Solar power generation device

Abstract

To provide a solar power generation device 2 which is excellent in durability.SOLUTION: A solar power generation device 2 includes a base 4, a negative electrode 6, a positive electrode 8, a power generation cell 10, a solvent barrier layer 12, and a protective layer 14. The solar power generation device 2 has a light receiving surface 16 and a back surface 18. The power generation cell 10 has a photoelectric conversion layer 20, an electron transport layer 22, and a hole transport layer 24. The protection layer 14 contains polysilazane. The solvent barrier layer 12 contains polydimethylsiloxane.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present specification relates to a photovoltaic power generation device including a power generation cell, and in particular, the present specification discloses an improved protective layer for the power generation cell. [Background technology]

[0002] The solar power generation device has a power generation cell. This power generation cell can convert light energy into electrical energy. When this device generates electricity, electrical energy can be obtained without producing carbon dioxide gas. An example of a solar power generation device is disclosed in JP 2023-143864 A. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2023-143864 Summary of the Invention [Problem to be solved by the invention]

[0004] A typical solar power generation device has a protective layer that covers the power generation cell. The protective layer blocks water vapor. The protective layer contributes to the durability of the solar power generation device. However, the water vapor blocking ability of conventional protective layers is insufficient. The present applicant intends to provide a solar power generation device with excellent durability. [Means for solving the problem]

[0005] The solar power generation device disclosed in this specification has a power generation cell and a protective layer for the power generation cell. This protective layer contains polysilazane represented by chemical formula (II) described below.

[0006] The present specification discloses a method for manufacturing a solar power generation device, A: Applying a polysilazane composition to a power generating cell; and B: Irradiating the polysilazane composition with ultraviolet light in an inert gas atmosphere. This process includes the steps of: [Effects of the Invention]

[0007] This solar power generation device is highly durable. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a part of a solar power generation device according to one embodiment. [Figure 2] FIG. 2 is an enlarged cross-sectional view taken along line II-II in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, preferred embodiments will be described in detail with reference to the drawings as appropriate.

[0010] 1 shows a solar power generation device 2. The solar power generation device 2 is in the form of a sheet. In this embodiment, the solar power generation device 2 is flexible. The solar power generation device 2 can be attached to a curved substrate.

[0011] 2 shows an enlarged cross section of the solar power generation device 2. The solar power generation device 2 has a base 4, an anode 6, a cathode 8, a power generation cell 10, a solvent barrier layer 12, and a protective layer 14. The solar power generation device 2 has a light-receiving surface 16 and a back surface 18.

[0012] The base 4 is plate-shaped. The light-receiving surface 16 described above is the surface of the base 4. The base 4 is transparent. Sunlight incident from the light-receiving surface 16 passes through the base 4 and reaches the power-generating cell 10, which will be described in detail later. An example of a material for the base 4 is glass. Preferred examples of glass include quartz glass and alkali-free glass. The base 4 may be obtained from a synthetic resin that has excellent transparency and water vapor blocking properties. Preferred examples of synthetic resins include polyethylene terephthalate, polyethylene naphthalate, polyethylene, polyimide, polyamide, and polyamideimide. Commercially available synthetic resins can be used for the base 4. The thickness of the base 4 is typically 30 μm or more and 300 μm or less.

[0013] The negative electrode 6 is laminated with the base 4. In this embodiment, the negative electrode 6 is in direct contact with the base 4. The negative electrode 6 is transparent. Sunlight that passes through the base 4 also passes through the negative electrode 6 and reaches the power generation cell 10, which will be described in detail later. The negative electrode 6 is conductive. Preferred materials for the negative electrode 6 include fluorine-doped tin oxide (FTO) and indium tin oxide (ITO). The thickness of the negative electrode 6 is typically 30 nm or more and 300 nm or less.

[0014] The positive electrode 8 is laminated with the base 4. In this embodiment, the positive electrode 8 is in direct contact with the base 4. The positive electrode 8 is conductive. Preferred materials for the positive electrode 8 include fluorine-doped tin oxide (FTO) and indium tin oxide (ITO). The thickness of the positive electrode 8 is typically 30 nm or more and 300 nm or less.

[0015] The power generating cell 10 has a photoelectric conversion layer 20, an electron transport layer 22, and a hole transport layer 24. The photoelectric conversion layer 20, the electron transport layer 22, and the hole transport layer 24 are stacked in this order.

[0016] The photoelectric conversion layer 20 generates electrons and holes by photoexcitation. In other words, the photoelectric conversion layer 20 can convert solar energy into electrical energy. A preferred photoelectric conversion layer 20 contains a perovskite compound. A perovskite compound represented by the following chemical formula (I) is preferred. RM-X3(I) This perovskite compound has a perovskite-type crystal structure. A solar power generation device 2 including this perovskite compound is called an "organic-inorganic hybrid type."

[0017] In this chemical formula (I), R is an organic molecule. Preferred examples of the organic molecule include alkylammonium derivatives and formamidinium derivatives.

[0018] In the above chemical formula (I), M is a metal atom. Preferred examples of the metal atom include copper, nickel, manganese, iron, cobalt, palladium, germanium, tin, lead, and eurobium.

[0019] In the above chemical formula (I), X is a halogen atom or a chalcogen atom. Preferred halogen atoms include fluorine, chlorine, bromine, and iodine. Preferred chalcogen atoms include sulfur and selenium atoms.

[0020] A preferred lattice of the perovskite compound has a metal atom M at the body center, an organic molecule R at each vertex, and a halogen atom or chalcogen atom at the face center.

[0021] The photoelectric conversion layer 20 may contain other substances in addition to the perovskite compound. The thickness of the photoelectric conversion layer 20 is typically 1 nm or more and 100 nm or less.

[0022] The electron transport layer 22 is located between the anode 6 and the photoelectric conversion layer 20. In this embodiment, the electron transport layer 22 is in direct contact with the anode 6 and also in direct contact with the photoelectric conversion layer 20. The electron transport layer 22 transports electrons generated in the photoelectric conversion layer 20 to the anode 6. A preferred material for the electron transport layer 22 is a metal oxide. Preferred examples of metal oxides include tin oxide, titanium oxide, molybdenum oxide, vanadium oxide, zinc oxide, nickel oxide, lithium oxide, potassium oxide, cesium oxide, aluminum oxide, niobium oxide, and barium oxide. Tin oxide is preferred. The material for the electron transport layer 22 may be a halogen compound. The thickness of the electron transport layer 22 is typically 1 nm or more and 100 nm or less.

[0023] The hole transport layer 24 connects the photoelectric conversion layer 20 and the positive electrode 8. In this embodiment, the hole transport layer 24 is in direct contact with the positive electrode 8 and also with the photoelectric conversion layer 20. The hole transport layer 24 transports holes generated in the photoelectric conversion layer 20 to the positive electrode 8. Preferred materials for the hole transport layer 24 include carbon-based materials and spiro-based materials. From the viewpoint of cost, a hole transport layer 24 mainly composed of carbon is preferred. From the viewpoint of power generation efficiency, a carbon-based material containing a sensitizer is preferred. Examples of preferred sensitizers include lithium bis(trifluoromethane)sulfonimide and 4-tert-butylpyridine. Two or more sensitizers may be used in combination. The thickness of the hole transport layer 24 is typically 1 μm or more and 300 μm or less. Preferably, this thickness is 14.3 μm or more and 143 μm or less.

[0024] Because the cost of the hole transport layer 24, which is mainly composed of carbon, is low, the cost of the solar power generation device 2 is not excessively high even if an expensive perovskite compound is used in the photoelectric conversion layer 20. From the viewpoint of cost, it is preferable that the main component of the hole transport layer 24 is carbon and that the main component of the positive electrode 8 is also carbon. The hole transport layer 24 and the positive electrode 8 may be integrated.

[0025] The hole transport layer 24, which is mainly composed of carbon, can be formed through a coating process. This process can contribute to reducing the cost of the solar power generation device 2. From the viewpoint of cost reduction, it is preferable that the hole transport layer 24 and the positive electrode 8 are integrally formed through a coating process.

[0026] The solvent barrier layer 12 covers the power generating cell 10. In this embodiment, the solvent barrier layer 12 is in direct contact with the hole transport layer 24. As will be described later, the protective layer 14 is formed by coating a composition containing a solvent. A typical solvent is dibutyl ether. If this solvent comes into contact with the power generating cell 10, it may damage the photoelectric conversion layer 20. The solvent barrier layer 12 prevents this solvent from coming into contact with the power generating cell 10. In the manufacture of a solar power generating device 2 having the solvent barrier layer 12, there is a high degree of freedom in the selection of a solvent for the protective layer 14. In this manufacture, a solvent suitable for the protective layer 14 can be selected.

[0027] Preferably, the main component of the solvent barrier layer 12 is polydimethylsiloxane. Polydimethylsiloxane is liquid. Therefore, polydimethylsiloxane can be applied to the power-generating cell 10 without being mixed with a solvent. The solvent barrier layer 12 can be formed by curing this polydimethylsiloxane with light or heat. The solvent barrier layer 12, whose main component is polydimethylsiloxane, can be easily formed. The thickness of the solvent barrier layer 12 is typically 1 μm or more and 10 μm or less.

[0028] The solvent barrier layer 12 is not an essential element. A solar power generation device 2 in which the photoelectric conversion layer 20 is not damaged by the solvent in the protective layer 14 does not need to have the solvent barrier layer 12.

[0029] The protective layer 14 is laminated on the solvent barrier layer 12. In this embodiment, the protective layer 14 is in direct contact with the solvent barrier layer 12. In the case of a solar power generation device 2 that does not have the solvent barrier layer 12, the protective layer 14 may be in direct contact with the power generation cell 10. In this embodiment, the protective layer 14 is exposed on the back surface 18. The protective layer 14 can prevent water vapor from reaching the photoelectric conversion layer 20. A solar power generation device 2 that has this protective layer 14 has excellent durability.

[0030] The protective layer 14 contains polysilazane. Polysilazane has excellent water vapor blocking properties. It is preferable that the main component of the protective layer 14 is polysilazane. Specifically, the ratio of polysilazane in the protective layer 14 is preferably 50 mass % or more, more preferably 80 mass % or more, and particularly preferably 90 mass % or more. This ratio may be 100 mass %. From the viewpoint of water vapor blocking properties, polysilazane represented by the following chemical formula (II) is preferable. This polysilazane is derived from perhydropolysilazane, as described later.

[0031] [ka]

[0032] In this chemical formula (II), n is a natural number.

[0033] 2, the arrow Tp indicates the thickness of the protective layer 14. From the viewpoint of water vapor blocking properties, the thickness Tp is preferably 0.7 μm or more, more preferably 1.0 μm or more, and particularly preferably 1.4 μm or more. From the viewpoint of flexibility of the solar power generation device 2, the thickness Tp is preferably 10.0 μm or less.

[0034] This solar power generation device 2 is grounded to a substrate with the light-receiving surface 16 generally facing upward. Sunlight incident on the light-receiving surface 16 passes through the base 4, the negative electrode 6, and the electron transport layer 22, and reaches the photoelectric conversion layer 20. The photoelectric conversion layer 20 receives the sunlight and generates holes and electrons. The electrons reach the negative electrode 6 via the electron transport layer 22. The holes reach the positive electrode 8 via the hole transport layer 24. This solar power generation device 2 converts solar energy into electrical energy.

[0035] The following describes an example of a method for manufacturing the solar power generation device 2. This manufacturing method includes the following steps (1) to (3). (1) A solvent barrier composition is applied to the power generating cell 10 to form a solvent barrier layer 12. (2) Applying a polysilazane composition to the solvent barrier layer 12. (3) Irradiating the polysilazane composition with ultraviolet light in an inert gas atmosphere.

[0036] Preferably, in step (1), a solvent barrier composition containing polydimethylsiloxane as a main component is applied to the power-generating cell 10. Because this composition does not contain a solvent, this composition is less likely to damage the power-generating cell 10. If the polysilazane composition described below does not contain a solvent that would damage the power-generating cell 10, this step (1) may be omitted.

[0037] Preferably, in step (2), a polysilazane composition containing dibutyl ether is applied to the solvent barrier layer 12. Preferably, in step (2), a composition containing perhydropolysilazane is applied to the power-generating cell 10. The molecule of perhydropolysilazane is represented by the following chemical formula (III).

[0038] [ka]

[0039] In this chemical formula (III), m is a natural number.

[0040] In step (3), polysilazane molecules in the polysilazane composition irradiated with ultraviolet light undergo a chemical reaction. This chemical reaction produces a polysilazane with a dense molecular structure and therefore excellent water vapor blocking properties. When perhydropolysilazane is irradiated with ultraviolet light in an inert gas atmosphere, polysilazane represented by chemical formula (II) is obtained. Preferably, ultraviolet light is irradiated in a nitrogen gas atmosphere. The preferred ultraviolet light is excimer light.

[0041] [Disclosure items] Each of the following sections discloses a preferred embodiment.

[0042] [Item 1] The fuel cell includes a power generating cell and a protective layer for the power generating cell, The photovoltaic power generation device, wherein the protective layer contains polysilazane represented by the following chemical formula (II): [ka] (In this chemical formula (II), n is a natural number.)

[0043] [Item 2] Item 10. The solar power generation device according to item 1, further comprising a solvent barrier layer positioned between the power generation cell and the protective layer.

[0044] [Item 3] 3. The solar power generation device according to item 2, wherein the main component of the solvent barrier layer is polydimethylsiloxane.

[0045] [Item 4] a light receiving surface and a back surface, 4. The solar power generation device according to any one of items 1 to 3, wherein at least a portion of the protective layer is exposed on the back surface.

[0046] [Item 5] 5. The photovoltaic power generation device according to any one of items 1 to 4, wherein the protective layer has a thickness of 0.7 μm or more.

[0047] [Item 6] 6. The solar power generation device according to any one of items 1 to 5, wherein the power generation cell has a photoelectric conversion layer that generates holes by photoexcitation, and a hole transport layer in contact with the photoelectric conversion layer.

[0048] [Item 7] 7. The solar power generation device according to item 6, wherein the photoelectric conversion layer contains a perovskite compound.

[0049] The durability of power-generating cells containing perovskite compounds is insufficient. In the solar power-generating device according to item 7, the protective layer protects the power-generating cells. This solar power-generating device has excellent durability. This solar power-generating device is suitable for industrial production.

[0050] [Item 8] 8. The solar-power generating device according to item 6 or 7, wherein the main component of the hole transport layer is carbon.

[0051] [Item 9] Item 9. The photovoltaic device of item 8, wherein the hole transport layer comprises a sensitizer.

[0052] [Item 10] 10. The photovoltaic power generating device according to item 9, wherein the sensitizer is lithium bis(trifluoromethane)sulfonimide and / or 4-tert-butylpyridine.

[0053] [Item 11] 11. The solar power generation device according to any one of items 6 to 10, wherein the thickness of the hole transport layer is 14.3 μm or more and 143 μm or less.

[0054] [Item 12] A: Applying a polysilazane composition to a power generating cell; and B: Irradiating the polysilazane composition with ultraviolet light in an inert gas atmosphere. A method for manufacturing a solar power generation device, comprising the steps of:

[0055] In the manufacturing method according to item 12, oxidation of polysilazane is suppressed. In this manufacturing method, step B can be performed in a short time. This manufacturing method can provide a dense protective layer. This protective layer sufficiently blocks water vapor.

[0056] [Item 13] Item 13. The manufacturing method according to Item 12, wherein in step A, the polysilazane composition containing perhydropolysilazane is applied to the power-generating cell.

[0057] [Item 14] Item 14. The method according to item 12 or 13, wherein in step B, the polysilazane composition is irradiated with excimer light.

[0058] [Item 15] (1) Applying a solvent barrier composition to a power generation cell to form a solvent barrier layer. (2) applying a polysilazane composition to the solvent barrier layer; and (3) Irradiating the polysilazane composition with ultraviolet light in an inert gas atmosphere. A method for manufacturing a solar power generation device, comprising the steps of:

[0059] [Item 16] Item 16. The manufacturing method according to item 15, wherein in step (1), a solvent barrier composition containing polydimethylsiloxane as a main component is applied.

[0060] [Item 17] Item 17. The method according to item 15 or 16, wherein in step (2), the polysilazane composition containing perhydropolysilazane is applied to the solvent barrier layer.

[0061] [Item 18] 18. The method according to any one of items 15 to 17, wherein in step (2), the polysilazane composition containing dibutyl ether is applied to the solvent barrier layer.

[0062] [Item 19] 19. The method according to any one of items 15 to 18, wherein in the step (3), the polysilazane composition is irradiated with excimer light. [Industrial Applicability]

[0063] The solar power generation device described above can be attached to various structures such as the roof of a building, the roof of an automobile, a utility pole, or a bridge pier. [Explanation of symbols]

[0064] 2. Solar power generation equipment 4. Base 6...Negative electrode 8...Positive electrode 10. Power generation cell 12. Solvent Barrier Layer 14...Protective layer 16... Light receiving surface 18...Back 20. Photoelectric conversion layer 22...electron transport layer 24...Hole transport layer

Claims

1. The fuel cell includes a power generating cell and a protective layer for the power generating cell, The photovoltaic power generation device, wherein the protective layer contains polysilazane represented by the following chemical formula (II): 【Chemistry 4】 (In this chemical formula (II), n is a natural number.)

2. The solar power generation device according to claim 1 , further comprising a solvent barrier layer positioned between the power generation cell and the protective layer.

3. The solar power generation device according to claim 2 , wherein the main component of the solvent barrier layer is polydimethylsiloxane.

4. a light receiving surface and a back surface, The solar power generation device according to claim 1 or 2, wherein at least a portion of the protective layer is exposed on the back surface.

5. 3. The solar power generation device according to claim 1, wherein the protective layer has a thickness of 0.7 [mu]m or more.

6. 3. The solar power generation device according to claim 1, wherein the power generation cell comprises a photoelectric conversion layer that generates holes by photoexcitation, and a hole transport layer in contact with the photoelectric conversion layer.

7. The solar power generation device according to claim 6 , wherein the photoelectric conversion layer contains a perovskite compound.

8. 7. The solar power generating device according to claim 6, wherein the hole transport layer is mainly composed of carbon.

9. The photovoltaic device of claim 8 , wherein the hole transport layer comprises a sensitizer.

10. 10. The solar power generation device according to claim 9, wherein the sensitizer is lithium bis(trifluoromethane)sulfonimide and / or 4-tert-butylpyridine.

11. 7. The solar power generation device according to claim 6, wherein the hole transport layer has a thickness of 14.3 μm or more and 143 μm or less.

12. A: Applying a polysilazane composition to a power generating cell; and B: Irradiating the polysilazane composition with ultraviolet light in an inert gas atmosphere. A method for manufacturing a solar power generation device, comprising the steps of:

13. The manufacturing method according to claim 12 , wherein in the step A, the polysilazane composition containing perhydropolysilazane is applied to the power-generating cell.

14. The method according to claim 12 or 13, wherein in the step B, the polysilazane composition is irradiated with excimer light.

15. (1) Applying a solvent barrier composition to a power generation cell to form a solvent barrier layer (2) Applying a polysilazane composition to the solvent barrier layer. and (3) Irradiating the polysilazane composition with ultraviolet light in an inert gas atmosphere. A method for manufacturing a solar power generation device, comprising the steps of:

16. The manufacturing method according to claim 15, wherein in step (1), a solvent barrier composition containing polydimethylsiloxane as a main component is applied.

17. The method according to claim 15 or 16, wherein in the step (2), the polysilazane composition containing perhydropolysilazane is applied to the solvent barrier layer.

18. 17. The method according to claim 15, wherein in the step (2), the polysilazane composition containing dibutyl ether is applied to the solvent barrier layer.

19. 17. The method according to claim 15, wherein in the step (3), the polysilazane composition is irradiated with excimer light.

Images