JP2019195019A - Photoelectric conversion element - Google Patents

Abstract

To provide a photoelectric conversion element that is able to improve durability.SOLUTION: A photoelectric conversion element 100 comprises a first substrate; a conductive part 12 provided on one surface of the first substrate; and a peripheral part 60 provided on the one surface of the first substrate and along the periphery of the conductive part, the conductive part having an electrode 12A. The photoelectric conversion element has a photoelectric conversion cell 50. The photoelectric conversion cell has: an electrode; a second substrate 21; and a sealing part 30 joining the first substrate and the second substrate. The conductive part and the peripheral part are arranged via the insulation groove 90. When the photoelectric conversion element is viewed in a direction orthogonal to the one surface of the first substrate, at least part of the sealing part is disposed so as to overlap the insulation groove. The peripheral part is divided into a plurality of separate peripheral parts by at least one separate groove 91 communicating with the insulation groove and extending from the insulation groove and to an outer peripheral edge 60a of the peripheral part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a photoelectric conversion element.

  As a photoelectric conversion element, a photoelectric conversion element using a dye has attracted attention because it is inexpensive and can provide high photoelectric conversion efficiency.

  As a photoelectric conversion element using such a dye, a dye-sensitized solar cell element described in Patent Document 1 below is known. This dye-sensitized solar cell element includes a substrate and at least one photoelectric conversion cell, and the photoelectric conversion cell is opposed to the first transparent conductive layer provided on the substrate and the first transparent conductive layer. The substrate includes a sealing portion that joins the first transparent conductive layer and the counter substrate. A second transparent conductive layer is provided on the substrate and outside the first transparent conductive layer, and a groove is formed between the second transparent conductive layer and the first transparent conductive layer. .

JP 2014-211951 A (FIG. 10)

  However, the dye-sensitized solar cell element described in Patent Document 1 has the following problems.

  That is, the dye-sensitized solar cell element described in Patent Document 1 has room for improvement in terms of improvement in durability.

  This invention is made | formed in view of the said situation, and it aims at providing the photoelectric conversion element which can improve durability.

  In order to solve the above problems, the present invention provides a first substrate, a conductive portion provided on one surface of the first substrate, and a peripheral portion provided along the periphery of the conductive portion on one surface of the first substrate. A photoelectric conversion element having an electrode in which the conductive portion has an electrode, the photoelectric conversion cell having the electrode, a second substrate facing the electrode, and the first substrate. And a sealing portion for joining the second substrate, the conductive portion and the peripheral portion are arranged via an insulating groove, and the photoelectric conversion element is arranged in a direction perpendicular to the one surface of the first substrate. When viewed, at least a part of the sealing portion is disposed so as to overlap the insulating groove, and the peripheral portion communicates with the insulating groove and extends from the insulating groove to the outer peripheral edge of the peripheral portion. A photoelectric device that is divided into a plurality of divided peripheral portions by dividing grooves. Is 換素Ko.

  According to this photoelectric conversion element, a fine crack may be formed along the insulating groove in the first substrate. In this case, even if moisture in the air accumulates through the crack in the insulating groove, the moisture is pushed out from the insulating groove to the outer peripheral edge of the peripheral portion through the dividing groove and discharged. That is, the dividing groove serves as a moisture escape route. For this reason, it is sufficiently suppressed that moisture enters the inside of the photoelectric conversion cell from the insulating groove through the sealing portion. As a result, the photoelectric conversion element of the present invention can improve durability as compared with the case where the peripheral portion is not divided into a plurality of divided peripheral portions by at least one dividing groove.

  In the said photoelectric conversion element, it is preferable that the said dividing groove is formed in the said peripheral part on the outer side of the outer periphery of the said sealing part of the said photoelectric conversion cell.

  In this case, outside the sealing portion of the photoelectric conversion cell, moisture accumulated in the insulating groove is pushed out to the outer peripheral edge of the peripheral portion through the dividing groove. That is, the amount of moisture is reduced before the moisture enters the inside of the outer peripheral edge of the sealing portion. For this reason, a photoelectric conversion element can fully improve durability compared with the case where the parting groove | channel is not formed in the peripheral part outside the outer periphery of the sealing part of a photoelectric conversion cell.

  In the photoelectric conversion element, it is preferable that the insulating groove has at least one intersecting portion intersecting the dividing groove, and the intersecting portion includes a dividing groove intersecting portion where a plurality of the dividing grooves intersect with each other. .

  In this case, since the plurality of dividing grooves intersect at the dividing groove intersecting portion of the insulating groove intersecting portion, moisture is not discharged from only one dividing groove at the dividing groove intersecting portion of the insulating groove, but a plurality of dividing grooves. Discharged from. For this reason, the discharge of moisture from the insulating groove can be more sufficiently promoted at the dividing groove intersecting portion of the insulating groove.

  The photoelectric conversion element further includes an insulating material provided on one surface of the first substrate, wherein the at least one dividing groove includes a first dividing groove into which the insulating material is entirely inserted, and the insulating material is entirely formed. It is preferable to be configured by a second dividing groove that does not enter.

  In this case, it is possible to promote the discharge of moisture from the insulating groove by the second dividing groove while sufficiently suppressing the intrusion of moisture into the first dividing groove that is entirely covered with the insulating material.

  ADVANTAGE OF THE INVENTION According to this invention, the photoelectric conversion element which can improve durability is provided.

It is a top view which shows 1st Embodiment of the photoelectric conversion element of this invention. It is sectional drawing along the II-II line of FIG. It is a top view which shows the pattern of the electroconductive part and peripheral part in the photoelectric conversion element of FIG. 6 is a plan view showing a photoelectric conversion element of Example 2. FIG. 6 is a plan view showing a photoelectric conversion element of Example 3. FIG. 6 is a plan view showing a photoelectric conversion element of Example 4. FIG. 6 is a plan view showing a photoelectric conversion element of Example 5. FIG. 6 is a plan view showing a photoelectric conversion element of Comparative Example 1. FIG.

  Hereinafter, a preferred embodiment of the photoelectric conversion element of the present invention will be described in detail with reference to FIGS. 1 is a plan view showing a first embodiment of the photoelectric conversion element of the present invention, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and FIG. 3 is a conductive portion in the photoelectric conversion element in FIG. It is a top view which shows the pattern of a peripheral part.

  As shown in FIGS. 1 to 3, the photoelectric conversion element 100 is conductive on the transparent substrate 11 as the first substrate, the conductive portion 12 provided on the one surface 11 a of the transparent substrate 11, and the one surface 11 a of the transparent substrate 11. A conductive substrate 15 having a peripheral portion 60 provided along the periphery of the portion 12 is provided. The conductive portion 12 is integrated with the electrode 12A, the first current extraction portion 12B disposed away from the electrode 12A, and the electrode 12A, and is disposed second away from the first current extraction portion 12B. A current extraction unit 12C. In addition, as shown in FIG. 3, the electroconductive part 12 is an area | region enclosed with the dashed-two dotted line.

  The conductive portion 12 and the peripheral portion 60 are disposed via the insulating groove 90. In the conductive portion 12, the first current extraction portion 12B, the electrode 12A, and the second current extraction portion 12C are disposed via the internal insulating groove 90A.

  The peripheral portion 60 communicates with the insulating groove 90 and is divided into a plurality of divided peripheral portions by a plurality of dividing grooves 91 (hereinafter referred to as dividing grooves 91a to 91g as necessary) extending from the insulating groove 90 to the outer peripheral edge 60a of the peripheral portion 60. It is divided into 60A-60H. The insulating groove 90 has a plurality of intersecting portions 92 that intersect with the dividing grooves 91, and the intersecting portions 92 are composed of intersecting portions 92a, 92b, 92d, 92e, and 92g. Among these intersecting portions 92, the intersecting portions 92b and 92e are divided groove intersecting portions where a plurality of dividing grooves intersect with each other, and a plurality of dividing grooves 91b and 91c intersect at the dividing groove intersecting portion 92b. The dividing grooves 91e and 91f intersect at the dividing groove intersecting portion 92e. On the other hand, the remaining dividing grooves 91a, 91d, and 91g each independently intersect the intersecting portions 92a, 92d, and 92g. Here, the dividing grooves 91a, 91b, 91f, and 91g are shorter than the dividing grooves 91c, 91d, and 91e. Moreover, all of the dividing grooves 91a to 91g are formed in the peripheral portion 60 outside the outer peripheral edge 30a of the sealing portion 30 (see FIG. 1).

  The photoelectric conversion element 100 includes one photoelectric conversion cell (hereinafter simply referred to as “cell”) 50.

  The cell 50 includes an electrode 12A, an oxide semiconductor layer 13 provided on the electrode 12A, a counter electrode 20 as a second substrate facing the electrode 12A, a sealing portion 30 that joins the transparent substrate 11 and the counter electrode 20, and An electrolyte 40 surrounded by the sealing part 30 between the electrode 12A and the counter electrode 20 and an insulating material 33 made of an insulating material provided on the one surface 11a side of the transparent substrate 11 are provided.

  The oxide semiconductor layer 13 is disposed inside the sealing portion 30. The oxide semiconductor layer 13 carries a dye.

  A part of the sealing portion 30 is disposed so as to overlap with the insulating groove 90 when the photoelectric conversion element 100 is viewed in a direction orthogonal to the one surface 11 a of the transparent substrate 11.

  The counter electrode 20 includes a metal substrate 21 and a catalyst layer 22 that is provided on the electrode 12 </ b> A side of the metal substrate 21 and contributes to the reduction of the electrolyte 40.

  When the insulating material 33 is viewed in a direction orthogonal to the one surface 11a of the transparent substrate 11 and the inner insulating material 33a provided along the sealing portion 30 between the sealing portion 30 and the electrode 12A. And an outer insulating material 33b extending from the sealing portion 30 in opposite directions to each other.

  The outer insulating material 33b enters the entire insulating groove 90 and the inner insulating groove 90A on the outer side of the sealing portion 30, and the outer insulating material 33b is included in the dividing grooves 91c, 91d, and 91e (first dividing grooves). It ’s all in. Further, in each of the dividing grooves 91a, 91b, 91f, and 91g (second dividing grooves), the outer insulating material 33b partially enters. Note that the outer insulating material 33b does not necessarily show through the configuration of the conductive substrate 15 below, but in FIG. 1, in order to facilitate understanding of the positional relationship between the outer insulating material 33b and the dividing groove 91. The dividing groove 91 is shown so as to be seen through.

  A first external connection terminal 18a for taking out current from the cell 50 is provided on the first current extraction portion 12B, and a first external connection terminal 18a for taking out current from the cell 50 is provided on the second current extraction portion 12C. 2 An external connection terminal 18b is provided (see FIG. 1).

  According to the photoelectric conversion element 100, a fine crack may be formed along the insulating groove 90 in the transparent substrate 11. In this case, even if moisture in the air accumulates through the crack in the insulating groove 90, the moisture is pushed out from the insulating groove 90 to the outer peripheral edge 60 a of the peripheral portion 60 through the dividing groove 91 and discharged. That is, the dividing groove 91 becomes a moisture escape path. For this reason, it is sufficiently suppressed that moisture enters the cell 50 from the insulating groove 90 through the sealing portion 30. As a result, the photoelectric conversion element 100 can improve durability as compared with the case where the peripheral portion 60 is not divided into the plurality of divided peripheral portions 60A to 60H by the plurality of dividing grooves 91.

  In the photoelectric conversion element 100, the dividing grooves 91 a to 91 g are all formed in the peripheral portion 60 outside the outer peripheral edge 30 a of the sealing portion 30. In this case, outside the outer peripheral edge 30 a of the sealing portion 30 of the cell 50, moisture accumulated in the insulating groove 90 is pushed out to the outer peripheral edge 60 a of the peripheral portion 60 through the dividing groove 91. That is, the amount of moisture is reduced before the moisture enters the inside of the outer peripheral edge 30 a of the sealing portion 30. Therefore, the photoelectric conversion element 100 can sufficiently improve the durability compared to the case where the dividing groove 91 is not formed in the peripheral portion 60 outside the outer peripheral edge 30a of the sealing portion 30 of the cell 50. it can.

  Further, in the photoelectric conversion element 100, all of the outer insulating material 33b enters each of the dividing grooves 91c, 91d, and 91e among the plurality of dividing grooves 91a to 91g. On the other hand, in each of the dividing grooves 91a, 91b, 91f, and 91g among the plurality of dividing grooves 91, the outer insulating material 33b partially enters. That is, each of the dividing grooves 91a, 91b, 91f, and 91g has a portion where the outer insulating material 33 does not enter. For this reason, a portion where the outer insulating material 33b enters partly and the outer insulating material 33b does not enter while sufficiently suppressing the penetration of moisture into the dividing grooves 91c, 91d, 91e into which the outer insulating material 33b has entered all. It is possible to promote the discharge of moisture from the insulating groove 90 by the dividing grooves 91a, 91b, 91f, and 91g. In particular, in the photoelectric conversion element 100, the dividing grooves 91a, 91b, 91f, and 91g are shorter than the dividing grooves 91c, 91d, and 91e, and the effect of promoting moisture discharge is high, and the shorter dividing grooves 91a, 91b, and 91f , 91g has a portion where the outer insulating material 33 does not enter. For this reason, the photoelectric conversion element 100 can discharge moisture more efficiently than the case where the length of the dividing grooves 91a, 91b, 91f, and 91g is longer than the length of the dividing grooves 91c, 91d, and 91e, and is durable. Can be improved sufficiently.

  Further, in the photoelectric conversion element 100, the plurality of dividing grooves 91b and 91c intersect at the dividing groove intersecting portion 92b, and the dividing grooves 91e and 91f intersect at the dividing groove intersecting portion 92e. For this reason, moisture is discharged from the plurality of dividing grooves 91 instead of only from one dividing groove 91 at the dividing groove intersecting portions 92 b and 92 e of the insulating groove 90. For this reason, the discharge of moisture from the insulating groove 90 can be more sufficiently promoted at the dividing groove intersecting portions 92b and 92e of the insulating groove 90.

  Next, the first external connection terminal 18a, the second external connection terminal 18b, the insulating material 33, the transparent substrate 11, the conductive portion 12, the peripheral portion 60, the counter electrode 20, the oxide semiconductor layer 13, the dye, the sealing portion 30, and the electrolyte 40 will be described in detail.

(First external connection terminal)
The first external connection terminal 18a includes a metal material. Examples of the metal material include silver, copper, and indium. You may use these individually or in combination of 2 or more types.

(Second external connection terminal)
The second external connection terminal 18b includes a metal material. As the metal material, the same material as the metal material included in the first external connection terminal 18a can be used.

(Insulating material)
The insulating material 33 may be made of an insulating material, but is preferably made of a material having a higher melting point than the material forming the sealing portion 30. For this reason, examples of the insulating material include inorganic insulating materials such as glass frit, thermosetting resins such as polyimide resins, and thermoplastic resins. Among these, it is preferable to use an inorganic insulating material such as glass frit or a thermosetting resin. In this case, even if the sealing portion 30 has fluidity at high temperatures, the insulating material 33 is less likely to fluidize even at high temperatures than in the case of being made of a thermoplastic resin. For this reason, the contact between the electrode 12A and the counter electrode 20 is sufficiently suppressed, and a short circuit between the electrode 12A and the counter electrode 20 can be sufficiently suppressed. Among these, inorganic insulating materials such as glass frit are preferable. In this case, the durability of the photoelectric conversion element 100 can be further improved as compared with the case where the insulating material is an organic insulating material. The thickness of the insulating material 33 from the transparent substrate 11 is usually 10 to 30 μm, preferably 15 to 25 μm.

The insulating material 33 may be colored or not colored, but is preferably colored. When the insulating material 33 is colored, the color of the insulating material 33 can be brought close to the color of the oxide semiconductor layer 13, and a better appearance can be realized. Here, "being colored" refers to L ^* of ^L * ^a * ^{b *} color space of the insulating material 33 is less than 35. Here, L ^* is defined by the following equation when the spectral reflectance at 700 nm with respect to CIE D65 standard light is x, 546.1 nm is y, and 435.8 nm is z.
L ^* = 116 × (0.2126z + 0.7152y + 0.0722x) ^1/3 −16

The color of the insulating material 33 is not particularly limited, and various colors can be used depending on the purpose. For example, if characters and designs are not displayed on the conductive portion 12 and the peripheral portion 60, the color of the insulating material 33 may be the same color as that of the oxide semiconductor layer 13. Here, the color of the same system means a color in which the difference between L ^* , a ^* , and b ^{* in} the L ^* a ^* b ^* color space is within ± 5.

(Transparent substrate)
The material which comprises the transparent substrate 11 should just be a transparent material, for example, As such a transparent material, glass, such as borosilicate glass, soda lime glass, white plate glass, quartz glass, polyethylene terephthalate (PET), for example , Polyethylene naphthalate (PEN), polycarbonate (PC), and polyethersulfone (PES). The thickness of the transparent substrate 11 is appropriately determined according to the size of the photoelectric conversion element 100 and is not particularly limited, but may be in the range of 50 μm to 10 mm, for example.

(Conductive part)
The conductive portion 12 is a portion serving as a path for current generated in the cell 50. Examples of the material constituting the conductive portion 12 include conductive metal oxides such as tin-added indium oxide (ITO), tin oxide (SnO ₂ ), and fluorine-added tin oxide (FTO). The conductive portion 12 may be a single layer or a laminated body of a plurality of layers containing different conductive metal oxides. When the electroconductive part 12 is comprised with a single layer, since the electroconductive part 12 has high heat resistance and chemical resistance, it is preferable that FTO is included. What is necessary is just to make the thickness of the electroconductive part 12 into the range of 0.01-2 micrometers, for example.

(Peripheral part)
The peripheral portion 60 is a portion that does not serve as a path for current generated in the cell 50. The material constituting the peripheral portion 60 may be a conductive material or an insulating material. As a material constituting the peripheral portion 60, for example, the same material as that constituting the conductive portion 12 can be used. Peripheral portion 60 may be a single layer or a laminate of a plurality of layers including different conductive metal oxides. The thickness of the peripheral portion 60 may be in the range of 0.01 to 2 μm, for example.

(Counter electrode)
The counter electrode 20 includes the metal substrate 21 and the catalyst layer 22 as described above.

  Although the metal substrate 21 should just be comprised with a metal, it is preferable that this metal is a metal which can form a passive state. In this case, since the metal substrate 21 is hardly corroded by the electrolyte 40, the photoelectric conversion element 100 can sufficiently improve the durability. Examples of the metal capable of forming a passive material include titanium, nickel, molybdenum, tungsten, aluminum, stainless steel, and alloys thereof. The thickness of the metal substrate 21 is appropriately determined according to the size of the photoelectric conversion element 100 and is not particularly limited, but may be, for example, 0.005 to 0.1 mm.

  The catalyst layer 22 is composed of platinum, a carbon-based material, a conductive polymer, or the like. Here, carbon black and carbon nanotubes are preferably used as the carbon-based material.

(Oxide semiconductor layer)
The oxide semiconductor layer 13 is composed of oxide semiconductor particles. Examples of the oxide semiconductor particles include titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), zinc oxide (ZnO), tungsten oxide (WO ₃ ), niobium oxide (Nb ₂ O ₅ ), and strontium titanate (SrTiO ₃ ). , Tin oxide (SnO ₂ ), or two or more of these.

  The thickness of the oxide semiconductor layer 13 is not particularly limited, but may be 0.1 to 100 μm, for example.

(Dye)
Examples of the dye include a ruthenium complex having a ligand including a bipyridine structure, a terpyridine structure, and the like, a photosensitizing dye such as an organic dye such as porphyrin, eosin, rhodamine, and merocyanine, and an organic such as a lead halide-based perovskite crystal. -An inorganic composite pigment | dye etc. are mentioned. For example, CH ₃ NH ₃ PbX ₃ (X = Cl, Br, I) is used as the lead halide perovskite. Among the above dyes, a ruthenium complex having a ligand containing a bipyridine structure or a terpyridine structure is preferable. In this case, the photoelectric conversion characteristics of the photoelectric conversion element 100 can be further improved. In addition, when using a photosensitizing dye as a pigment | dye, the photoelectric conversion element 100 turns into a dye-sensitized photoelectric conversion element.

(Sealing part)
The sealing part 30 is endless when the photoelectric conversion element 100 is viewed in a direction orthogonal to the one surface 11a of the transparent substrate 11, and has an opening on the inner side. The shape of the opening is not particularly limited, and examples of the shape of the opening include a circular shape and a polygonal shape such as a quadrangle.

  As a material constituting the sealing part 30, for example, an ionomer, an ethylene-vinyl acetic anhydride copolymer, an ethylene-methacrylic acid copolymer, an ethylene-vinyl alcohol copolymer, a modified polyolefin resin, an ultraviolet curable resin, And resin, such as a vinyl alcohol polymer, is mentioned.

  The thickness of the sealing part 30 is 20-90 micrometers normally, Preferably it is 40-80 micrometers.

(Electrolytes)
The electrolyte 40 includes a redox couple and an organic solvent. As the organic solvent, acetonitrile, methoxyacetonitrile, methoxypropionitrile, propionitrile, ethylene carbonate, propylene carbonate, diethyl carbonate, γ-butyrolactone, valeronitrile, pivalonitrile, and the like can be used. Examples of the redox pair include a redox pair containing a halogen atom such as iodide ion / polyiodide ion (for example, I ⁻ / I ₃ ⁻ ), bromide ion / polybromide ion, zinc complex, iron complex, cobalt complex, etc. The redox pair. The electrolyte 40 may use an ionic liquid instead of the organic solvent. As the ionic liquid, for example, a known iodine salt such as a pyridinium salt, an imidazolium salt, or a triazolium salt, and a room temperature molten salt that is in a molten state near room temperature is used. Examples of such room temperature molten salts include 1-hexyl-3-methylimidazolium iodide, 1-ethyl-3-propylimidazolium iodide, 1-ethyl-3-methylimidazolium iodide, 1, 2 -Dimethyl-3-propylimidazolium iodide, 1-butyl-3-methylimidazolium iodide, or 1-methyl-3-propylimidazolium iodide is preferably used.

  In addition, the electrolyte 40 may use a mixture of the ionic liquid and the organic solvent instead of the organic solvent.

  An additive can be added to the electrolyte 40. Examples of the additive include LiI, tetrabutylammonium iodide, 4-t-butylpyridine, guanidinium thiocyanate, 1-methylbenzimidazole, 1-butylbenzimidazole and the like.

Further, as the electrolyte 40, a nanocomposite gel electrolyte, which is a pseudo-solid electrolyte formed by kneading nanoparticles such as SiO ₂ , TiO ₂ , and carbon nanotubes to form a gel, may be used, and polyvinylidene fluoride, polyethylene oxide An electrolyte gelled using an organic gelling agent such as a derivative or an amino acid derivative may be used.

The electrolyte 40 includes a redox pair composed of iodide ions / polyiodide ions (for example, I ⁻ / I ₃ ⁻ ), and the concentration of polyiodide ions (for example, I ₃ ⁻ ) is 0.010 mol / liter or less. It is preferably 0.005 mol / liter or less, more preferably 2 × 10 ⁻⁴ mol / liter or less. In this case, since the concentration of polyiodide ions that carry electrons is low, the leakage current can be further reduced. For this reason, since an open circuit voltage can be increased more, a photoelectric conversion characteristic can be improved more.

  Next, a method for manufacturing the photoelectric conversion element 100 will be described with reference to FIG.

  First, a laminated body in which one continuous transparent conductive film is formed on one transparent substrate 11 is prepared.

  As a method for forming the transparent conductive film, sputtering, vapor deposition, spray pyrolysis, CVD, or the like is used.

  Next, as shown in FIG. 3, the insulating groove 90, the internal insulating groove 90 </ b> A and the dividing groove 91 are formed in the transparent conductive film, and the conductive portion 12 and the peripheral portion 60 are formed. At this time, the conductive portion 12 is formed to have the electrode 12A, the first current extraction portion 12B, and the second current extraction portion 12C by the insulating groove 90 and the internal insulating groove 90A. Further, the peripheral portion 60 is divided by a plurality of dividing grooves 91a to 91g, and is formed to have a plurality of divided peripheral portions 60A to 60H.

The insulating groove 90, the internal insulating groove 90A, and the dividing groove 91 can be formed by a laser scribing method using, for example, a YAG laser or a CO ₂ laser as a light source.

  Next, a precursor of the first external connection terminal 18a and a precursor of the second external connection terminal 18b are formed on the first current extraction unit 12B and the second current extraction unit 12C, respectively. The precursor of the first external connection terminal 18a and the precursor of the second external connection terminal 18b can be formed, for example, by applying a silver paste and drying.

  Furthermore, a region to which the sealing portion 30 is to be bonded (hereinafter referred to as “sealing portion bonding planned region”) and a region that surrounds the entire sealing portion bonding planned region (hereinafter referred to as “enclosing region”). ), The precursor of the insulating material 33 is formed in two projecting regions extending in opposite directions from the sealing portion adhesion planned region. At this time, since the insulating groove 90 is formed in the region where the sealing portion is to be bonded, the precursor of the insulating material 33 is formed so as to fill the entire insulating groove 90 and also cover the edge of the electrode 12A. The Further, in the projecting region of the surrounding region, a part of the electrode 12A, the first current extraction unit 12B, and the second current extraction unit 12C are covered and hidden, and the divided peripheral portions 60A, 60B, 60C, 60F, 60G, 60H are covered. A precursor of the insulating material 33 is formed so as to cover a part of. At this time, all of the precursor of the insulating material 33 enters the outer insulating groove 90 and the inner insulating groove 90A of the sealing portion 30, and all enters the dividing grooves 91c, 91d, 91e, and the dividing grooves 91a, 91b, 91f. , 91g is formed so that a part thereof enters. The precursor of the insulating material 33 can be formed by applying and drying a paste containing an insulating material, for example.

  Subsequently, a precursor of the oxide semiconductor layer 13 is formed on the electrode 12A.

  The precursor of the oxide semiconductor layer 13 is obtained by printing and drying an oxide semiconductor layer paste for forming the oxide semiconductor layer 13. In addition to titanium oxide, the oxide semiconductor layer paste includes a resin such as polyethylene glycol and ethyl cellulose and a solvent such as terpineol.

  As a printing method of the oxide semiconductor layer paste, for example, a screen printing method, a doctor blade method, a bar coating method, or the like can be used.

  Next, the precursor of the first external connection terminal 18a, the precursor of the second external connection terminal 18b, the precursor of the insulating material 33, and the precursor of the oxide semiconductor layer 13 are baked together to form the first external connection terminal. 18a, the second external connection terminal 18b, the insulating material 33, and the oxide semiconductor layer 13 are formed. At this time, the insulating material 33 has an inner insulating material 33a on the sealing portion formation scheduled region and an outer insulating material 33b on the protruding region.

  At this time, although the firing temperature varies depending on the type of oxide semiconductor particles and glass frit, it is usually 350 to 600 ° C., and the firing time also varies depending on the type of oxide semiconductor particles and the like, but usually 1 to 5 hours. is there. In this way, a working electrode is obtained.

  Next, a dye is supported on the oxide semiconductor layer 13 of the working electrode. For this purpose, for example, the working electrode is immersed in a solution containing a dye, the dye is adsorbed on the oxide semiconductor layer 13, and then the excess dye is washed away with the solvent component of the solution and dried. Good.

  Next, a sealing part forming body for forming the sealing part is prepared. The sealing part forming body can be obtained by preparing one sealing resin film made of a material constituting the sealing part and forming a rectangular opening in the sealing resin film. And this sealing part formation body is arrange | positioned on a sealing part adhesion plan area | region. At this time, since the inner insulating material 33a which is a part of the insulating material 33 is already provided on the sealing portion bonding scheduled region, the sealing portion forming body is overlapped with the inner insulating material 33a of the insulating material 33. Deploy.

  Next, the electrolyte 40 is disposed on the oxide semiconductor layer 13.

  Next, the counter electrode 20 is prepared. The counter electrode 20 can be obtained by forming the catalyst layer 22 on the metal substrate 21.

  Next, the sealing portion forming body and the counter electrode 20 are overlapped, and the sealing portion forming body is heated and melted while being pressurized. Thus, the sealing portion 30 is formed between the working electrode and the counter electrode 20. The formation of the sealing portion 30 may be performed under atmospheric pressure or under reduced pressure, but is preferably performed under reduced pressure.

  Next, a wiring material is formed so as to connect the metal substrate 21 of the cell 50 and the first current extraction portion 12B. Specifically, a paste containing a material constituting the wiring material is prepared, and this paste is applied so as to connect the metal substrate 21 and the first current extraction portion 12B and is cured, thereby forming the wiring material. .

  The photoelectric conversion element 100 is obtained as described above.

  In the above description, in order to form the first external connection terminal 18a, the second external connection terminal 18b, the insulating material 33, and the oxide semiconductor layer 13, the precursor of the first external connection terminal 18a, the second external connection The precursor of the terminal 18b, the precursor of the insulating material 33, and the precursor of the oxide semiconductor layer 13 are baked at once, but the first external connection terminal 18a and the second external connection terminal 18b, the insulating material 33 and the oxide semiconductor layer 13 may be formed by firing the precursor separately.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, the insulating material 33 is composed of the inner insulating material 33a and the outer insulating material 33b, but the insulating material 33 may be composed of only the inner insulating material 33a. Further, although the photoelectric conversion element 100 includes the insulating material 33, the photoelectric conversion element 100 does not necessarily include the insulating material 33.

  Furthermore, in the said embodiment, although the sealing part 30 is provided between the counter electrode 20 and the electrode 12A, the sealing part 30 should just be provided between the counter electrode 20 and the transparent substrate 11, and is not necessarily a counter electrode. 20 and the electrode 12A may not be provided.

  Further, in the above embodiment, when the photoelectric conversion element 100 is viewed in a direction orthogonal to the one surface 11a of the transparent substrate 11, the sealing portion 30 is disposed so as to partially overlap the insulating groove 90. The entire stop portion 30 may be disposed so as to overlap the insulating groove 90.

  Furthermore, in the said embodiment, although all the dividing grooves 91a-91g are formed in the peripheral part 60 on the outer side of the outer periphery 30a of the sealing part 30 of the cell 50, some of the dividing grooves 91a-91g Only the dividing grooves may be formed in the peripheral portion 60 outside the outer peripheral edge 30a of the sealing portion 30 of the cell 50, and any of the dividing grooves 91a to 91g is formed on the outer peripheral edge 30a of the sealing portion 30 of the cell 50. It does not need to be formed in the peripheral part 60 outside.

  Further, in the above embodiment, the outer insulating material 33b of the insulating material 33 enters all through the dividing grooves 91c, 91d, 91e, and a part of the outer insulating material 33b of the insulating material 33 partially enters the dividing grooves 91a, 91b, 91f, 91g. However, as in the photoelectric conversion element 200 shown in FIG. 4, the outer insulating material 33 b may enter all in each of the dividing grooves 91 a to 91 g.

  Further, in the above embodiment, the outer insulating material 33b of the insulating material 33 enters all in the dividing grooves 91c, 91d, 91e, and the outer insulating material 33b of the insulating material 33 is partly in the dividing grooves 91a, 91b, 91f, 91g. However, as in the photoelectric conversion element 300 shown in FIG. 5, the outer insulating material 33b of the insulating material 33 partially enters the dividing grooves 91c, 91d, and 91e and is insulated by the dividing grooves 91a, 91b, 91f, and 91g. The outer insulating material 33b of the material 33 may enter all.

  Furthermore, in the above-described embodiment, a part of the plurality of intersecting portions 92 is a dividing groove intersecting portion. However, all of the plurality of intersecting portions 92 may be constituted by a dividing groove intersecting portion, or a plurality of intersecting portions. All of 92 may not be constituted by the dividing groove intersection.

  In the above embodiment, the dividing grooves 91a, 91b, 91f, and 91g are shorter than the dividing grooves 91c, 91d, and 91e. However, the length of the dividing grooves 91a, 91b, 91f, and 91g is the dividing grooves 91c, 91d. , 91e or less.

  Furthermore, in the said embodiment, although the dividing groove 91 is comprised by the seven dividing grooves 91a-91g, if the number of the dividing grooves 91 is at least one, it will not specifically limit. However, the number of the dividing grooves 91 is preferably two or more. In this case, the resistance value between the counter electrode 20 as the positive electrode and the electrode 12A as the negative electrode can be increased as compared with the case where the number of the dividing grooves 91 is less than two, and the insulation between the positive electrode and the negative electrode can be increased. Can be improved. The number of the dividing grooves 91 is more preferably 5 or more from the viewpoint of further improving the insulation between the positive electrode and the negative electrode.

  In the above embodiment, the counter electrode 20 has the metal substrate 21 and the catalyst layer 22. However, if the photoelectric conversion element 100 does not have a back sheet that covers the cell 50 on the one surface 11 a side of the transparent substrate 11, the metal A transparent conductive substrate may be used instead of the substrate 21. In this case, the transparent substrate 11 and the conductive part 12 of the conductive substrate 15 are not necessarily transparent. For example, an opaque substrate or an opaque conductive portion may be used instead of the transparent substrate 11 or the conductive portion 12 of the conductive substrate 15.

  Moreover, in the said embodiment, although the oxide semiconductor layer 13 is provided on the electroconductive board | substrate 15, the oxide semiconductor layer 13 may be provided on the metal substrate 21 of the counter electrode 20 which is a 2nd board | substrate. However, in this case, the catalyst layer 22 is provided on the conductive substrate 15.

  Furthermore, in the said embodiment, although the one cell 50 is used, the photoelectric conversion element of this invention may have a some cell.

  In the above embodiment, an insulating substrate may be used as the second substrate instead of the counter electrode 20. In this case, a counter electrode is provided between the insulating substrate and the oxide semiconductor layer 13.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

Example 1
First, a laminate was prepared by forming a transparent conductive film made of FTO having a thickness of 0.6 μm on a transparent substrate made of glass having a thickness of 2.2 mm. Next, as shown in FIG. 3, an insulating groove 90, an internal insulating groove 90 </ b> A and a dividing groove 91 are formed in one continuous conductive film by a CO ₂ laser (V-460 manufactured by Universal System Co., Ltd.). And the peripheral part 60 was formed. At this time, the peripheral portion 60 was divided into a plurality of divided peripheral portions 60A to 60H by forming the dividing grooves 91a to 91g. The widths of the insulating groove 90, the internal insulating groove 90A, and the dividing groove 91 were set to 0.1 mm. Furthermore, the length of the dividing grooves 91c, 91d, 91e was 2.5 mm, and the length of the dividing grooves 91a, 91b, 91f, 91g was 1 mm.

  Further, a precursor of the first external connection terminal 18a and a precursor of the second external connection terminal 18b for taking out the current to the outside were formed on the first current extraction portion 12f and the second current extraction portion 12h, respectively. The precursors of the first external connection terminal 18a and the second external connection terminal 18b were formed by applying a silver paste by screen printing and drying.

  Furthermore, the precursor of the insulating material 33 was formed in the sealing part adhesion plan area and two projecting areas projecting in opposite directions to each other in the surrounding area. At this time, the precursor of the insulating material 33 covers all of the dividing peripheral portions 60D and 60E, the first current extracting portion 12B, the second current extracting portion 12C, and the electrode 12A protruding outside the sealing portion 30, and the dividing periphery. By covering only part of the portions 60A to 60C and 60F to 60H, the dividing grooves 91c, 91d and 91e, the insulating groove 90 and the internal insulating groove 90A are all covered, and the dividing grooves 91a, 91b, 91f and 91g are integrated. Only the part was covered. The insulating material 33 was formed by applying and drying a paste containing glass frit by screen printing.

  Further, a precursor of the oxide semiconductor layer 13 was formed on the electrode 12A. At this time, the precursor of the oxide semiconductor layer 13 was obtained by applying a titanium oxide nanoparticle paste containing titanium oxide by screen printing and drying at 150 ° C. for 10 minutes.

  Next, the precursor of the first external connection terminal 18a and the second external connection terminal 18b, the precursor of the insulating material 33, and the precursor of the oxide semiconductor layer 13 are baked at 460 ° C. for 90 minutes, and then cooled to room temperature. Then, the first external connection terminal 18a, the second external connection terminal 18b, the insulating material 33, and the oxide semiconductor layer 13 were formed. At this time, the insulating material 33 covered all of the dividing grooves 91c, 91d, 91e, the insulating groove 90, and the internal insulating groove 90A, and only partially covered the dividing grooves 91a, 91b, 91f, 91g. Such a covering state of the insulating material 33 was defined as “partial covering 1”. Thus, a working electrode having the conductive substrate 15 was obtained.

  Next, the working electrode obtained as described above is immersed overnight in a dye solution containing a photosensitizing dye composed of Z907 and a solvent mixed with acetonitrile and tert-butanol. After that, it was taken out and dried, and a photosensitizing dye was supported on the oxide semiconductor layer 13.

  Next, the sealing part formation body for forming a sealing part was prepared. The sealing part forming body is prepared by preparing one sealing resin film made of maleic anhydride-modified polyethylene (trade name: Binnel, manufactured by DuPont) of 10.1 cm × 4.6 cm × 50 μm. It was obtained by forming a rectangular opening in the resin film. At this time, the sealing part forming body was manufactured so that the opening had a size of 9.7 cm × 4.2 cm × 50 μm. And this sealing part formation body was set | placed on the insulating material 33 on a working electrode.

Next, an electrolyte 40 obtained by adding 3-methoxypropionitrile to a mixture containing 1,2-dimethylpropylimidazolium iodide and I ₂ was dropped onto the oxide semiconductor layer 13.

  Next, a counter electrode 20 was prepared. The counter electrode 20 was prepared by forming a catalyst layer 22 made of platinum having a thickness of 5 nm on a metal substrate 21 made of a titanium foil of 10.0 cm × 4.6 cm × 50 μm by a sputtering method.

  And the sealing part formation body and the counter electrode 20 were made to oppose, and the sealing part formation body and the counter electrode 20 were piled up. And the sealing part formation body was heat-melted at 190 degreeC with the hot press, pressing the sealing part formation body in this state. Thus, the sealing portion 30 was formed between the working electrode and the counter electrode 20.

  Next, the wiring material was formed by apply | coating and hardening a silver paste so that the 2nd electric current extraction part 12C and the metal substrate 21 of the cell 50 might be connected.

  A photoelectric conversion element was obtained as described above.

(Example 2)
When the precursor of the insulating material 33 is formed, the precursor of the insulating material 33 is covered by the precursor of the insulating material 33 so that the precursor of the insulating material 33 is entirely contained in the dividing grooves 91a to 91g. A photoelectric conversion element 200 shown in FIG. 4 was produced in the same manner as in Example 1 except that it entered. Note that the outer insulating material 33b does not necessarily show through the dividing groove 91 of the underlying conductive substrate 15, but in FIG. 4, it is easy to understand the positional relationship between the outer insulating material 33b and the dividing groove 91. Therefore, the dividing groove 91 is shown so as to be seen through.

Example 3
When forming the precursor of the insulating material 33, the precursor of the insulating material 33 covers the electrode 12A protruding to the outside of the sealing portion 30, the divided peripheral portions 60B and 60G, and the divided peripheral portions 60A, 60C, 60D, 60E, 60F, and 60H are partially covered, and the first current extraction portion 12B and the second current extraction portion 12C are only partially covered, whereby the precursor of the insulating material 33 is separated into the dividing grooves 91a, 91b, 91f, The photoelectric conversion element 300 shown in FIG. 5 is the same as in Example 1 except that the entire 91 g is covered and only a part of the dividing grooves 91 c, 91 d, 91 e, the insulating groove 90, and the inner insulating groove 90 A is covered. Was made. In the obtained photoelectric conversion element 300, the insulating material 33 covers all the dividing grooves 91a, 91b, 91f, and 91g, and covers only a part of the dividing grooves 91c, 91d, and 91e, the insulating groove 90, and the internal insulating groove 90A. It was. Such a covering state of the insulating material 33 was defined as “partial covering 2”. Note that the outer insulating material 33b does not necessarily show through the dividing groove 91 of the underlying conductive substrate 15, but in FIG. 5, it is easy to understand the positional relationship between the outer insulating material 33b and the dividing groove 91. Therefore, the dividing groove 91 is shown so as to be seen through.

Example 4
When the dividing groove 91 is formed in one transparent conductive film, the dividing portion 91a, 91b, 91f, 91g is not formed, but only the dividing grooves 91c, 91d, 91e are formed, so that the peripheral portion 60 is divided into a plurality of divided peripheral portions. When dividing the portions 60A, 60D, 60E, and 60H to form the precursor of the insulating material 33, the insulating material 33 is covered with the precursor of the insulating material 33 to cover all of the divided peripheral portions 60A, 60D, 60E, and 60H. A photoelectric conversion element 400 shown in FIG. 6 was produced in the same manner as in Example 1 except that the precursor of No. 1 entered all through the dividing grooves 91c, 91d, and 91e. Note that the outer insulating material 33b does not necessarily see through the dividing groove 91 of the conductive substrate 15 below, but in FIG. 6, it is easy to understand the positional relationship between the outer insulating material 33b and the dividing groove 91. Therefore, the dividing groove 91 is shown so as to be seen through.

(Example 5)
When the dividing groove 91 is formed in one transparent conductive film, the dividing portion 91a is not formed, but only the dividing groove 91d is formed without forming the dividing grooves 91a, 91b, 91c, 91f, 91g. When the precursor of the insulating material 33 is formed by being divided into the portions 60A and 60H, the precursor of the insulating material 33 is formed by covering all of the divided peripheral portions 60A and 60H with the precursor of the insulating material 33. A photoelectric conversion element 500 shown in FIG. 7 was manufactured in the same manner as in Example 1 except that the entire portion was cut in the dividing groove 91d. Note that the outer insulating material 33b does not necessarily see through the dividing groove 91 of the conductive substrate 15 below, but in FIG. 7, it is easy to understand the positional relationship between the outer insulating material 33b and the dividing groove 91. Therefore, the dividing groove 91 is shown so as to be seen through.

(Comparative Example 1)
When the dividing groove 91 is formed in one transparent conductive film, the peripheral portion 60 is not divided by the dividing groove 91, and when the precursor of the insulating material 33 is formed, the precursor of the insulating material 33 is used to form the peripheral portion 60. A photoelectric conversion element 600 shown in FIG. 8 was produced in the same manner as in Example 1 except that the entire structure was covered. Note that the outer insulating material 33b does not necessarily show through the dividing groove 91 of the underlying conductive substrate 15, but in FIG. 8, it is easy to understand the positional relationship between the outer insulating material 33b and the dividing groove 91. Therefore, the dividing groove 91 is shown so as to be seen through.

Example 6
A photoelectric conversion element was produced in the same manner as in Example 1 except that the precursor of the insulating material 33 was not formed.

(Example 7)
A photoelectric conversion element was produced in the same manner as in Example 4 except that the precursor of the insulating material 33 was not formed.

(Example 8)
A photoelectric conversion element was produced in the same manner as in Example 5 except that the precursor of the insulating material 33 was not formed.

(Comparative Example 2)
A photoelectric conversion element was produced in the same manner as in Comparative Example 1 except that the precursor of the insulating material 33 was not formed.

[Characteristic evaluation]
The photoelectric conversion elements of Examples 1 to 8 and Comparative Examples 1 and 2 obtained as described above were evaluated for durability and insulation between the positive electrode and the negative electrode.

(durability)
The outputs (η ₀ ) of the photoelectric conversion elements obtained in Examples 1 to 5 and Comparative Example 1 were measured. Subsequently, for the photoelectric conversion elements obtained in Examples 1 to 5 and Comparative Example 1, the first external connection terminal 18a and the second external connection terminal 18b were replaced with a polyimide tape (trade name: tesa 67350, manufactured by tesa). After waterproofing by sticking on one external connection terminal, the counter electrode 20 is not submerged and the first current extraction unit 12B and the second current extraction unit 12C are submerged and left for 90 hours, and then output (η ) Was measured. And the following formula:
Output retention rate (%) = η / η ₀ × 100
Based on the above, the output retention rate (output retention rate) was calculated. The results are shown in Table 1. The output retention rate was measured in the same manner for the photoelectric conversion elements obtained in Examples 6 to 8 and Comparative Example 2. The results are shown in Table 2.

(Insulation between positive and negative electrodes)
For the photoelectric conversion elements obtained in Examples 1 to 5 and Comparative Example 1, the resistance value between the first external connection terminal 18a and the second external connection terminal 18b was measured in a dark place covered with a black screen (trade name: The resistance value between the positive electrode (counter electrode 20) and the negative electrode (electrode 12A) was measured by using KT-2011, manufactured by Kaise Co., Ltd., and this resistance value was used as an index of insulation between the positive electrode and the negative electrode. . The results are shown in Table 1. For the photoelectric conversion elements obtained in Examples 6 to 8 and Comparative Example 2, similarly, the resistance value between the positive electrode and the negative electrode is measured by measuring the resistance between the first external connection terminal 18a and the second external connection terminal 18b. It was measured. The results are shown in Table 2.

  As shown in Table 1, in the photoelectric conversion elements of Examples 1 to 5, the output retention rate was sufficiently larger than that of the photoelectric conversion element of Comparative Example 1. Further, as shown in Table 2, in the photoelectric conversion elements of Examples 6 to 8, the output retention rate was sufficiently higher than that of the photoelectric conversion element of Comparative Example 2.

  From the above results, it was confirmed that the photoelectric conversion element of the present invention can improve durability.

11 ... Transparent substrate (first substrate)
12 ... Conductive part 12A ... Electrode (conductive part)
12B ... 1st current extraction part (conductive part)
12C ... 2nd current extraction part (conductive part)
20 ... Counter electrode (second substrate)
DESCRIPTION OF SYMBOLS 30 ... Sealing part 30a ... Outer peripheral edge of sealing part 33 ... Insulating material 50 ... Photoelectric conversion cell 60 ... Peripheral part 60a ... Outer peripheral edge of peripheral part 60A-60H ... Dividing peripheral part 90 ... Insulating groove 91, 91a-91g ... Dividing grooves 92a, 92b, 92d, 92e, 92g ... intersections 92b, 92e ... dividing grooves intersecting parts 100 to 500 ... photoelectric conversion elements

Claims (4)

A first substrate;
A conductive portion provided on one surface of the first substrate;
A peripheral portion provided along the periphery of the conductive portion on one surface of the first substrate;
The conductive part is a photoelectric conversion element having an electrode,
Having a photoelectric conversion cell;
The photoelectric conversion cell is
The electrode;
A second substrate facing the electrode;
A sealing portion for joining the first substrate and the second substrate;
The conductive portion and the peripheral portion are disposed via an insulating groove,
When the photoelectric conversion element is viewed in a direction perpendicular to the one surface of the first substrate, at least a part of the sealing portion is disposed so as to overlap the insulating groove,
The photoelectric conversion element, wherein the peripheral portion is divided into a plurality of divided peripheral portions by at least one dividing groove that communicates with the insulating groove and extends from the insulating groove to an outer peripheral edge of the peripheral portion.   The photoelectric conversion element according to claim 1, wherein the dividing groove is formed in the peripheral portion outside the outer peripheral edge of the sealing portion of the photoelectric conversion cell.   3. The photoelectric device according to claim 1, wherein the insulating groove has at least one intersecting portion intersecting the dividing groove, and the intersecting portion includes a dividing groove intersecting portion where a plurality of the dividing grooves intersect each other. Conversion element. An insulating material provided on one surface of the first substrate;
The said at least 1 parting groove | channel is comprised by the 1st parting groove | channel where the said insulating material penetrates all, and the 2nd parting groove | channel where the said insulating material does not penetrate | invade all. The photoelectric conversion element as described.

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