thickness. On top of that, perylenetetracarboxylic acid methylimide (PL-ME) was provided in a thickness of about 400 mm as an electron-accepting organic material layer by a vacuum deposition method. Next, a 1.0 wt% toluene solution of the following polymer (B) was prepared as the polymer compound represented by the general formula (1) used in the present invention. This solution was applied by spin coating to a film thickness of about 400 mm to form an electron donating organic material layer. Gold was vacuum deposited thereon. The area formed by ITO and gold was 0.25 cm ² . Lead wires were attached to the two electrodes with silver paste.

Thereafter, the conversion efficiency was measured in the same manner as in Example 1. As a result, Voc = 0.40V, Jsc = 1.85 mA / cm ² , and ff = 0.38, and a conversion efficiency of 0.37% was obtained. This value is large for an organic photovoltaic device.

[Example 3]
On a well-cleaned ITO glass (manufactured by Matsuzaki Vacuum, 30Ω / □), perylenetetracarboxylic acid methylimide (PL-ME) is deposited as an electron-accepting organic material layer by vacuum deposition at a thickness of about 400 mm, and then the first electron donation As the organic layer, aluminum chlorophthalocyanine (AlClPc) was provided with a thickness of about 100 mm. Furthermore, a 1.0 wt% toluene solution of the following polymer (C) was prepared as the polymer compound represented by the general formula (1) used in the present invention. This solution was applied by spin coating to a film thickness of about 400 mm to form a second electron donating organic material layer. Gold was vacuum deposited thereon. The area formed by ITO and gold was 0.25 cm ² . Lead wires were attached to the two electrodes with silver paste.

Thereafter, the conversion efficiency was measured in the same manner as in Example 1. As a result, Voc = 0.42V, Jsc = 1.9 mA / cm ² , ff = 0.42, and a conversion efficiency of 0.45% was obtained. This value is large for an organic photovoltaic device.

[Example 4]
On a well-cleaned ITO glass (manufactured by Matsuzaki Vacuum, 30Ω / □) at a substrate temperature of about 250 ° C., using argon as an introduction gas, and using a DC magnetron sputtering method, zinc oxide as a translucent n-type inorganic semiconductor layer is about 1500 mm. It was provided with the thickness. On the zinc oxide, perylenetetracarboxylic acid methylimide (PL-ME) is formed as an electron-accepting organic material layer in a thickness of about 400 mm by vacuum deposition, and then aluminum chlorophthalocyanine (AlClPc) is used as the first electron-donating organic material layer. It was provided with a thickness of 100 mm. Furthermore, a 1.0 wt% toluene solution of the polymer (A) was prepared as the polymer compound represented by the general formula (1) used in the present invention. This solution was applied by spin coating to a film thickness of about 400 mm to form a second electron donating organic material layer. Gold was vacuum deposited thereon.

Thereafter, the conversion efficiency was measured in the same manner as in Example 1. As a result, Voc = 0.43V, Jsc = 2.44 mA / cm ² , ff = 0.46, and a conversion efficiency of 0.64% was obtained. This value is large for an organic photovoltaic device.

[Example 5]
On a well-cleaned ITO glass (manufactured by Matsuzaki Vacuum, 30Ω / □) at a substrate temperature of about 250 ° C., using argon as an introduction gas, and using a DC magnetron sputtering method, zinc oxide as a translucent n-type inorganic semiconductor layer is about 1500 mm. It was provided with the thickness. On the zinc oxide, perylenetetracarboxylic acid methylimide (PL-ME) is formed as an electron-accepting organic material layer in a thickness of about 400 mm by vacuum deposition, and then aluminum chlorophthalocyanine (AlClPc) is used as the first electron-donating organic material layer. It was provided with a thickness of 100 mm. Furthermore, a 1.0 wt% toluene solution of the polymer (B) was prepared as the polymer compound represented by the general formula (1) used in the present invention. This solution was applied by spin coating to a film thickness of about 400 mm to form a second electron donating organic material layer. Gold was vacuum deposited thereon.
Thereafter, the conversion efficiency was measured in the same manner as in Example 1. As a result, Voc = 0.45V, Jsc = 2.23 mA / cm ² , ff = 0.46, and a conversion efficiency of 0.62% was obtained. This value is large for an organic photovoltaic device.

[Example 6]
On a well-cleaned ITO glass (manufactured by Matsuzaki Vacuum, 30Ω / □) at a substrate temperature of about 250 ° C., using argon as an introduction gas, and using a DC magnetron sputtering method, zinc oxide as a translucent n-type inorganic semiconductor layer is about 1500 mm. It was provided with the thickness. On the zinc oxide, perylenetetracarboxylic acid methylimide (PL-ME) is formed as an electron-accepting organic material layer in a thickness of about 400 mm by vacuum deposition, and then aluminum chlorophthalocyanine (AlClPc) is used as the first electron-donating organic material layer. It was provided with a thickness of 100 mm. Furthermore, a 1.0 wt% toluene solution of the polymer (C) was prepared as the polymer compound represented by the general formula (1) used in the present invention. This solution was applied by spin coating to a film thickness of about 400 mm to form a second electron donating organic material layer. Gold was vacuum deposited thereon.

Thereafter, the conversion efficiency was measured in the same manner as in Example 1. As a result, Voc = 0.45V, Jsc = 2.23 mA / cm ² , ff = 0.48, and a conversion efficiency of 0.64% was obtained. This value is large for an organic photovoltaic device.

It is typical sectional drawing which shows the specific example of the photovoltaic element which concerns on this invention. It is typical sectional drawing which shows another specific example of the photovoltaic element which concerns on this invention. It is typical sectional drawing which shows another specific example of the photovoltaic element which concerns on this invention. It is typical sectional drawing which shows another specific example of the photovoltaic element which concerns on this invention.

Explanation of symbols

1: transparent insulating support 2: transparent electrode 3: electron-accepting organic material layer 4: electron-donating organic material layer 5: back electrode 6: lead wire 7: translucent n-type inorganic semiconductor layer 41: first electron-donating organic material Layer 42: Second electron donating organic material layer

Claims (10)

In a photovoltaic device in which an electron-accepting organic material layer and an electron-donating organic material layer that generate an internal electric field by bonding are laminated between two electrodes, at least one of which is translucent,
A photovoltaic device, wherein the electron-donating organic layer contains at least a polymer material represented by the following general formula (1).

(Wherein R ¹ , R ² and R ³ each independently represents a halogen atom, a substituted or unsubstituted group, a group selected from a linear or branched alkyl group, an alkoxy group or an alkylthio group, and x, y , Z each independently represents an integer of 0 to 4, and when there are a plurality of R ¹ , R ² , R ³ , they may be the same or different, Ar is a substituted or unsubstituted aromatic hydrocarbon group Represents.) In the general formula (1), at least one of R ¹ , R ² , and R ³ is a substituted or unsubstituted group having 1 to 18 carbon atoms, and is a linear or branched alkyl group, an alkoxy group, or an alkylthio group. 2. The photovoltaic device according to claim 1, wherein The photovoltaic device according to claim 1, wherein the polymer material is represented by the following general formula (2).

(Wherein R ¹ , R ² , R ³ and R ⁴ each independently represents a halogen atom, a substituted or unsubstituted group selected from a linear or branched alkyl group, an alkoxy group or an alkylthio group; w represents an integer of 0 to 5, x, y, and z each independently represent an integer of 0 to 4, and when there are a plurality of R ¹ , R ² , R ³ , and R ⁴ , they may be the same or different. It may be different.) The photovoltaic element according to claim 1, wherein the polymer material is represented by the following general formula (3).

(Wherein R ¹ , R ² , R ³ , R ⁵ and R ⁶ are each independently a halogen atom, a substituted or unsubstituted group selected from a linear or branched alkyl group, an alkoxy group, or an alkylthio group. , U represents an integer from 0 to 5, v, x, y, and z each independently represent an integer from 0 to 4, and there are a plurality of R ¹ , R ² , R ³ , R ⁵ , and R ⁶ , respectively. They may be the same or different.) The photovoltaic device according to claim 1, wherein the polymer material is represented by the following general formula (4).

(In the formula, R ¹ , R ² , R ³ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are each independently a halogen atom, substituted or unsubstituted, a linear or branched alkyl group, an alkoxy group or an alkylthio group. Represents a group selected from the group, t represents an integer of 0 to 3, s, x, y, z each independently represents an integer of 0 to 4, R ¹ , R ² , R ³ , R ⁷ , When there are a plurality of R ^{8 s} , they may be the same or different.) In a photovoltaic device in which a transparent electrode, an electron-accepting organic material layer, an electron-donating organic material layer, and a back electrode are laminated in this order,
The photovoltaic material according to any one of claims 1 to 5, wherein the electron donating organic material layer contains a polymer material represented by any one of the general formulas (1) to (4). element. In a photovoltaic device in which a transparent electrode, a light-transmitting n-type inorganic semiconductor layer, an electron-accepting organic material layer, an electron-donating organic material layer, and a back electrode are laminated in this order,
The photovoltaic material according to any one of claims 1 to 5, wherein the electron donating organic material layer contains a polymer material represented by any one of the general formulas (1) to (4). element. In a photovoltaic device in which a transparent electrode, an electron-accepting organic material layer, a first electron-donating organic material layer, a second electron-donating organic material layer, and a back electrode are laminated in this order,
The light according to any one of claims 1 to 5, wherein the second electron-donating organic layer contains a polymer material represented by any one of the general formulas (1) to (4). Electromotive force element. In a photovoltaic device in which a transparent electrode, a light-transmitting n-type inorganic semiconductor layer, an electron-accepting organic material layer, a first electron-donating organic material layer, a second electron-donating organic material layer, and a back electrode are laminated in this order,
The light according to any one of claims 1 to 5, wherein the second electron-donating organic layer contains a polymer material represented by any one of the general formulas (1) to (4). Electromotive force element. An optical sensor comprising the photovoltaic element according to claim 1.

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