JP2018037555A - Method for manufacturing photoelectric conversion element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing photoelectric conversion element, by which a photoelectric conversion element having superior durability can be manufactured.SOLUTION: A method for manufacturing a photoelectric conversion element 100 comprises: an oxide semiconductor layer formation step of forming an oxide semiconductor layer 30 on an electrode substrate 10 or a counter substrate 20; a sealant fixing step of fixing an annular sealant to form a sealing part 40 on at least one of the electrode substrate 10 and the counter substrate 20; a pigment adsorption step of having a pigment adsorbed by an oxide semiconductor layer 30; an electrolyte-disposing step of disposing an electrolyte 50 on the electrode substrate 10 or the counter substrate 20; and a bonding step of bonding the electrode substrate 10 and the counter substrate 20 together through the sealant. The sealant fixed to at least one of the electrode substrate 10 and the counter substrate 20 includes oxygen-absorbing particles 40a.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a photoelectric conversion element.

  As a photoelectric conversion element, a photoelectric conversion element using a dye is attracting attention because it is inexpensive and high photoelectric conversion efficiency is obtained, and various developments have been made on photoelectric conversion elements using a dye.

  As a photoelectric conversion element using such a dye, for example, a dye-sensitized solar cell disclosed in Patent Document 1 below is known. In the following Patent Document 1, two electrode substrates facing each other, an annular sealing portion that joins the two electrode substrates, and a cell space formed by the two electrode substrates and the sealing portion are arranged. And a sealing portion provided on the outer side of the electrolyte solution layer and a gas-resistant layer for suppressing gas permeation. A sensitized solar cell is disclosed.

JP 2007-294387 A

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

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

  The present inventors examined the cause of the above problem in the dye-sensitized solar cell described in Patent Document 1. As a result, in the dye-sensitized solar cell described in Patent Document 1, since the gas-resistant permeation layer is in contact with the outside air, oxygen gas is easily absorbed, and the oxygen absorption capacity reaches a saturated state at an early stage. The present inventors thought that oxygen outside the stop portion permeates the sealing portion and easily enters the electrolyte, and as a result, the power generation performance of the photoelectric conversion element starts to deteriorate early. . Therefore, as a result of further earnest studies, the present inventors have found that the above-described problems can be solved by the following invention.

  That is, the present invention includes an electrode substrate, a counter substrate facing the electrode substrate, an oxide semiconductor layer provided on the electrode substrate or the counter substrate, a dye adsorbed on the oxide semiconductor layer, and the electrode An annular sealing portion that joins the substrate and the counter substrate and surrounds the oxide semiconductor layer, and an electrolyte that is disposed in a cell space formed by the electrode substrate, the counter substrate, and the sealing portion. And a method of manufacturing a photoelectric conversion element in which the sealing portion manufactures a photoelectric conversion element containing oxygen-absorbing particles, wherein the oxide semiconductor layer forms the oxide semiconductor layer on the electrode substrate or the counter substrate. A forming step, a sealing material fixing step of fixing an annular sealing material forming the sealing portion on at least one of the electrode substrate and the counter substrate, and a dye that adsorbs the dye to the oxide semiconductor layer Suck A step of arranging the electrolyte on the electrode substrate or the counter substrate, and a bonding step of bonding the electrode substrate and the counter substrate through the sealing material. And the said sealing material fixed to at least one among the said opposing board | substrates is a manufacturing method of a photoelectric conversion element containing oxygen absorption particles.

  According to the method for producing a photoelectric conversion element of the present invention, in the obtained photoelectric conversion element, the sealing portion contains oxygen absorbing particles. That is, oxygen absorbing particles are present in the sealing portion. For this reason, in the obtained photoelectric conversion element, oxygen that enters from the outside of the sealing portion is sufficiently absorbed by the oxygen-absorbing particles. For this reason, compared with the case where the sealing part does not contain oxygen-absorbing particles, it is sufficiently suppressed that oxygen penetrates the sealing part from the outside of the sealing part and enters the electrolyte. In the sealing material fixing step, oxygen absorbing particles are included in the form of particles in the sealing material fixed to at least one of the electrode substrate and the counter substrate. For this reason, in the process from a sealing material fixing process to a photoelectric conversion element being obtained, it is fully suppressed that oxygen absorption particles touch external air. That is, oxygen is sufficiently suppressed from being absorbed by the oxygen-absorbing particles in the process from the sealing material fixing step until the photoelectric conversion element is obtained. For this reason, in the obtained photoelectric conversion element, the time until the oxygen absorption capacity of the oxygen absorbing particles reaches a saturated state is sufficiently secured, and the power generation performance of the photoelectric conversion element is sufficiently suppressed from starting to deteriorate early. . Therefore, according to the method for manufacturing a photoelectric conversion element of the present invention, it is possible to manufacture a photoelectric conversion element having excellent durability.

  In the manufacturing method, in the sealing material fixing step, the sealing material is fixed to the electrode substrate as a first sealing material, the sealing material is fixed to the counter substrate as a second sealing material, It is preferable that the content rate (volume%) of the oxygen absorbing particles in the first sealing material is different from the content rate (volume%) of the oxygen absorbing particles in the second sealing material.

  In this case, among the first sealing material and the second sealing material, the sealing material having a smaller content rate of oxygen absorbing particles is compared with the sealing material having a higher content rate of oxygen absorbing particles, or the electrode substrate or It has better adhesion to the counter substrate. Therefore, the content rate of the oxygen absorbing particles in the first sealing material and the second sealing material is large, the content rate of the oxygen absorbing particles in the first sealing material and the content of the oxygen absorbing particles in the second sealing material. Compared with the case where a rate is the same, in the photoelectric conversion element obtained, the sealing part has more excellent adhesiveness with respect to an electrode substrate and a counter substrate. Therefore, the photoelectric conversion element obtained by the production method of the present invention can have more excellent durability.

  In the manufacturing method, in the oxide semiconductor layer formation step, the oxide semiconductor layer is formed on the electrode substrate, and the sealing material fixing step is performed between the oxide semiconductor layer formation step and the dye adsorption step. In the dye adsorption step, the dye semiconductor is adsorbed on the oxide semiconductor layer by bringing the electrode substrate on which the oxide semiconductor layer and the first sealing material are formed into contact with a dye solution, In the sealing material fixing step, the content (volume%) of the oxygen absorbing particles in the first sealing material is smaller than the content (volume%) of the oxygen absorbing particles in the second sealing material. It is preferable.

  In this case, in the sealing material fixing step, the first sealing material having a smaller content of oxygen-absorbing particles is fixed on the electrode substrate on which the oxide semiconductor layer is formed. And in a pigment | dye adsorption process, a pigment | dye is adsorb | sucked to an oxide semiconductor layer when the electrode substrate in which the oxide semiconductor layer and the 1st sealing material were formed is contacted with a pigment | dye solution. At this time, the content rate of the oxygen absorbing particles in the first sealing material is smaller than the content rate of the oxygen absorbing particles in the second sealing material. For this reason, even if a 1st sealing material contacts with a pigment | dye solution, there is little quantity of the pigment | dye adsorb | sucked to the oxygen absorption particle in a 1st sealing material. On the other hand, since the second sealing material does not come into contact with the dye solution, the dye does not adsorb to the oxygen-absorbing particles in the second sealing material, and sufficient oxygen-absorbing ability is secured in the oxygen-absorbing particles. Therefore, in the obtained photoelectric conversion element, the time until the oxygen absorption capacity of the oxygen absorbing particles in the sealing portion reaches a saturated state is extended, and it is sufficiently suppressed that the power generation performance of the photoelectric conversion element starts to deteriorate early. The Therefore, the manufacturing method of the photoelectric conversion element of this invention can manufacture the photoelectric conversion element which has the more outstanding durability.

  In the said manufacturing method, it is preferable that the content rate of the said oxygen absorption particle in a said 1st sealing material is 0 volume%.

  In this case, in the sealing material fixing step, the first sealing material in which the content of oxygen-absorbing particles is 0% by volume is fixed on the electrode substrate on which the oxide semiconductor layer is formed. And in a pigment | dye adsorption process, a pigment | dye is adsorb | sucked to an oxide semiconductor layer when the electrode substrate in which the oxide semiconductor layer and the 1st sealing material were formed is contacted with a pigment | dye solution. At this time, the content rate of the oxygen absorbing particles in the first sealing material is 0% by volume. For this reason, even if a 1st sealing material contacts with a pigment | dye solution, there is no pigment | dye adsorb | sucked to the oxygen absorption particle in a 1st sealing material. On the other hand, since the second sealing material does not come into contact with the dye solution, the dye does not adsorb to the oxygen-absorbing particles in the second sealing material, and sufficient oxygen-absorbing ability is secured in the oxygen-absorbing particles. Therefore, in the obtained photoelectric conversion element, the time until the oxygen absorption capacity of the oxygen absorbing particles in the sealing portion reaches a saturated state is prolonged, and the power generation performance of the photoelectric conversion element is more sufficiently suppressed from starting earlier. Is done. Therefore, the method for producing a photoelectric conversion element of the present invention can produce a photoelectric conversion element having further excellent durability.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the photoelectric conversion element which can manufacture the photoelectric conversion element which has the outstanding durability is provided.

It is sectional drawing which shows the photoelectric conversion element obtained by 1st Embodiment of the manufacturing method of the photoelectric conversion element which concerns on this invention. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG. It is sectional drawing which shows the photoelectric conversion element obtained by 2nd Embodiment of the manufacturing method of the photoelectric conversion element which concerns on this invention. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG. It is a cut surface end view which shows 1 process of the manufacturing method of the photoelectric conversion element of FIG.

  Hereinafter, embodiments of a method for producing a photoelectric conversion element of the present invention will be described in detail with reference to the drawings.

<First Embodiment>
First, prior to the description of the first embodiment of the method for manufacturing a photoelectric conversion element according to the present invention, the photoelectric conversion element manufactured by the first embodiment of the method for manufacturing a photoelectric conversion element of the present invention will be described with reference to FIG. To do. FIG. 1 is a cross-sectional view showing a photoelectric conversion element obtained by the first embodiment of the method for manufacturing a photoelectric conversion element according to the present invention.

  As shown in FIG. 1, the photoelectric conversion element 100 includes one photoelectric conversion cell 60. The photoelectric conversion cell 60 includes an electrode substrate 10, a counter substrate 20 facing the electrode substrate 10, an annular sealing portion 40 that bonds the electrode substrate 10 and the counter substrate 20, and an oxide semiconductor provided on the electrode substrate 10. A layer 30; a dye adsorbed on the oxide semiconductor layer 30; and an electrolyte 50 disposed in a cell space formed by the electrode substrate 10, the counter substrate 20, and the sealing portion 40.

  The electrode substrate 10 includes a transparent substrate 11 and a transparent conductive layer 12 provided on the transparent substrate 11.

  The counter substrate 20 includes a conductive substrate 21 that also serves as a substrate and an electrode, and a conductive catalyst layer 22.

  The sealing portion 40 is configured by an annular first sealing portion 41 provided on the electrode substrate 10 and an annular second sealing portion 42 provided on the counter substrate 20. The first sealing portion 41 and the second sealing portion 42 are bonded to each other. Moreover, the 2nd sealing part 42 contains the oxygen absorption particle 40a. The content rate R1 (volume%) of the oxygen absorbing particles 40a in the first sealing part 41 is smaller than the content rate R2 (volume%) of the oxygen absorbing particles 40a in the second sealing part 42.

  Next, the electrode substrate 10, the counter substrate 20, the oxide semiconductor layer 30, the dye, the sealing portion 40, and the electrolyte 50 will be described in detail.

(Electrode substrate)
As described above, the electrode substrate 10 includes the transparent substrate 11 and the transparent conductive layer 12 provided on the transparent substrate 11.

  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 a range of 0.05 to 40 mm, for example.

Examples of the material constituting the transparent conductive layer 12 include conductive metal oxides such as tin-added indium oxide (ITO), tin oxide (SnO ₂ ), and fluorine-added tin oxide (FTO). The transparent conductive layer 12 may be a single layer or a laminate of a plurality of layers made of different conductive metal oxides. When the transparent conductive layer 12 is composed of a single layer, the transparent conductive layer 12 is preferably composed of FTO because it has high heat resistance and chemical resistance. Although the thickness of the transparent conductive layer 12 is not specifically limited, For example, what is necessary is just to make it the range of 0.01-2 micrometers.

(Opposite substrate)
As described above, the counter substrate 20 includes the conductive substrate 21 serving as a substrate and an electrode, and the conductive catalyst layer 22.

  The conductive substrate 21 is made of a corrosion-resistant metal material such as titanium, nickel, platinum, molybdenum, tungsten, aluminum, and stainless steel. The conductive substrate 21 may be formed of a laminate in which a substrate and an electrode are separated and a transparent conductive layer made of a conductive oxide such as ITO or FTO is formed as an electrode on the above-described insulating transparent substrate. The thickness of the conductive 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, 5 to 4000 μm.

  The catalyst layer 22 is composed of platinum, a carbon-based material, a conductive polymer, or the like. Here, carbon nanotubes are suitably used as the carbon-based material. Note that the counter substrate 20 may not have the catalyst layer 22 when the conductive substrate 21 has a catalytic function (for example, when carbon is included).

(Oxide semiconductor layer)
The oxide semiconductor layer 30 is composed of oxide semiconductor particles. Examples of the oxide semiconductor particles include titanium oxide (TiO ₂ ), zinc oxide (ZnO), tungsten oxide (WO ₃ ), niobium oxide (Nb ₂ O ₅ ), strontium titanate (SrTiO ₃ ), and tin oxide (SnO ₂ ). , Indium oxide (In ₃ O ₃ ), zirconium oxide (ZrO ₂ ), thallium oxide (Ta ₂ O ₅ ), lanthanum oxide (La ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), holmium oxide (Ho ₂ O) ₃ ), bismuth oxide (Bi ₂ O ₃ ), cerium oxide (CeO ₂ ), aluminum oxide (Al ₂ O ₃ ), or two or more thereof. The thickness of the oxide semiconductor layer 30 is not particularly limited, but may be 0.1 to 100 μm, for example.

(Dye)
Examples of the dye include a photosensitizing dye such as a ruthenium complex having a ligand containing a bipyridine structure, a terpyridine structure, or the like, an organic dye such as porphyrin, eosin, rhodamine, or merocyanine, and an organic- Examples include inorganic composite dyes. For example, CH ₃ NH ₃ PbX ₃ (X = Cl, Br, I) is used as the lead halide perovskite. Here, when a photosensitizing dye is used as the dye, the photoelectric conversion element 100 is a dye-sensitized photoelectric conversion element, and the photoelectric conversion cell 60 is a dye-sensitized photoelectric conversion cell.

  Among the above dyes, a photosensitizing dye composed of 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.

(Sealing part)
The sealing part 40 contains a sealing material and oxygen absorbing particles 40a. The sealing material is not particularly limited, and examples of the sealing material include thermoplastic resins such as modified polyolefin resin and vinyl alcohol polymer. Examples of modified polyolefin resins include ionomers, ethylene-vinyl acetic anhydride copolymers, ethylene-methacrylic acid copolymers, and ethylene-vinyl alcohol copolymers. These resins can be used alone or in combination of two or more. Among these, a modified polyolefin resin is preferable. In this case, the adhesion to the electrode substrate 10 and the counter substrate 20 is further increased.

  As described above, the sealing portion 40 includes the first sealing portion 41 and the second sealing portion 42. However, the sealing materials in the first sealing portion 41 and the second sealing portion 42 are mutually different. It may be composed of different materials or may be composed of the same material.

  The oxygen-absorbing particles 40a are not particularly limited as long as the oxygen-absorbing particles 40a have higher oxygen absorbability than the sealing material. Examples of the oxygen absorbing particles 40a include cerium-based oxygen absorbing particles, iron-based oxygen absorbing particles, cobalt-based oxygen absorbing particles, and organic oxygen-absorbing particles. Of these, cerium-based oxygen-absorbing particles are preferred because no moisture is required for the oxygen-absorbing reaction.

  Examples of the cerium-based oxygen absorbing particles include cerium oxide.

  Examples of the iron-based oxygen absorbing particles include reduced iron powder.

  Examples of the cobalt-based oxygen absorbing particles include cobalt naphthenate.

  Examples of organic oxygen absorbing particles include ascorbic acids.

  The difference (R2−R1) between the content R2 (volume%) of the oxygen absorbing particles 40a in the second sealing portion 42A and the content ratio R1 (volume%) of the oxygen absorbing particles 40a in the first sealing portion 41 is It is preferable that it is 2 volume% or more. In this case, the adhesiveness of the first sealing portion 41 can be further improved than the adhesiveness of the second sealing portion 42. (R2-R1) is more preferably 10% by volume or more. It is particularly preferable that the first sealing portion 41 does not contain the oxygen absorbing particles 40a. In this case, the adhesiveness of the first sealing portion 41 can be further improved than the adhesiveness of the second sealing portion 42. Therefore, in the photoelectric conversion element 100, the adhesiveness of the sealing part 40 with respect to the electrode substrate 10 and the counter substrate 20 can be further improved.

  The content R2 (volume%) of the oxygen absorbing particles 40a in the second sealing portion 42 is particularly limited as long as it is larger than the content R1 (volume%) of the oxygen absorbing particles 40a in the first sealing portion 41. Although it is not, it is preferable that it is 2 volume% or more. In this case, oxygen entering from the outside of the sealing portion 40 is sufficiently absorbed by the oxygen absorbing particles 40a. For this reason, the durability of the photoelectric conversion element 100 can be further improved. R2 is preferably 10% by volume or more. However, R2 is preferably 90% by volume or less. In this case, the adhesion of the sealing portion 40 to the electrode substrate 10 and the counter substrate 20 can be further improved. R2 is preferably 50% by volume or less.

(Electrolytes)
The electrolyte 50 includes, for example, a redox couple and an organic solvent. As the organic solvent, acetonitrile, methoxyacetonitrile, methoxypropionitrile, propionitrile, ethylene carbonate, propylene carbonate, diethyl carbonate, γ-butyrolactone, valeronitrile 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, and the like. And redox pairs. The iodide ion / polyiodide ion can be formed by iodine (I ₂ ) and a salt (ionic liquid or solid salt) containing iodide (I ⁻ ) as an anion. When using an ionic liquid having an iodide as an anion, only iodine should be added. When using an ionic liquid other than an organic solvent or an anion as an anion, an anion such as LiI or tetrabutylammonium iodide is used. A salt containing iodide (I ⁻ ) may be added.

  The electrolyte 50 may be 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.

  The electrolyte 50 may be a mixture of the ionic liquid and the organic solvent instead of the organic solvent.

  An additive can be added to the electrolyte 50. Examples of the additive include LiI, 4-t-butylpyridine, guanidinium thiocyanate, 1-methylbenzimidazole, 1-butylbenzimidazole and the like.

Furthermore, as the electrolyte 50, a nanocomposite gel electrolyte which is a pseudo-solid electrolyte obtained by kneading nanoparticles such as SiO ₂ , TiO ₂ , and carbon nanotubes with the above electrolyte may be used, and polyvinylidene fluoride may be used. Alternatively, an electrolyte gelled with an organic gelling agent such as a polyethylene oxide derivative or an amino acid derivative may be used.

  Next, a method for manufacturing the above-described photoelectric conversion element 100 will be described with reference to FIGS. 2 to 6 are sectional end views showing a series of steps of the first embodiment of the method for manufacturing a photoelectric conversion element according to the present invention.

<Preparation process>
First, the electrode substrate 10 and the counter substrate 20 are prepared. The electrode substrate 10 can be obtained by forming the transparent conductive layer 12 on the transparent substrate 11. As a method for forming the transparent conductive layer 12, a sputtering method, a vapor deposition method, a spray pyrolysis method, a CVD method, or the like is used.

  The counter substrate 20 can be obtained by forming the catalyst layer 22 on the conductive substrate 21. As a method for forming the catalyst layer 22, a sputtering method, a vapor deposition method, or the like is used. Of these, sputtering is preferred from the viewpoint of film uniformity.

<Oxide semiconductor layer formation process>
Next, as illustrated in FIG. 2, the oxide semiconductor layer 30 is formed over the electrode substrate 10. The oxide semiconductor layer 30 can be formed by printing an oxide semiconductor layer forming paste on the electrode substrate 10 and then baking the paste.

  The oxide semiconductor layer forming paste includes a resin such as polyethylene glycol and a solvent such as terpineol in addition to the oxide semiconductor particles described above. As a method for printing the oxide semiconductor layer forming paste, for example, a screen printing method, a doctor blade method, a bar coating method, or the like can be used.

  The firing temperature varies depending on the oxide semiconductor particles, but is usually 350 ° C. to 600 ° C., and the firing time also varies depending on the oxide semiconductor particles, but is usually 1 to 5 hours.

<Sealing material fixing process>
Next, an annular first sealing material 41A for forming the first sealing portion 41 is prepared. As the first sealing material 41A, a material containing the above-described sealing material is used. The annular first sealing material 41A is obtained by forming an opening in the film after obtaining the film by melting and kneading the sealing material described above and the oxygen-absorbing particles 40a used as necessary. be able to.

  Next, as shown in FIG. 3, the first sealing material 41 </ b> A is fixed on the electrode substrate 10. In order to fix the annular first sealing material 41A on the electrode substrate 10, the annular first sealing material 41A is disposed on the electrode substrate 10, and the annular first sealing material 41A is melted by heating. What is necessary is just to adhere to the electrode substrate 10. Thus, a structure A1 in which the oxide semiconductor layer 30 and the first sealing material 41A are fixed on the electrode substrate 10 is obtained.

  On the other hand, an annular second sealing material 42A for forming the second sealing portion 42 is prepared. The second sealing material 42A contains oxygen absorbing particles. The second sealing material 42A can be obtained by melting and kneading the sealing material described above and the oxygen absorbing particles 40a described above to obtain a film, and then forming an opening in the film.

  At this time, the difference (R2−) between the content R2 (volume%) of the oxygen absorbing particles 40a in the second sealing material 42A and the content R1 (volume%) of the oxygen absorbing particles 40a in the first sealing material 41A. R1) is not particularly limited as long as it is larger than 0% by volume, but it is preferably 2% by volume or more. In this case, the adhesiveness of the first sealing material 41A can be improved more than the adhesiveness of the second sealing material 42A. (R2-R1) is more preferably 10% by volume or more. It is particularly preferable that the first sealing material 41A does not contain the oxygen absorbing particles 40a. In this case, the adhesiveness of the first sealing material 41A can be further improved than the adhesiveness of the second sealing material 42A. Therefore, in the obtained photoelectric conversion element 100, the adhesiveness of the sealing part 40 with respect to the electrode substrate 10 and the counter substrate 20 can be further improved.

  Next, as shown in FIG. 4, the second sealing material 42 </ b> A is fixed on the counter substrate 20. In order to fix the annular second sealing material 42A on the counter substrate 20, the annular second sealing material 42A is disposed on the counter substrate 20, and the annular second sealing material 42A is melted by heating. And may be adhered to the counter substrate 20. Thus, a structure B in which the second sealing material 42A is fixed on the counter substrate 20 is obtained.

<Dye adsorption process>
Next, a dye is adsorbed on the oxide semiconductor layer 30 of the structure A1 obtained as described above. In order to adsorb the dye to the oxide semiconductor layer 30, the structure A1 may be immersed in a dye solution containing the dye. However, the dye may be adsorbed on the oxide semiconductor layer 30 by applying a dye solution containing the dye onto the oxide semiconductor layer 30 and then drying the solution. Thus, the structure A2 is obtained.

<Electrolyte placement process>
Next, as shown in FIG. 5, the electrolyte 50 is disposed on the electrode substrate 10 of the structure A2 to obtain the structure A3.

<Lamination process>
Next, as shown in FIG. 6, the structure A3 and the structure B are overlapped, and the electrode substrate 10 and the counter substrate 20 are bonded together via the first sealing material 41A and the second sealing material 42A. Thus, the first sealing material 41A becomes the first sealing portion 41, the second sealing material 42A becomes the second sealing portion 42, and the first sealing portion 41 is interposed between the electrode substrate 10 and the counter substrate 20. And the sealing part 40 comprised by the 2nd sealing part 42 is formed.

  The electrode substrate 10 and the counter substrate 20 may be bonded together by applying pressure while heating the first sealing material 41A and the second sealing material 42A.

  As described above, the photoelectric conversion element 100 including one photoelectric conversion cell 60 is obtained.

  According to the said manufacturing method, in the photoelectric conversion element 100 obtained, the sealing part 40 contains the oxygen absorption particle 40a. That is, the oxygen absorbing particles 40 a are present in the sealing portion 40. For this reason, in the obtained photoelectric conversion element 100, oxygen that enters from the outside of the sealing portion 40 is sufficiently absorbed by the oxygen absorbing particles 40a. For this reason, compared with the case where the sealing part 40 does not contain the oxygen absorbing particles 40a, it is sufficient that oxygen penetrates the sealing part 40 from the outside of the sealing part 40 and enters the electrolyte 50. It is suppressed. In the sealing material fixing step, oxygen absorbing particles 40a are included in the form of particles in the first sealing material 41A fixed to the electrode substrate 10 and the second sealing material 42A fixed to the counter substrate 20. ing. For this reason, in the process until the photoelectric conversion element 100 is obtained from the sealing material fixing step, the oxygen absorbing particles 40a are sufficiently suppressed from coming into contact with the outside air. That is, oxygen is sufficiently suppressed from being absorbed by the oxygen absorbing particles 40a in the process from the sealing material fixing step to the photoelectric conversion element 100 being obtained. For this reason, in the obtained photoelectric conversion element 100, it is enough that the time until the oxygen absorption capacity of the oxygen absorbing particles 40a reaches the saturation state is sufficiently secured, and the power generation performance of the photoelectric conversion element 100 starts to deteriorate early. It is suppressed. Therefore, the manufacturing method of the photoelectric conversion element 100 can manufacture the photoelectric conversion element 100 having excellent durability.

  Moreover, according to the said manufacturing method, the 1st sealing material 41A with a small content rate of the oxygen absorption particle 40a among the 1st sealing material 41A and the 2nd sealing material 42A contains oxygen absorption particle 40a. Compared to the second sealing material 42 </ b> A having a high rate, the electrode substrate 10 or the counter substrate 20 has better adhesiveness. Therefore, the content R1 of the oxygen absorbing particles 40a in the first sealing material 41A is as large as the content R2 of the oxygen absorbing particles 40a in the second sealing material 42A, and R1 and R2 are the same. In comparison, in the obtained photoelectric conversion element 100, the sealing portion 40 has more excellent adhesion to the electrode substrate 10 and the counter substrate 20. Therefore, the photoelectric conversion element 100 obtained by the manufacturing method can have more excellent durability.

  Furthermore, according to the manufacturing method, in the sealing material fixing step, the first sealing material 41A having a smaller content of oxygen absorbing particles 40a is fixed on the electrode substrate 10 on which the oxide semiconductor layer 30 is formed. Is done. In the dye adsorption step, when the structure A is immersed in the dye solution, the oxide semiconductor layer 30 and the first sealing material 41A come into contact with the dye solution and the dye is adsorbed to the oxide semiconductor layer 30. . At this time, the content rate R1 of the oxygen absorbing particles 40a in the first sealing material 41A is smaller than the content rate R2 of the oxygen absorbing particles 40a in the second sealing material 42A. For this reason, even if the 1st sealing material 41A contacts with a pigment | dye solution, there is little quantity of the pigment | dye adsorb | sucked by the oxygen absorption particle 40a in 41 A of 1st sealing materials. On the other hand, since the second sealing material 42A does not come into contact with the dye solution, the dye does not adsorb to the oxygen absorbing particles 40a in the second sealing material 42A, and sufficient oxygen absorbing ability is secured in the oxygen absorbing particles 40a. Is done. Therefore, in the obtained photoelectric conversion element 100, the time until the oxygen absorption capacity of the oxygen absorbing particles 40a in the sealing portion 40 reaches a saturated state is extended, and the power generation performance of the photoelectric conversion element 100 may begin to deteriorate early. Sufficiently suppressed. Therefore, the said manufacturing method can manufacture the photoelectric conversion element 100 which has more outstanding durability.

  In particular, when the content R1 of the oxygen absorbing particles 40a in the first sealing material 41A is 0% by volume, even if the first sealing material 41A comes into contact with the dye solution in the dye adsorption step, the first sealing is performed. There is no dye adsorbed to the oxygen absorbing particles 40a in the material 41A. For this reason, according to the said manufacturing method, it becomes possible to manufacture the photoelectric conversion element 100 which has much more durable.

Second Embodiment
Next, 2nd Embodiment of the manufacturing method of the photoelectric conversion element which concerns on this invention is described, referring FIGS. 7-10, the same code | symbol is attached | subjected about the component same or equivalent to 1st Embodiment, and the overlapping description is abbreviate | omitted.

  First, prior to the description of the second embodiment of the method for manufacturing a photoelectric conversion element according to the present invention, the photoelectric conversion element manufactured by the second embodiment of the method for manufacturing a photoelectric conversion element of the present invention will be described with reference to FIG. To do. FIG. 7: is sectional drawing which shows the photoelectric conversion element obtained by 2nd Embodiment of the manufacturing method of the photoelectric conversion element which concerns on this invention.

  As shown in FIG. 7, the photoelectric conversion element 200 is the first embodiment in that a sealing portion 240 that constitutes a photoelectric conversion cell 260 is used instead of the sealing portion 40 that constitutes the photoelectric conversion cell 60. This is different from the photoelectric conversion element 100 of FIG. Here, the sealing part 240 has the same configuration as the second sealing part 42 of the first embodiment except that the electrode substrate 10 and the counter substrate 20 are joined.

  Next, a method for manufacturing the photoelectric conversion element 200 will be described with reference to FIGS. 8 to 10 are cross-sectional end views showing a series of steps of the method for manufacturing the photoelectric conversion element 200. FIG.

<Preparation process>
First, the electrode substrate 10 and the counter substrate 20 are prepared.

<Oxide semiconductor layer formation process>
Next, the oxide semiconductor layer 30 is formed over the electrode substrate 10 (see FIG. 2).

<Sealing material fixing process>
Next, an annular sealing material 240A for forming the second sealing portion 240 is prepared. The sealing material 240A has the same configuration as the second sealing material 42A of the first embodiment. For this reason, the sealing material 240A contains oxygen-absorbing particles. The sealing material 240A can be obtained by melting and kneading the sealing material described above and the oxygen absorbing particles 40a described above to obtain a film, and then forming an opening in the film.

  Next, as shown in FIG. 8, the sealing material 240 </ b> A is fixed on the electrode substrate 10. In order to fix the annular sealing material 240A on the transparent conductive layer 12 of the electrode substrate 10, the annular sealing material 240A is disposed on the transparent conductive layer 12 of the electrode substrate 10, and the annular sealing material 240A is heated. And may be melted and adhered to the electrode substrate 10. Thus, a structure A21 in which the oxide semiconductor layer 30 and the sealing material 240A are fixed over the electrode substrate 10 is obtained.

<Dye adsorption process>
Next, a dye is adsorbed on the oxide semiconductor layer 30 of the structure A21 obtained as described above. In order to adsorb the dye to the oxide semiconductor layer 30, the structure A21 may be immersed in a dye solution containing the dye. However, the dye may be adsorbed on the oxide semiconductor layer 30 by applying a dye solution containing the dye onto the oxide semiconductor layer 30 and then drying the solution. Thus, the structure A22 is obtained.

<Electrolyte placement process>
Next, as shown in FIG. 9, the electrolyte 50 is disposed on the electrode substrate 10 of the structure A22 to obtain the structure A23.

<Lamination process>
Next, as shown in FIG. 10, the structure A23 and the counter substrate 20 are overlapped, and the electrode substrate 10 and the counter substrate 20 are bonded to each other through a sealing material 240A. Thus, the sealing material 240 </ b> A becomes the sealing portion 240, and the sealing portion 240 is formed between the electrode substrate 10 and the counter substrate 20.

  Bonding of the electrode substrate 10 and the counter substrate 20 may be performed by applying pressure while heating the sealing material 240A.

  As described above, the photoelectric conversion element 200 including one photoelectric conversion cell 260 is obtained.

  Also by the said manufacturing method, in the photoelectric conversion element 200 obtained, the sealing part 240 contains the oxygen absorption particle 40a. That is, the oxygen absorbing particles 40a are present in the sealing portion 240. For this reason, in the obtained photoelectric conversion element 200, oxygen that enters from the outside of the sealing portion 240 is sufficiently absorbed by the oxygen absorbing particles 40a. For this reason, compared with the case where the sealing part 240 does not contain the oxygen absorbing particles 40a, it is sufficient that oxygen penetrates the sealing part 240 from the outside of the sealing part 240 and enters the electrolyte 50. It is suppressed. In the sealing material fixing step, the oxygen absorbing particles 40a are included in the form of particles in the sealing material 240A fixed to the electrode substrate 10. For this reason, in the process from a sealing material fixing process to the photoelectric conversion element 200 being obtained, it is fully suppressed that the oxygen absorption particle 40a touches external air. That is, in the process from the sealing material fixing step to the photoelectric conversion element 200 being obtained, oxygen is sufficiently suppressed from being absorbed by the oxygen absorbing particles 40a. For this reason, in the obtained photoelectric conversion element 200, it is sufficient that the time until the oxygen absorption capacity of the oxygen absorbing particles 40a reaches the saturation state is sufficiently secured, and the power generation performance of the photoelectric conversion element 200 starts to deteriorate at an early stage. It is suppressed. Therefore, according to the method for manufacturing the photoelectric conversion element 200, the photoelectric conversion element 200 having excellent durability can be manufactured.

  The present invention is not limited to the above embodiment. For example, in the first embodiment, in the sealing material fixing step, the second sealing material 42A is fixed to the counter substrate 20, and the first sealing material 41A is fixed to the electrode substrate 10. The first sealing material 41 </ b> A may be fixed to the counter substrate 20, and the second sealing material 42 </ b> A may be fixed to the electrode substrate 10.

  Further, in the second embodiment, the sealing material 240A is fixed to the electrode substrate 10 in the sealing material fixing step, but the sealing material 240A may be fixed to the counter substrate 20.

  Furthermore, the photoelectric conversion element 200 shown in FIG. 7 may be manufactured by the manufacturing method of the first embodiment. In this case, in the dye adsorption step, the first sealing material 41A fixed to the electrode substrate 10 touches the dye solution, but the second sealing material 42A fixed to the counter substrate 20 does not touch the dye solution. For this reason, durability of the photoelectric conversion element 200 improves compared with the case where the photoelectric conversion element 200 is manufactured with the manufacturing method of 2nd Embodiment.

  Moreover, although the photoelectric conversion elements 100 and 200 obtained by the said embodiment are comprised by one photoelectric conversion cell, the photoelectric conversion elements 100 and 200 may be provided with two or more photoelectric conversion cells. Here, the plurality of photoelectric conversion cells may be connected in series or may be connected in parallel.

  Further, in the above embodiment, the oxide semiconductor layer 30 is provided on the electrode substrate 10 and the photoelectric conversion elements 100 and 200 have a structure in which light is received from the electrode substrate 10 side. In the case of using a laminate (transparent material) in which a transparent conductive layer made of a conductive oxide such as ITO or FTO is used as an electrode on the transparent substrate 11 as the conductive substrate 21 to be used, the oxide semiconductor layer 30 is provided. Instead of the transparent substrate 11, an opaque material (for example, a metal substrate) may be used as a base material, and light receiving may be performed from the counter substrate 20 side. Furthermore, when using the laminated body (transparent material) which formed the transparent conductive layer which consists of conductive oxides, such as ITO and FTO, as the electrode in the transparent substrate 11 as the conductive substrate 21 which comprises the opposing substrate 20, The photoelectric conversion elements 100 and 200 have a structure in which light is received from both the electrode substrate 10 and the counter substrate 20.

  In the above embodiment, the oxide semiconductor layer 30 is formed on the transparent conductive layer 12 in the oxide semiconductor layer forming step. However, the oxide semiconductor layer 30 is formed on the conductive substrate 21 of the counter substrate 20. May be. However, in this case, the catalyst layer 22 is provided on the transparent conductive layer 12.

  Furthermore, in the said embodiment, although the opposing board | substrate 20 is comprised with the electroconductive board | substrate 21 and the catalyst layer 22, the opposing board | substrate 20 may be comprised with an insulating substrate. As the insulating substrate, for example, a glass substrate or a resin film can be used. However, in this case, it is necessary to perform a step of forming a counter electrode after forming the porous insulating layer on the oxide semiconductor layer 30 after the oxide semiconductor layer forming step. Here, the counter electrode can be the same as the counter substrate 20. Alternatively, the counter electrode may be composed of a single porous layer containing, for example, carbon. The porous insulating layer is mainly for impregnating the electrolyte 40 inside. As such a porous insulating layer, for example, an oxide fired body can be used. Note that the porous insulating layer may be formed between the electrode substrate 10 and the counter electrode so as to surround the oxide semiconductor layer 30.

  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, an oxide semiconductor layer was formed on an electrode substrate (trade name “TECa7”, manufactured by Pilkington) on which a transparent conductive layer made of FTO was formed on glass. As the oxide semiconductor layer, an oxide semiconductor layer forming paste (trade name “PST-21NR”, manufactured by JGC Catalysts & Chemicals Co., Ltd.) is prepared, and this paste is baked on the transparent conductive layer of the electrode substrate by screen printing. After printing to a thickness of 9 μm and drying, it was formed by baking at 500 ° C. for 30 minutes.

  Next, an annular first sealing material was prepared. As the first sealing material, a film having a size of 56 mm × 56 mm × 50 μm made of maleic anhydride-modified polyethylene resin (trade name “Binnel 4164”, manufactured by DuPont) is prepared, and 54 mm × 54 mm is provided at the center of the film. It was prepared by forming one opening having the following dimensions. And this cyclic | annular 1st sealing material was arrange | positioned so that an oxide semiconductor layer might be surrounded on an electrode substrate. The first sealing material was bonded to the electrode substrate by heating and melting at 200 ° C. for 0.5 minutes. Thus, a structure A1 in which the oxide semiconductor layer and the first sealing material were fixed on the electrode substrate was obtained.

  On the other hand, a counter electrode as a counter substrate was prepared by forming a catalyst layer made of platinum having a thickness of 10 nm on a titanium foil having a thickness of 40 μm by a sputtering method. At this time, on the surface of the titanium foil, masking was performed so that the catalyst layer was not formed on the peripheral portion where the sealing portion was to be formed.

  Moreover, the cyclic | annular 2nd sealing material was prepared. The second sealing material is a 56 mm × 56 mm obtained by kneading oxygen absorbing particles (made by Mitsui Kinzoku Co., Ltd.) made of a cerium-based oxygen absorbent into maleic anhydride-modified polyethylene resin (trade name “Binell 4164”, manufactured by DuPont). A film having a size of × 50 μm was prepared, and this film was prepared by forming one opening having a size of 54 mm × 54 mm. At this time, the film was formed so that the content of oxygen-absorbing particles was 50% by volume.

  And the cyclic | annular 2nd sealing material was arrange | positioned in the peripheral part in which the catalyst layer was not formed into a film among the titanium foil of a counter substrate. And this 2nd sealing material was adhere | attached on the opposing board | substrate by heating and melting for 3 minutes at 150 degreeC. Thus, a structure B in which the second sealing material was fixed on the counter substrate was obtained.

  Next, the structure A1 was immersed in a dye solution for 16 hours to adsorb the dye to the oxide semiconductor layer, thereby obtaining a structure A2. At this time, a 0.2 mM Z907 dye solution was used as the dye solution.

  Next, an electrolyte was dropped on the oxide semiconductor layer of the structure A2 to obtain a structure A3. At this time, an electrolyte in which iodine was dissolved to 0.01 M in a solvent composed of methoxypropionitrile was used.

  Then, in a vacuum chamber with a vacuum degree of 600 Pa, the surface of the protrusion is formed using a stepped thermal mold in which the structure B is overlaid on the structure A3 and an annular protrusion is provided on the plate-like main body. The electrode substrate and the counter substrate were bonded to each other by heating and melting the first sealing material and the second sealing material while applying a pressure at a temperature of 200 ° C. At this time, pressurization was performed with a press thrust of about 1 kN. Moreover, the thickness of the sealing part became 50 micrometers.

  As described above, a photoelectric conversion element composed of one photoelectric conversion cell was obtained.

(Example 2)
The first sealing material is formed of the same material as the second sealing material, and the first sealing material is fixed to the electrode substrate, whereby oxygen is absorbed in both the first sealing material and the second sealing material. A photoelectric conversion element was obtained in the same manner as in Example 1 except that particles were contained.

(Example 3)
Example 1 except that the first sealing material is fixed instead of fixing the second sealing material to the counter substrate, and the second sealing material is fixed to the electrode substrate instead of fixing the first sealing material. A photoelectric conversion element was obtained in the same manner.

(Comparative Example 1)
By forming the second sealing material with the same material as the first sealing material and fixing the second sealing material to the counter substrate, oxygen is added to both the first sealing material and the second sealing material. A photoelectric conversion element was obtained in the same manner as in Example 1 except that the absorbent particles were not contained.

<Power generation performance>
With respect to the photoelectric conversion elements of Examples 1 to 3 and Comparative Example 1 obtained as described above, an IV curve was measured in a state of being irradiated with white light of 200 lux immediately after production, and the maximum calculated from this IV curve. The output operating power Pm ₀ (μW) was calculated as “output 1”, and this was used as the initial power generation amount. The results are shown in Table 1. The light source, illuminance meter, and power source used for measuring the IV curve are as follows.

Light source: White LED (product name “LEL-SL5N-F”, manufactured by Toshiba Lighting & Technology Corp.)
Illuminance meter: Product name “Digital Illuminance Meter 51013”, Yokogawa Meter & Instruments Power Supply: Voltage / Current Generator (Product name “R6246I”, ADVANTEST)

<Durability>
The photoelectric conversion elements of Examples 1 to 3 and Comparative Example 1 were irradiated with 200 lux of white light for 2500 hours immediately after fabrication. At this time, every time 500 hours elapse, IV curves are measured for the photoelectric conversion elements of Examples 1 to 3 and Comparative Example 1, and the maximum output operating power PW (μW) for each time calculated from this IV curve is expressed as “ Calculated as “Output 2”. And the output maintenance factor was computed based on the following formula. The results are shown in Table 1.

Output maintenance rate = Output 2 / Output 1 x 100 (%)

  As shown in Table 1, all of the photoelectric conversion elements of Examples 1 to 3 did not start decreasing the output retention rate even after 1000 hours, whereas the photoelectric conversion element of Comparative Example 1 was 500 hours. It was found that the output maintenance ratio began to decrease when the time elapsed. And even if 2500 hours passed, the photoelectric conversion elements of Examples 1 to 3 showed an output maintenance ratio of 90% or more, whereas the photoelectric conversion element of Comparative Example 1 had an output maintenance ratio of 79%. It had dropped to.

  From the above results, it was confirmed that according to the method for producing a photoelectric conversion element of the present invention, a photoelectric conversion element having excellent durability can be produced.

DESCRIPTION OF SYMBOLS 10 ... Electrode substrate 20 ... Counter substrate 30 ... Oxide semiconductor layer 40,240 ... Sealing part 40a ... Oxygen absorption particle 41A ... 1st sealing material 42A ... 2nd sealing material 240A ... 2nd sealing material 50 ... Electrolyte 60, 260 ... Photoelectric conversion cell 100, 200 ... Photoelectric conversion element

Claims (4)

An electrode substrate; a counter substrate facing the electrode substrate; an oxide semiconductor layer provided on the electrode substrate or the counter substrate; a dye adsorbed on the oxide semiconductor layer; the electrode substrate and the counter substrate And an annular sealing portion that surrounds the oxide semiconductor layer, and an electrolyte disposed in a cell space formed by the electrode substrate, the counter substrate, and the sealing portion, and the sealing A method for producing a photoelectric conversion element, wherein a part produces a photoelectric conversion element containing oxygen-absorbing particles,
An oxide semiconductor layer forming step of forming the oxide semiconductor layer on the electrode substrate or the counter substrate;
A sealing material fixing step of fixing an annular sealing material forming the sealing portion on at least one of the electrode substrate and the counter substrate;
A dye adsorption step for adsorbing the dye to the oxide semiconductor layer;
An electrolyte disposing step of disposing the electrolyte on the electrode substrate or the counter substrate;
A bonding step of bonding the electrode substrate and the counter substrate through the sealing material,
The method for manufacturing a photoelectric conversion element, wherein the sealing material fixed to at least one of the electrode substrate and the counter substrate includes oxygen-absorbing particles.   In the sealing material fixing step, the sealing material is fixed to the electrode substrate as a first sealing material, the sealing material is fixed to the counter substrate as a second sealing material, and the first sealing material The manufacturing method of the photoelectric conversion element of Claim 1 from which the content rate (volume%) of the oxygen absorption particle in the inside differs from the content rate (volume%) of the oxygen absorption particle in the said 2nd sealing material. In the oxide semiconductor layer forming step, the oxide semiconductor layer is formed on the electrode substrate,
The sealing material fixing step is performed between the oxide semiconductor layer forming step and the dye adsorption step,
In the dye adsorption step, the dye semiconductor is adsorbed on the oxide semiconductor layer by contacting the electrode substrate on which the oxide semiconductor layer and the first sealing material are formed with a dye solution,
In the sealing material fixing step, the content rate (volume%) of the oxygen-absorbing particles in the first sealing material is higher than the content rate (volume%) of the oxygen-absorbing particles in the second sealing material. The manufacturing method of the photoelectric conversion element of Claim 2 which is small.   The manufacturing method of the photoelectric conversion element of Claim 3 whose content rate of the said oxygen absorption particle in a said 1st sealing material is 0 volume%.

Images