Perovskite solar cell manufacturing method and manufacturing device

Abstract

To provide a manufacturing method and a manufacturing device for a perovskite solar cell with improved film quality of a photoelectric conversion layer.SOLUTION: The present invention relates to a method for manufacturing a perovskite solar cell, which includes the steps of applying a precursor solution of a perovskite compound in the form of droplets, and applying a poor solvent in the form of droplets until the droplets of the precursor solution adhering to the application surface combine with droplets of other precursor solutions, and to a device for manufacturing a perovskite solar cell, which includes a precursor solution application unit, a poor solvent application unit, and a control unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for manufacturing a perovskite solar cell. [Background technology]

[0002] Solar cells are widely used as an energy source with low environmental impact. One type of solar cell known is the perovskite solar cell, in which the main component of the photoelectric conversion layer is a perovskite compound.

[0003] As a method for manufacturing a perovskite solar cell, for example, Patent Document 1 describes a method in which a material film for a perovskite thin film is applied, and then a poor solvent in gaseous or mist form is sprayed onto the material film for the perovskite thin film to dry and crystallize the material film for the perovskite thin film. However, the present inventors have found that when a poor solvent is added to the material film for the perovskite thin film, the poor solvent does not mix sufficiently with the material film, resulting in a problem in that the film quality of the photoelectric conversion layer is impaired. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-148126 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, conventional methods for producing perovskite solar cells have had the problem of impairing the film quality of the photoelectric conversion layer containing a perovskite compound. Therefore, an object of the present invention is to provide a method and apparatus for producing perovskite solar cells with improved film quality of the photoelectric conversion layer. [Means for solving the problem]

[0006] The present inventors have discovered that the film quality of a photoelectric conversion layer containing a perovskite compound can be improved by applying droplets of a poor solvent before droplets of a precursor solution of a perovskite compound combine with droplets of other precursor solutions to form a film, and have completed the present invention.

[0007] That is, the gist of the present invention is as follows. (1) applying a precursor solution of a perovskite compound as droplets; a step of applying a poor solvent as droplets until the droplets of the precursor solution attached to the coating surface are combined with other droplets of the precursor solution; A method for producing a perovskite solar cell, comprising: (2) The method for producing a perovskite solar cell according to (1) above, wherein the precursor solution and the poor solvent are applied by an inkjet method or a spray method. (3) The method for producing a perovskite solar cell according to (1) or (2), wherein the poor solvent is at least one solvent selected from solvents having a relative dielectric constant of 20 or less and a boiling point of 100°C or more. (4) The method for producing a perovskite solar cell according to any one of (1) to (3) above, wherein the temperature of the precursor solution is 40°C or higher and the temperature of the coating surface is 60°C or higher. (5) a precursor solution application unit that applies a precursor solution of a perovskite compound as droplets; a poor solvent application unit that applies a poor solvent in the form of droplets; a control unit that controls the precursor solution application unit and the poor solvent application unit so that the poor solvent is applied as droplets before the droplets of the precursor solution attached to the application surface are combined with other droplets of the precursor solution; A manufacturing apparatus for a perovskite solar cell, comprising: [Effects of the Invention]

[0008] The present invention makes it possible to provide a method and apparatus for manufacturing a perovskite solar cell with improved film quality of the photoelectric conversion layer. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram of an embodiment of a manufacturing apparatus of the present invention. [Figure 2] 1 is a photograph showing the appearance of a wet film of Example 1. [Figure 3] 1 is a photograph showing the appearance of a wet film of Comparative Example 1. [Figure 4] 1 is a photograph showing the appearance of a wet film of Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present invention will now be described in detail.

[0011] The present invention relates to a method for producing a perovskite solar cell having a photoelectric conversion layer containing a perovskite compound. The method for producing a solar cell of the present invention includes a step of applying a precursor solution of a perovskite compound in the form of droplets (precursor solution application step) and a step of applying a poor solvent in the form of droplets (poor solvent application step). In the present invention, in the poor solvent application step, the poor solvent is applied in the form of droplets before the droplets of the precursor solution adhering to the application surface combine with droplets of other precursor solutions, thereby obtaining a uniform photoelectric conversion layer and improving the film quality of the photoelectric conversion layer.

[0012] In the precursor solution application step of the manufacturing method of the present invention, a precursor solution of a perovskite compound is applied in the form of droplets. Here, the precursor solution refers to a solution containing a perovskite compound as a solute.

[0013] A perovskite compound is a compound having a perovskite-type crystal structure. The perovskite-type crystal structure typically consists of ions A, B, and X. The perovskite-type crystal structure has a cubic unit cell, with A located at each vertex of the cubic crystal, B located at the body center, and X located at each face center of the cubic crystal centered on A. The fact that a compound has a perovskite-type crystal structure can be confirmed, for example, by X-ray diffraction measurement.

[0014] The perovskite compound can be represented by, for example, the following formula (1). ABX3(1) (wherein A is a monovalent cation, B is a divalent cation, and X is a monovalent anion.)

[0015] In one embodiment, in formula (1), A is at least one selected from the group consisting of a monovalent organic ammonium ion, a monovalent amidinium ion, and a monovalent metal ion. Examples of the monovalent organic ammonium ion include CH3NH3 + (Methylammonium ion: MA), C2H5NH3 + , C3H7NH3 + and C4H9NH3 + Examples of monovalent amidinium ions include HC(NH2)2 + (formamidinium ion: FA). Examples of monovalent metal ions include rubidium ion (Rb + ) and cesium ions (Cs + In formula (1), A may be a combination of a monovalent organic ammonium ion, a monovalent amidinium ion, and a monovalent metal ion. In formula (1), A is preferably MA, FA, or Cs + and combinations of two or three of these. + or Cs + If it contains Rb relative to the total amount of A + or Cs + The content is usually 10 atomic % or less.

[0016] In one embodiment, in formula (1), B is a divalent metal ion, for example, a lead ion (Pb 2+ ), tin ions (Sn 2+ ) and combinations thereof, more preferably Pb 2+ is.

[0017] In one embodiment, in formula (1), X is a halogen ion, for example, a fluoride ion (F - ), chloride ions (Cl -), bromide ion (Br - ) and iodide ion (I - ) and at least one selected from Cl - , Br - and I - is preferred.

[0018] The precursor solution can be prepared by dissolving a perovskite compound, a solvent adduct of a perovskite compound, or multiple raw materials for the perovskite compound in an appropriate solvent. For example, when the perovskite compound is represented by the above formula (1), the precursor solution can be prepared by dissolving one or more compounds represented by the following formula (2) and one or more compounds represented by the following formula (3) in an appropriate solvent. AXE (2) BX2(3)

[0019] As the solvent for the precursor solution, for example, a solvent having a relative dielectric constant of 30 or more can be used. In one embodiment, when the precursor solution is applied by an inkjet method, the solvent for the precursor solution is preferably a solvent having a boiling point of 100°C or higher from the viewpoint of preventing clogging of the inkjet nozzle. The solvent for the precursor solution is not particularly limited, and examples thereof include organic solvents such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP), and γ-butyrolactone (GBL). As the solvent for the precursor solution, these solvents may be used alone or in combination of two or more. In one embodiment, the solvent for the precursor solution is DMF, DMSO, GBL, or a mixture thereof.

[0020] As described above, in the precursor solution application step, the precursor solution of the perovskite compound is applied as droplets to the application surface. In one embodiment, the application surface is the surface of a first carrier transport layer (e.g., a hole transport layer or an electron transport layer) described below for perovskite solar cells. The application of the precursor solution as droplets can be carried out by, for example, spin coating, slit coating, inkjet coating, and spraying, with the inkjet coating and spraying methods being preferred, and the inkjet coating being more preferred.

[0021] The conditions for applying the precursor solution can be appropriately selected from commonly used conditions.

[0022] The precursor solution application step can be carried out in a dry air atmosphere or an inert gas atmosphere. The inert gas is not particularly limited, and examples thereof include nitrogen and argon gases. However, nitrogen gas is preferred from the viewpoints of availability and production costs.

[0023] In the precursor solution application step, the temperature of the precursor solution is usually 25°C or higher, and preferably 40°C or higher. The temperature of the precursor solution is usually 60°C or lower, and preferably 50°C or lower. In the precursor solution application step, the temperature of the application surface is usually 20°C or higher, preferably 40°C or higher, and more preferably 60°C or higher. The temperature of the application surface is usually 80°C or lower, and preferably 70°C or lower. In a preferred embodiment, the temperature of the precursor solution is 40°C or higher, and the temperature of the application surface is 60°C or higher. In this embodiment, high-quality perovskite crystals are produced.

[0024] In the poor solvent application step of the manufacturing method of the present invention, a poor solvent is applied as droplets to the precursor solution droplets adhered to the coating surface before they combine with other precursor solution droplets. Application of the poor solvent can promote the generation of crystal nuclei of the perovskite compound. In the manufacturing method of the present invention, by applying the poor solvent as droplets before the precursor solution droplets adhered to the coating surface combine with other precursor solution droplets and spread to form a film, the precursor solution droplets and the poor solvent droplets are thoroughly mixed. This allows for a photoelectric conversion layer that uniformly contains the perovskite compound and has improved film quality to be obtained, resulting in improved power generation efficiency of the solar cell.

[0025] In the present invention, the term "poor solvent" refers to a solvent in which the solubility of the perovskite compound is lower than that of the solvent of the precursor solution, and more preferably, a solvent in which the perovskite compound is substantially incapable of being dissolved. The term "poor solvent" refers to, for example, a solvent in which the solubility of the perovskite compound at 25°C (weight ratio of solute to 100 g of solvent) is typically less than 1.0 wt%, preferably less than 0.1 wt%, and more preferably less than 0.01 wt%. Examples of poor solvents that can be used include solvents with a relative dielectric constant of 20 or less. Examples of poor solvents include, but are not limited to, substituted aliphatic hydrocarbons such as dichloromethane and chloroform; aromatic compounds such as toluene, benzene, chlorobenzene, and tetralin; ethers such as diethyl ether and tetrahydrofuran (THF); alcohols with 3 or more carbon atoms (e.g., 1-propanol, 2-propanol, and 1-butanol); hydrocarbons with 4 to 10 carbon atoms; and organic solvents such as acetic acid. In the present invention, the term "aromatic compound" also includes compounds containing an aromatic ring in part. The poor solvent may be one of these solvents, or a combination of two or more of them. In one embodiment, when the poor solvent is applied by an inkjet method, the poor solvent is preferably a solvent having a boiling point of 100°C or higher, from the viewpoint of preventing clogging of the inkjet nozzle. In a preferred embodiment, the poor solvent is one or more solvents selected from solvents having a relative dielectric constant of 20 or lower and a boiling point of 100°C or higher. Such poor solvents are not particularly limited, and examples thereof include toluene, chlorobenzene, tetralin, 1-butanol, and acetic acid. In one embodiment, the poor solvent is tetralin or 2-propanol. Furthermore, using a solvent having a relative dielectric constant of 5 or higher and 20 or lower (preferably a solvent having a relative dielectric constant of 10 or higher and 20 or lower) as the poor solvent improves the uniformity of the photoelectric conversion layer.

[0026] In the poor solvent application step, the poor solvent is applied as droplets to the application surface. In one embodiment, the application surface is the surface of a first carrier transport layer (e.g., a hole transport layer or an electron transport layer), as described above for the precursor solution application step. The application of the poor solvent as droplets can be performed by, for example, a spin coating method, an inkjet method, or a spray method, with the inkjet method and the spray method being preferred, and the inkjet method being more preferred. In a preferred embodiment, the precursor solution and the poor solvent are applied by the inkjet method or the spray method, more preferably by the inkjet method.

[0027] The poor solvent coating step can be carried out in a dry air atmosphere or an inert gas atmosphere, similarly to the precursor solution coating step.

[0028] In the poor solvent application step, the temperature of the poor solvent is usually 25°C or higher, and preferably 40°C or higher. The temperature of the poor solvent is usually 60°C or lower, and preferably 50°C or lower. The temperature of the poor solvent is preferably the same as the temperature of the precursor solution. In the poor solvent application step, the temperature of the application surface is, as described above for the precursor solution application step, usually 20°C or higher, preferably 40°C or higher, more preferably 60°C or higher, and usually 80°C or lower, and preferably 70°C or lower. In a preferred embodiment, the temperature of the poor solvent is 40°C or higher, and the temperature of the application surface is 60°C or higher. In this embodiment, high-quality perovskite crystals are produced.

[0029] In the poor solvent application step, the poor solvent is applied as droplets to the precursor solution droplets before the droplets of the precursor solution adhering to the application surface combine with droplets of other precursor solutions. The applied droplets of poor solvent come into contact with and combine with the droplets of the precursor solution. The timing of application of the poor solvent is not particularly limited as long as it occurs before the droplets of the precursor solution combine with droplets of other precursor solutions. The timing of application of the poor solvent may be simultaneous with application of the precursor solution, or may be applied, for example, at an interval of about 0.1 to 1.0 seconds after application of the precursor solution. In the present invention, "until the droplets of the precursor solution combine with droplets of other precursor solutions" refers to the time until the droplets of the precursor solution come into contact with droplets of other precursor solutions. The poor solvent may be applied so that the applied droplets of poor solvent come into contact with the droplets of the precursor solution, or so that the droplets of poor solvent adhering to the application surface spread and come into contact with the droplets of the precursor solution.

[0030] The conditions for applying the poor solvent can be appropriately selected from commonly used conditions, except that the poor solvent is applied as droplets until the droplets of the precursor solution adhering to the application surface combine with droplets of other precursor solutions.

[0031] The manufacturing method of the present invention may include an annealing step after the poor solvent coating step. By carrying out the annealing step, a photoelectric conversion layer is formed.

[0032] The annealing treatment is usually a treatment in which the coating film is heated at a temperature of 70°C or higher and 200°C or lower.

[0033] The production method of the present invention may include a drying step between the poor solvent coating step and the annealing step. In the drying step, the solvent is removed from the coating film using a known drying method such as heating, blowing a dry gas, or vacuuming. When the production method of the present invention does not include a drying step, the annealing step may be understood as a process in which the annealing and drying steps are performed in a single operation.

[0034] The perovskite solar cell obtained by the production method of the present invention (hereinafter also referred to as the solar cell of the present invention) has a photoelectric conversion layer containing a perovskite compound.

[0035] In one embodiment, the solar cell of the present invention has, in this order, a substrate, a first electrode layer, a first carrier transport layer, a photoelectric conversion layer containing a perovskite compound, a second carrier transport layer, and a second electrode layer.

[0036] In one embodiment, the first carrier transport layer is a hole transport layer (HTL) and the second carrier transport layer is an electron transport layer (ETL), and in another embodiment, the first carrier transport layer is an electron transport layer and the second carrier transport layer is a hole transport layer.

[0037] The first electrode layer and the second electrode layer can be an anode or a cathode. In one embodiment, the first electrode layer is an anode, the first carrier transport layer is a hole transport layer, the second electrode layer is a cathode, and the second carrier transport layer is an electron transport layer. In another embodiment, the first electrode layer is a cathode, the first carrier transport layer is an electron transport layer, the second electrode layer is an anode, and the second carrier transport layer is a hole transport layer.

[0038] In a first embodiment of the solar cell of the present invention, the solar cell has a substrate, a first electrode layer, an electron transport layer, a photoelectric conversion layer, a hole transport layer, and a second electrode layer in this order.

[0039] In a second embodiment of the solar cell of the present invention, the solar cell has a substrate, a first electrode layer, a hole transport layer, a photoelectric conversion layer, an electron transport layer, and a second electrode layer in this order.

[0040] The substrate is a plate-like or film-like member. The material of the substrate is not particularly limited, and examples thereof include inorganic materials such as glass, organic materials such as polyethylene, polyethylene terephthalate, polyethylene naphthalate, polyimide, polyamide, polyamideimide, liquid crystal polymer, and cycloolefin polymer, and metal materials such as stainless steel and silicon. The substrate material is preferably glass.

[0041] The substrate may be transparent or opaque. When light is incident from the surface of the substrate, a transparent substrate is used. As the transparent substrate, a substrate made of glass, polyethylene terephthalate, polyethylene naphthalate, polyimide, polyamide, polyamideimide, or cycloolefin polymer can be used. When light is incident from the opposite side of the substrate, the substrate can be opaque. The thickness of the substrate is usually several tens of μm to several mm.

[0042] The first and second electrode layers can be made of metal materials such as aluminum (Al), silver (Ag), and gold (Au), transparent conductive films such as indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), and fluorine-doped tin oxide (FTO), and carbon nanotubes, all of which are known materials for solar cell electrodes. The first and second electrode layers are preferably made of ITO, IZO, or FTO. The thickness of each of the first and second electrode layers is typically 50 nm to 500 nm.

[0043] The hole transport layer transports holes generated by photoelectric conversion in the photoelectric conversion layer to the first electrode layer or the second electrode layer. Known organic or inorganic materials suitable for hole transport layers can be used as the material for the hole transport layer. Examples of organic materials include, but are not limited to, 2,2',7,7'-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD), polyethylenedioxythiophene:polystyrenesulfonic acid (PEDOT:PSS), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), and [2-(3,6-dimethoxy-9H-carbazol-9H-yl)ethyl]phosphonic acid (MeO-2PACz). Examples of inorganic materials include, but are not limited to, nickel oxide, copper oxide, cobalt oxide, and copper iodide. In the first embodiment of the solar cell of the present invention, the material of the hole transport layer is preferably Spiro-OMeTAD, PTAA, and nickel oxide. In the second embodiment of the solar cell of the present invention, the material of the hole transport layer is preferably PEDOT:PSS, PTAA, and nickel oxide. The thickness of the hole transport layer is usually 1 nm to 1000 nm.

[0044] The electron transport layer has a function of transporting electrons generated by photoelectric conversion in the photoelectric conversion layer to the first electrode layer or the second electrode layer. The material of the electron transport layer can be any known organic or inorganic material that can be used for electron transport layers. Examples of organic materials include, but are not limited to, fullerene compounds, phenanthroline derivatives (e.g., bathocuproine), and polyethyleneimines. Examples of fullerene compounds include fullerenes (e.g., C60 fullerene, C70 fullerene), and derivatives of fullerenes with a substituent added (e.g., [6,6]-phenyl-C 61 -methyl butyrate (also known as PCBM or

[60] PCBM), [6,6]-phenyl-C 71Examples of inorganic materials include titanium oxide, tin oxide, and zinc oxide. In the first embodiment of the solar cell of the present invention, the material of the electron transport layer is preferably fullerene, PCBM, bathocuproine, polyethyleneimines, titanium oxide, and tin oxide. In the second embodiment of the solar cell of the present invention, the material of the electron transport layer is preferably fullerene, PCBM, bathocuproine, and polyethyleneimines. The thickness of the electron transport layer is usually 1 nm to 1000 nm.

[0045] The photoelectric conversion layer contains a perovskite compound, preferably contains a perovskite compound as a main component, and more preferably consists of a perovskite compound. The content of the perovskite compound in the photoelectric conversion layer is usually 60% by weight or more, preferably 80% by weight or more, more preferably 90% by weight or more, particularly preferably 95% by weight or more, and most preferably 100% by weight. The perovskite compound is as described above in the production method of the present invention. The solar cell of the present invention has excellent power generation efficiency due to the improved film quality of the photoelectric conversion layer. The thickness of the photoelectric conversion layer is usually 50 nm to 1000 nm, more preferably 200 nm to 600 nm.

[0046] In the solar cell of the present invention, the layers other than the photoelectric conversion layer can be formed by, for example, film formation using known methods.

[0047] The present invention also relates to an apparatus for manufacturing a perovskite solar cell. The manufacturing apparatus of the present invention may be an apparatus for carrying out the above-described method for manufacturing a perovskite solar cell of the present invention. FIG. 1 shows a schematic diagram of one embodiment of the manufacturing apparatus of the present invention. As shown in FIG. 1, the manufacturing apparatus 10 for a perovskite solar cell of the present invention includes a precursor solution application unit 1, a poor solvent application unit 2, and a control unit 3 that controls the precursor solution application unit 1 and the poor solvent application unit 2.

[0048] The precursor solution applying unit 1 applies a precursor solution of a perovskite compound in the form of droplets based on control by the control unit 3 (for example, a control signal supplied from the control unit 3). The precursor solution applying unit 1 includes, for example, a unit for storing the precursor solution, a unit for discharging the precursor solution, and a unit for receiving the control signal supplied from the control unit 3.

[0049] The poor solvent applying unit 2 applies the poor solvent as droplets based on the control by the control unit 3 (for example, a control signal supplied from the control unit 3). The poor solvent applying unit 2 includes, for example, a storage unit for the poor solvent, a discharge unit for the poor solvent, and a receiver for the control signal supplied from the control unit 3.

[0050] The control unit 3 controls the precursor solution application unit 1 and the poor solvent application unit 2 so that the poor solvent is applied as droplets before the droplets of the precursor solution adhering to the application surface combine with other droplets of the precursor solution. For example, the control unit 3 supplies control signals to the precursor solution application unit 1 and the poor solvent application unit 2. In one embodiment, the control unit 3 is a control computer.

[0051] The manufacturing apparatus 10 of the present invention is preferably used in the manufacturing method of the present invention in which a precursor solution and a poor solvent are applied by an inkjet method or a spray method, and more preferably in the manufacturing method of the present invention in which a precursor solution and a poor solvent are applied by an inkjet method. When the manufacturing apparatus 10 of the present invention is used in the manufacturing method of the present invention in which a precursor solution and a poor solvent are applied by an inkjet method, the manufacturing apparatus 10 of the present invention may be composed of an inkjet head equipped with a precursor solution application unit 1 and a poor solvent application unit 2, and a control unit 3 (e.g., a control computer) that controls these. In this embodiment, application of the precursor solution and the poor solvent by the inkjet method may be performed by fixing the application surface and moving the inkjet head, or by fixing the inkjet head and moving the application surface. [Example]

[0052] The present invention will be described in more detail below using examples, although the technical scope of the present invention is not limited to these examples.

[0053] Example 1 A glass plate coated with an indium tin oxide (ITO) film was used as the substrate. A solution containing the ternary system CsFAMAPbI3 together with 1-hexyl-3-methylimidazolium chloride (HMImCl) in a solvent consisting of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and γ-butyrolactone (GBL) (volume ratio: DMF:DMSO:GBL = 28:26:46) was prepared and used as the precursor solution. Tetralin was used as the antisolvent.

[0054] An industrial inkjet head (MH5420 manufactured by Ricoh Co., Ltd.) was filled with the precursor solution and the poor solvent. The precursor solution and the poor solvent were simultaneously applied onto the ITO film on the substrate by inkjet printing to obtain a wet film. The application conditions for the precursor solution and the poor solvent were as follows: inkjet head temperature: 54°C, frequency: 5 kHz, X pitch: 300, Y pitch: 600, drop number: 1, scan number: 1, and substrate temperature: room temperature (approximately 25°C). In Example 1, the poor solvent was applied as droplets before the droplets of the precursor solution combined with other droplets of the precursor solution, and the poor solvent combined with the droplets of the precursor solution.

[0055] Comparative Example 1 The precursor solution was applied onto the ITO film on the substrate by inkjet printing, and after the droplets of the precursor solution combined and spread to form a film (approximately 10 seconds later), the poor solvent was applied (sequentially) by inkjet printing to obtain a wet film. The application conditions for the precursor solution and the poor solvent were the same as in Example 1.

[0056] The wet films obtained in Example 1 (simultaneous application) and Comparative Example 1 (sequential application) were observed using an optical microscope. FIG. 2 shows a photograph of the appearance of the wet film of Example 1. FIG. 3 shows a photograph of the appearance of the wet film of Comparative Example 1. As shown in FIG. 2, when the precursor solution and poor solvent were applied simultaneously, the droplets of the precursor solution and poor solvent were thoroughly mixed, and the precursor solution was uniformly dispersed. On the other hand, as shown in FIG. 3, when the precursor solution and poor solvent were applied sequentially, the spread precursor solution and the poor solvent were completely separated.

[0057] When the wet film obtained in Example 1 was heated at 100°C, a film containing a perovskite compound was formed. Measurements such as transmission absorption spectroscopy and X-ray diffraction (XRD) confirmed that the formed film contained a perovskite compound. In Comparative Example 1, the precursor solution and the poor solvent were completely separated from each other in the obtained wet film, and film formation was not possible.

[0058] Example 2 The precursor solution and the poor solvent were simultaneously applied to the ITO film on the substrate by inkjet printing in the same manner as in Example 1, except that the poor solvent was changed from tetralin to 2-propanol, the inkjet head temperature was changed to 40°C, and the substrate temperature was changed to 60°C. A wet film was obtained by simultaneously applying the precursor solution and the poor solvent to the ITO film on the substrate by inkjet printing in the same manner as in Example 1. Figure 4 shows a photograph of the appearance of the wet film of Example 2. A line is drawn around the outer edge of the substrate in Figure 4. As shown in Figure 4, it was confirmed that by changing the poor solvent from tetralin to 2-propanol and adjusting the application conditions, the precursor solution was applied more uniformly in the wet film. In the wet film of Example 2, the precursor solution was applied as uniformly as when only the precursor solution was applied to the substrate. [Explanation of symbols]

[0059] 10: Perovskite solar cell manufacturing apparatus, 1: Precursor solution application section, 2: Poor solvent application section, 3: Control section

Claims

1. applying a precursor solution of a perovskite compound as droplets; a step of applying a poor solvent as droplets until the droplets of the precursor solution attached to the coating surface are combined with other droplets of the precursor solution; A method for producing a perovskite solar cell, comprising:

2. The method for producing a perovskite solar cell according to claim 1 , wherein the precursor solution and the poor solvent are applied by an inkjet method or a spray method.

3. 3. The method for producing a perovskite solar cell according to claim 1, wherein the poor solvent is at least one solvent selected from solvents having a relative dielectric constant of 20 or less and a boiling point of 100°C or more.

4. 3. The method for producing a perovskite solar cell according to claim 1, wherein the temperature of the precursor solution is 40°C or higher, and the temperature of the coating surface is 60°C or higher.

5. a precursor solution application unit that applies a precursor solution of a perovskite compound in the form of droplets; a poor solvent application unit that applies a poor solvent in the form of droplets; a control unit that controls the precursor solution application unit and the poor solvent application unit so that the poor solvent is applied as droplets before the droplets of the precursor solution attached to the application surface are combined with other droplets of the precursor solution; A manufacturing apparatus for a perovskite solar cell, comprising:

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