JP2009295395A - Photoelectric conversion element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photoelectric conversion element which needs no conductive substrate, achieves cost reduction, increases the efficiency of light reception, and has a new structure. <P>SOLUTION: In the photoelectric conversion element 1, a first electrode 10 and a second electrode 20 formed separately are arranged via an electrolyte 30. The first electrode 10 has a linear form, and is constituted of a first wire material 11 with the center metal 11A covered by a covering metal 11B, and a porous oxide semiconductor layer 12 which is arranged on the outer periphery of the first wire material 11 and carries dye. The second electrode 20 has a plate-like shape in which at least one part is covered by a nonconductive film 25, the first electrode 10 is arranged so as to go around the outside of the second electrode 20, and the electrolyte 30 is included in a space part of the porous semiconductor layer 12 or the nonconductive film 25. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a photoelectric conversion element used for a dye-sensitized solar cell or the like.

  The dye-sensitized solar cell has been proposed by a group such as Gretzel of Switzerland, and has attracted attention as a photoelectric conversion element that can be obtained at low cost and high conversion efficiency (for example, Patent Document 1 and Non-Patent Document 1). reference).

FIG. 5 is a cross-sectional view showing an example of a conventional dye-sensitized solar cell.
The dye-sensitized solar cell 100 includes a first substrate 101 having a porous semiconductor electrode 103 (hereinafter also referred to as a dye-sensitized semiconductor electrode) 103 carrying a sensitizing dye formed on one surface, and a conductive film 104. And the electrolyte layer 106 including a redox pair such as iodine / iodide ions enclosed between them is a main component.

A light-transmitting plate material is used as the first substrate 101, and a transparent conductive layer 102 is disposed on the surface of the first substrate 101 in contact with the dye-sensitized semiconductor electrode 103 in order to provide conductivity. A working electrode (window electrode) 108 is formed by the substrate 101, the transparent conductive layer 102, and the dye-sensitized semiconductor electrode 103.
On the other hand, as the second substrate 105, a conductive layer 104 made of, for example, carbon or platinum is provided on the surface on the side in contact with the electrolyte layer 106, and the counter electrode 109 is formed by the second substrate 105 and the conductive layer 104. Is configured.

  The first substrate 101 and the second substrate 105 are arranged at a predetermined interval so that the dye-sensitized semiconductor electrode 103 and the conductive layer 104 face each other, and a peripheral portion between the two substrates is sealed with, for example, a thermoplastic resin Agent 107 is provided. Then, the two substrates 101 and 105 are bonded together through the sealant 107 to assemble a cell, and an oxidation / reduction pair such as iodine / iodide ions is included between the electrodes 108 and 109 through the electrolyte injection port 110. Examples thereof include an organic electrolyte solution filled and an electrolyte layer 106 for charge transfer formed.

  In such a dye-sensitized photoelectric conversion element, since the electrode (window electrode) on which light is incident is particularly required to have a visible light transmission property and high conductivity, it can be formed on a glass substrate or a plastic substrate. Substrates coated with transparent conductive metal oxides such as tin-doped indium oxide (ITO) and fluorine-doped tin oxide (FTO) have been used.

However, indium (In) or the like used for the conductive substrate of the dye-sensitized photoelectric conversion element described above is a rare metal and hinders the cost reduction of the photoelectric conversion element from the recent increase in price. It is a factor. Therefore, if a dye-sensitized photoelectric conversion element that does not require a conductive substrate and has a structure that can suppress the use of rare metals can be realized, the cost can be greatly reduced, and its development is expected. It was. However, in that case, it is necessary to satisfy simultaneously that the light receiving efficiency is not sacrificed.
Japanese Patent Laid-Open No. 1-220380 M. Graetzel et al., Nature, 737, p.353, 1991

The present invention has been made in view of the above circumstances, and provides a photoelectric conversion element having a new structure that eliminates the need for a conductive substrate, can reduce costs, and can have excellent light receiving efficiency. This is the primary purpose.
In addition, the present invention provides a photoelectric conversion element that can easily and in large quantities stably manufacture a photoelectric conversion element having a new structure that is lightweight and excellent in corrosion resistance while reducing the cost by eliminating the need for a conductive substrate. The second object is to provide a method.

  The photoelectric conversion element according to claim 1 of the present invention is a photoelectric conversion element in which a first electrode and a second electrode which are separate bodies are arranged via an electrolyte, and the first electrode includes a wire A first wire comprising a central metal coated with a coating metal, and a porous oxide semiconductor layer disposed on the outer periphery of the first wire and carrying a dye, The second electrode has a plate shape at least partially covered with a non-conductive film, the first electrode is arranged so as to go around the outside of the second electrode, and the electrolyte is the porous It is contained in the space part of the quality semiconductor layer or the said nonelectroconductive film | membrane.

  The photoelectric conversion element according to claim 2 of the present invention is characterized in that the first electrode, the second electrode, and the non-conductive film are arranged in an electrolyte.

  In the photoelectric conversion element according to claim 3 of the present invention, the central metal is any one selected from aluminum, aluminum alloy, magnesium, magnesium alloy, copper, carbon fiber, carbon-coated titanium wire, and titanium composite wire. It consists of the metal material of.

  The photoelectric conversion element according to claim 4 of the present invention is characterized in that the shape of the first electrode is a flat wire or a polygonal wire.

The photoelectric conversion element according to the present invention uses a first electrode composed of a conductive first wire and a porous oxide semiconductor layer that is disposed on the outer periphery of the first wire and carries a dye. Thus, a conductive substrate is not required, and a new structure that can reduce costs is obtained.
In particular, as a configuration of the first wire rod, a metal having a low specific gravity and high conductivity, or an alloy of such a metal is used, and the outer periphery thereof is coated with titanium or the like, so that the first wire rod does not have only titanium. While reducing the weight of the wire, the conductivity of the conductive wire can be increased and the cost can be reduced.
Moreover, since the photoelectric conversion element according to the present invention is arranged so that the first electrode circulates around the outer periphery of the plate-like second electrode, it can receive light without waste and can improve the light receiving efficiency.
Further, according to the photoelectric conversion element according to the present invention, a housing for holding the electrolyte is not necessary, and thus the photoelectric conversion element can be manufactured easily and at low cost.

<First embodiment>
FIG. 1A shows a part of a cross-sectional view of the photoelectric conversion element 1A (1) shown as the first embodiment of the present invention taken along AA ′ in FIG. FIG. 1B is a perspective view of the photoelectric conversion element 1A (1).
In FIG. 1A, 1A (1) is a dye-sensitized photoelectric conversion element, 10 is a first electrode (working electrode), 20 is a second electrode (counter electrode), 11 is a first wire, and 12 is porous. The oxide semiconductor layer 30 indicates an electrolyte.
The first electrode 10 of the present invention is composed of a first wire 11 having at least conductivity, and a porous oxide semiconductor layer 12 disposed on the outer periphery of the first wire 11 and carrying a sensitizing dye, It is characterized by being linear.

The first wire 11 is composed of a central metal 11A and a covering metal 11B that covers the central metal 11A.
As the central metal 11A, it is conceivable to use a single metal of Ti, Ni, W, Rh, or Mo, or a wire made of an alloy thereof, a hollow wire, a bar, or the like. In order to improve the corrosion resistance, workability, weight reduction, electrical conductivity, etc., a single metal such as aluminum (Al), magnesium (Mg), silver (Ag), etc., or a linear shape made of these alloys A substrate can be used. In this case, in order to maintain the uniformity of the surface of the central metal, to prevent oxidation, to increase the degree of fusion, etc., a material coated with a metal such as titanium made of an electrochemically inert material with respect to the electrolyte 30 is used. It is desirable to use it.
Ti, Ni, W, Rh, and Mo can be used as the covering metal 11B.
In order to enhance the fusion of the center metal 11A and the covering metal 11B of the first wire 11, a composite wire of a copper (Cu) -coated Al wire or a Cu-coated Al alloy wire is used as the center metal 11A. It is also possible to cover the first wire 11 with a multiple structure by coating with Ti.
Furthermore, the central metal can be a Pt wire, a Ti wire coated with Pt or a Ti composite wire, or a carbon fiber, a Ti wire coated with carbon, and a Ti composite wire.
The carbon fiber in the present invention is composed of a single-walled carbon nanotube or a multi-walled carbon nanotube. Moreover, it is so preferable that a specific surface area is large.
The carbon-coated titanium wire in the present invention is coated with porous carbon. Moreover, it is so preferable that a specific surface area is large.

  The thickness (diameter) of the first wire 11 is not particularly limited, but is preferably 10 [μm] to 10 [mm], for example. However, in order to fully exhibit flexibility, the thickness of the first wire 11 is better as it is thinner.

The porous oxide semiconductor layer 12 is provided around the first wire 11, and a sensitizing dye and an electrolyte 30 are supported on at least a part of the surface of the porous oxide semiconductor layer 12.
The porous oxide semiconductor layer 12 may cover only a part of the outer periphery of the first wire 11. However, the porous oxide semiconductor layer 12 has a decrease in the light collection capability, the promotion of the reverse electron transfer reaction, etc. It is preferable to completely cover the outer periphery of the wire 11.

The semiconductor for forming the porous oxide semiconductor layer 12 is not particularly limited, and any semiconductor can be used as long as it is generally used for forming a porous oxide semiconductor for a photoelectric conversion element. As such a semiconductor, for example, titanium oxide (TiO ₂ ), tin oxide (SnO ₂ ), zinc oxide (ZnO), niobium oxide (Nb ₂ O ₅ ), tungsten oxide (WO ₃ ), or the like can be used. .

As a method for forming the porous oxide semiconductor layer 12, for example, a dispersion in which commercially available oxide semiconductor fine particles are dispersed in a desired dispersion medium or a colloidal solution that can be prepared by a sol-gel method is used as necessary. Then, after adding a desired additive, it is arranged on the outer periphery of the first wire 11 by a method such as dipping, coating, or extruding, followed by firing.
The thickness of the porous oxide semiconductor layer 12 is not particularly limited, but is preferably 1 [μm] to 50 [μm], for example.

  As the sensitizing dye, ruthenium complexes such as N3 and black dye, metal-containing complexes such as porphyrin and phthalocyanine, and organic dyes such as eosin, rhodamine and merocyanine can be applied. What has taken the excitation behavior suitable for a semiconductor should just be selected suitably.

  An example of a manufacturing method of the first wire 11 will be described, for example, when the coated metal 11B is Ti and the central metal 11A is Al. First, Ti is formed into a pipe shape by extrusion molding, and Al is extrusion molded. In this way, the Ti pipe and the aluminum wire are run simultaneously, and the Al wire is inserted into the Ti pipe while the Ti pipe and the aluminum wire are running at the same time. Thereafter, these are baked to oxidize the outside of the Ti coating layer to form a porous semiconductor layer, and to carry the sensitizing dye.

The second electrode 20 has a conductive plate shape, and is composed of various metal substrates, particularly titanium plates, whose surfaces are non-conductive. The second electrode 20 has a catalyst film (not shown) made of Pt, C, polyethylenedioxythiophene (PEDOT) or the like on the surface. At that time, the coating is preferably made of a metal such as Pt. Further, at least a part of the counter electrode 20 is covered with a mesh-like non-conductive film 25 using nylon fibers so as not to be short-circuited by contact with the first electrode 10. The electrolyte solution is supported in the mesh space that constitutes the membrane 25, and the membrane 25 constitutes a layer of the electrolyte 30 (electrolyte layer).
The thickness of the second electrode 20 is preferably about 0.1 mm, and the thickness of the membrane 25 is preferably 16 μm.

When the second electrode 20 is rod-shaped, if the first electrode is wound around the rod-shaped second electrode, the entire first electrode is subjected to bending strain. Thus, if it receives distortion, the characteristic of a photoelectric conversion element may fall. Therefore, in the case of the rod-like second electrode, it is necessary to increase the diameter of the second electrode in order to reduce the deterioration of the characteristics.
On the other hand, in the photoelectric conversion element of the present invention, the second electrode 20 has a plate shape. For this reason, when the first electrode 10 is wound, the turn portion of the first electrode 10 is distorted, but the other portions are not distorted, so that the photoelectric conversion element can be downsized. Can do.

  Examples of the conductive polymer constituting the material of the second electrode 20 include PEDOT [Poly (3,4-ethylenedioxythiophene): “polyethylenedioxythiophene]] derivatives, PANI [Polyaniline] derivatives, and the like. .

  The porous oxide semiconductor layer 12 is impregnated with an electrolytic solution, and this electrolytic solution also constitutes a part of the electrolyte 30. In this case, the electrolyte 30 in the porous oxide semiconductor layer 12 is formed by impregnating the porous oxide semiconductor layer 12 with the electrolytic solution, or impregnating the porous oxide semiconductor layer 12 with the electrolytic solution. Then, the electrolytic solution is gelled (pseudo-solidified) using an appropriate gelling agent and formed integrally with the porous oxide semiconductor layer 12, or based on an ionic liquid. Further, a gel electrolyte containing oxide semiconductor particles and conductive particles is used.

  The nonconductive film 25 has a net shape using, for example, a nonconductive nylon fiber, covers at least a part of the second electrode 20, and forms a separator between the first electrode 10 and the second electrode 20. Play a role. Furthermore, the nonconductive film 25 plays a role of holding the electrolyte 30 between the first electrode 10 and the second electrode 20 in the network of the nonconductive film 25. The non-conductive film 25 is preferably 1 to 100 μm in thickness. As the non-conductive film 25, a mesh using polyethylene fibers or a mesh using ceramic can be used, but it can withstand the electrolyte and insulate the first electrode 10 and the second electrode 20 from each other. If there is, it is not limited to these.

As said electrolyte solution, what melt | dissolved electrolyte components, such as an iodine, iodide ion, and tertiary butyl pyridine, in organic solvents and ionic liquids, such as ethylene carbonate and methoxyacetonitrile, is used.
Examples of the gelling agent used for gelling the electrolytic solution include polyvinylidene fluoride, a polyethylene oxide derivative, and an amino acid derivative.
Moreover, if it replaces with a volatile electrolyte solution and is generally used for a dye-sensitized solar cell, not only what a solvent is an ionic liquid or the gelatinized thing but a p-type inorganic semiconductor and an organic hole transport layer Even solids such as these can be used without limitation.

Although it does not specifically limit as said ionic liquid, It is a liquid at room temperature, For example, the normal temperature molten salt which used the compound which has the quaternized nitrogen atom as a cation is mentioned.
Examples of the cation of the room temperature molten salt include quaternized imidazolium derivatives, quaternized pyridinium derivatives, and quaternized ammonium derivatives.
Examples of the anion of the ambient temperature molten _{^{salt, BF 4 -, PF 6 -}} , (HF) n -, bis (trifluoromethylsulfonyl) imide _{[N (CF 3 S0 2)} 2 -], and the like iodide ion.
Specific examples of the ionic liquid include salts composed of quaternized imidazolium-based cations and iodide ions or bistrifluoromethylsulfonylimide ions.

  The oxide semiconductor particles are not particularly limited in terms of the type and particle size of the substance, but those that are excellent in miscibility with an electrolytic solution mainly composed of an ionic liquid and that gel the electrolytic solution are used. Further, the oxide semiconductor particles are required to have excellent chemical stability against other coexisting components contained in the electrolyte 30 without reducing the semiconductivity of the electrolyte 30. In particular, even when the electrolyte 30 includes a redox pair such as iodine / iodide ions or bromine / bromide ions, the oxide semiconductor particles are preferably those that do not deteriorate due to an oxidation reaction.

Examples of such oxide semiconductor particles include TiO ₂ , SnO ₂ , SiO ₂ , ZnO, Nb ₂ O ₅ , In ₂ O ₃ , ZrO ₂ , Al ₂ O ₃ , WO ₃ , SrTiO ₃ , Ta ₂ O ₅ , One or a mixture of two or more selected from the group consisting of La ₂ O ₃ , Y ₂ O ₃ , Ho ₂ O ₃ , Bi ₂ O ₃ , CeO ₂ is preferable, and the average particle size is about 2 nm to 1000 nm. preferable.

As the conductive fine particles, conductive particles such as a conductor and a semiconductor are used.
Further, the type and particle size of the conductive particles are not particularly limited, and those that are excellent in miscibility with an electrolytic solution mainly composed of an ionic liquid and that gel this electrolytic solution are used. Furthermore, it is necessary to be excellent in chemical stability against other coexisting components contained in the electrolyte 30. In particular, even when the electrolyte 30 includes a redox pair such as iodine / iodide ions or bromine / bromide ions, it is preferable that the electrolyte 30 does not deteriorate due to an oxidation reaction.

  Examples of such conductive fine particles include those composed mainly of carbon, and specific examples include particles such as carbon nanotubes, carbon fibers, and carbon black. All methods for producing these substances are known, and commercially available products can also be used.

The entire photoelectric conversion element 1A (1) according to the present invention will be described.
As shown in FIG. 1A, the photoelectric conversion element 1 </ b> A (1) of the present invention includes a separate first electrode (working electrode) 10 and second electrode (counter electrode) 20 via an electrolyte 30. The first electrode 10 includes a first wire 11 in which a central metal 11A is coated with a covering metal 11B made of a material that is electrochemically inactive with respect to the electrolyte 30; It is arranged on the outer periphery of the wire 11 and has a linear shape composed of a porous oxide semiconductor layer 12 carrying a dye. The porous oxide semiconductor layer 12 of the first electrode 10 is impregnated with an electrolyte together with a sensitizing dye. The second electrode 20 has a non-conductive net (mesh) non-conductive film 25 on at least a part of its surface, and holds the electrolyte solution that constitutes the electrolyte 30 in the mesh space of the film 25. is doing. The first electrode 10 has a structure in contact with the outer periphery of the second electrode 20 through the membrane 25 and the electrolyte 30 serving as a separator by being wound as shown in FIG.
The first electrode 10 has an appropriate terminal with a length such that the electrical resistance of the wire 11 is 0.1Ω or less, and the entire photoelectric conversion element 1 has a plurality of wires 11 (coils) wound around the second electrode 20. It is desirable to do so.
Further, it is desirable that the width of the first electrode 10 wound around the second electrode 20 is as dense as possible so that the light receiving efficiency can be improved.

Next, the manufacturing method of photoelectric conversion element 1A (1) of 1st embodiment is demonstrated.
As shown in FIG. 2A, the first electrode 10 is wound around the second electrode 20. At this time, as described above, the end of the first wire 11 is taken with an appropriate length so that the electrical resistance of the first wire 11 does not become too large, and the plurality of first wires 11 (coils) are the second electrodes. Wrap around 20 Next, as shown in FIG. 2B, the block in which the first electrode 10 is wound around the second electrode 20 is immersed in a volatile electrolytic solution using, for example, methoxyacetonitrile as a solvent, and the first electrode 10 and the first electrode 10 A block in which the first electrode 10 is wound around the second electrode 20 as shown in FIG. 2C after the electrolyte 30 is sufficiently filled in the mesh of the film 25 covering at least a part of the two electrodes 20. Is lifted from the solvent of the volatile electrolyte to complete the solar cell.

<Second embodiment>
Hereinafter, 2nd embodiment of the photoelectric conversion element 1 which concerns on this invention is described based on FIG.
FIG. 3 is a diagram illustrating another example of the photoelectric conversion element 1 according to this embodiment. FIG. 3A is a cross-sectional view of the photoelectric conversion element 1B (1) shown as the second embodiment of the present invention, cut along BB ′ in FIG. b) is a perspective view of the photoelectric conversion element 1B (1). In the present embodiment, differences from the first embodiment described above will be mainly described, and description of similar parts will be omitted.

  In the photoelectric conversion element 1B (1) of the second embodiment, a block in which the first electrode 10 having the same configuration as that of the first embodiment is wound around the second electrode 20 is made of transparent substrates 40 (a), 40 ( b) and a sealing member 50, and is characterized by being arranged in a casing in which a solvent of an electrolytic solution is held.

  As the transparent base material 40a, 40b, a substrate made of a light-transmitting material is used, and a non-alkali glass substrate, other glass substrate, a resin substrate, for example, glass, polyethylene terephthalate, polycarbonate, polyethersulfone, etc. Any material can be used as long as it can be used as a transparent substrate of a photoelectric conversion element. The transparent base materials 40a and 40b are appropriately selected from these in consideration of resistance to the electrolytic solution. Moreover, as a transparent base material 40a, 40b, the board | substrate which is excellent in the light transmittance as much as possible is preferable on a use, and the board | substrate whose transmittance | permeability is 85% or more is more preferable.

  The sealing member (spacer) 50 is not particularly limited as long as it has excellent adhesion to the transparent substrates 40a and 40b. For example, an adhesive made of a thermoplastic resin having a carboxylic acid group in the molecular chain is used. Desirably, specifically, in addition to High Milan (Mitsui DuPont Polychemical Co., Ltd.) and Binnel (DuPont Co., Ltd.), UV curable materials [e.g.

  As shown in FIGS. 4A to 4C, the shape of the first electrode 10 and the second electrode (not shown) can be a deformed line such as a flat line or a polygonal line more than a triangle.

According to the photoelectric conversion element 1 according to the present invention, a first wire 11 having conductivity and a porous oxide semiconductor layer 12 that is arranged on the outer periphery of the first wire 11 and carries a dye, is provided. By using the electrode 10, since a glass substrate and a transparent conductive film are not used unlike the conventional electrode, an electrode can be manufactured at low cost.
In particular, according to the photoelectric conversion element 1 according to the present invention, the center line of the first wire 11 is made of a metal having high corrosion resistance, high conductivity, low cost, and light weight, and Ti or the like is used for the center line. By using the metal composite wire coated with, the electrical conductivity can be kept high while enhancing the corrosion resistance, and the weight can be reduced.
In addition, according to the photoelectric conversion element 1 according to the present invention, a housing for holding the electrolyte 30 is not necessarily required, and thus the photoelectric conversion element can be manufactured easily and at low cost.
Moreover, according to the photoelectric conversion element 1 based on this invention, since the outer peripheral surface of the linear 1st electrode 10 turns into a light-receiving surface, the projection area with respect to irradiated light can be increased, and light incident angle dependence is increased. Expected to decrease.
Moreover, according to the photoelectric conversion element 1 according to the present invention, since the first electrode 10 is arranged around the outer periphery of the plate-like second electrode 20, the first electrode 10 may be blocked by other members. Therefore, light can be received without waste, and the light receiving efficiency can be improved.
In addition, according to the photoelectric conversion element 1 according to the present invention, the photoelectric conversion element 1 is disposed in a casing holding an electrolytic solution and sealed, thereby preventing evaporation of the electrolytic solution and stably for a long period of time. Solar cells can be used.
Moreover, according to the photoelectric conversion element 1 based on this invention, it becomes possible to raise the fusion degree of 11 A of center wires of the 1st wire 11, and the covering metal 11B by making the 1st wire 11 into a multiple structure.
Moreover, according to the photoelectric conversion element 1 based on this invention, the terminal process at the time of current collection becomes easy by making the 1st wire 11 and / or the 2nd electrode 20 into a rectangular or polygonal shape. In addition, when winding a plurality of times, the filling rate can be improved.

It is sectional drawing and a perspective view which show an example of the photoelectric conversion element which concerns on this invention. It is a perspective view which shows the preparation methods of the photoelectric conversion element which concerns on this invention. It is sectional drawing and a perspective view which show another example of the photoelectric conversion element which concerns on this invention. It is a perspective sectional view showing the example of the shape of the 1st electrode concerning the present invention. It is sectional drawing which shows the example of the conventional photoelectric conversion element.

Explanation of symbols

  1 (1A, 1B): photoelectric conversion element, 10: first electrode, 11: first wire, 11A: central metal, 11B: coating metal, 12: porous oxide semiconductor layer, 20: second electrode, 25: Non-conductive film, 30: electrolyte, 40 (40a, 40b): transparent substrate, 50: sealing member.

Claims (4)

A photoelectric conversion element in which a first electrode and a second electrode forming separate bodies are arranged via an electrolyte,
The first electrode has a linear shape, and includes a first wire having a central metal coated with a coating metal, a porous oxide semiconductor layer disposed on the outer periphery of the first wire, and carrying a dye. Consists of
The second electrode has a plate shape at least partially covered with a non-conductive film,
The first electrode is arranged so as to go around the outside of the second electrode,
The photoelectric conversion element, wherein the electrolyte is contained in a space of the porous semiconductor layer or the non-conductive film.   The photoelectric conversion element according to claim 1, wherein the first electrode, the second electrode, and the non-conductive film are arranged in an electrolyte.   The center metal is made of any one metal material selected from aluminum, aluminum alloy, magnesium, magnesium alloy, copper, carbon fiber, carbon-coated titanium wire, and titanium composite wire. 2. The photoelectric conversion element according to 2.   The photoelectric conversion element according to claim 1, wherein the shape of the first electrode is a rectangular wire or a polygonal wire.

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