Perovskite precursor solution, perovskite thin film, preparation method of perovskite thin film, perovskite cell and photovoltaic module

Abstract

The invention relates to a perovskite precursor solution, a perovskite thin film, a preparation method of the perovskite thin film, a perovskite cell and a photovoltaic module. The perovskite precursor solution comprises a perovskite precursor component, a first solvent, a second solvent and a third solvent, the first solvent comprises diethoxymethane, the second solvent comprises at least one of an ester solvent, an amide solvent, a mercaptoalcohol solvent and a nitrile solvent, and the third solvent comprises at least one of a sulfoxide solvent and a ketone solvent. On the basis of a second solvent and a third solvent, low-polarity diethoxymethane is further matched, so that the dispersity of a perovskite precursor component in a perovskite precursor solution is effectively improved, the growth of perovskite crystals under a low-temperature condition is promoted, the perovskite precursor component can form a relatively good crystal structure after being annealed at a relatively low temperature, and the performance of the perovskite is improved. And the uniformity and the stability of the perovskite thin film can be effectively improved, so that the photoelectric conversion efficiency of the device is effectively improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a perovskite precursor solution, a perovskite film and a preparation method thereof, a perovskite cell and a photovoltaic module. Background Art

[0002] Perovskite Solar Cells (PSCs) have been rapidly developed in the field of solar technology since 2012 and have shown great application potential. Due to their unique optoelectronic properties, high photoelectric conversion efficiency and low material cost, PSCs have gradually become a powerful alternative to silicon-based solar cells in the photovoltaic field. The perovskite film layer in perovskite solar cells is usually prepared by a solution method. After the perovskite precursor solution is made into a wet film, the wet film needs to be annealed. However, traditional perovskite precursor solutions usually require an annealing temperature of more than 150°C. This high-temperature process limits the application of temperature-sensitive materials such as plastic flexible substrates, and also increases energy consumption and production costs in the manufacturing process.

[0003] Therefore, it is necessary to improve the traditional technology. Summary of the invention

[0004] Based on this, the present application provides a perovskite precursor solution, a perovskite film and a preparation method thereof, a perovskite cell and a photovoltaic module that can be annealed at a relatively low temperature and have a relatively high photoelectric conversion efficiency.

[0005] The technical solution of this application to solve the above technical problems is as follows.

[0006] On the one hand, the present application provides a perovskite precursor solution, including a perovskite precursor component, a first solvent, a second solvent and a third solvent, wherein the first solvent includes diethoxymethane, the second solvent includes at least one of an ester solvent, an amide solvent, a mercapto alcohol solvent and a nitrile solvent, and the third solvent includes at least one of a sulfoxide solvent and a ketone solvent.

[0007] In some embodiments, in the perovskite precursor solution, the volume ratio of the first solvent, the second solvent and the third solvent is 0.5~5:1:0.05~2.5.

[0008] In some embodiments, in the perovskite precursor solution, the volume ratio of the first solvent to the second solvent is 1-5:1.

[0009] In some of the embodiments, in the perovskite precursor solution, the volume ratio of the third solvent to the first solvent is 0.1-0.5:1.

[0010] In some embodiments, in the perovskite precursor solution, the ester solvent includes a lactone solvent having 3 to 8 carbon atoms; optionally, the ester solvent includes γ-butyrolactone; and / or,

[0011] The amide solvent includes at least one of N,N-dimethylformamide, N-methylformamide and N,N-dimethylacetamide; and / or,

[0012] The mercapto alcohol solvent includes 2-mercaptoethanol; and / or,

[0013] The nitrile solvent includes acetonitrile.

[0014] In some embodiments, in the perovskite precursor solution, the sulfoxide solvent includes at least one of dimethyl sulfoxide, methyl phenyl sulfoxide and tetramethylene sulfoxide; and / or,

[0015] The ketone solvent includes at least one of N-methylpyrrolidone and 1,3-dimethyl-2-imidazolidinone.

[0016] In some of the embodiments, in the perovskite precursor solution, the perovskite precursor components include a monovalent cationic compound and a divalent cationic compound; optionally, the monovalent cationic compound includes at least one of a monovalent organic cationic compound and a monovalent alkali metal compound; and / or,

[0017] The divalent cation in the divalent cation compound includes Pb 2+ Sn 2+ , Cu 2+ and Ge 2+ At least one of; and / or,

[0018] The anions in the divalent cationic compound include F - , Cl - Br, I - 、BF4 - PF6 - and SCN - At least one of .

[0019] In some embodiments, in the perovskite precursor solution, the monovalent organic cation in the monovalent organic cation compound includes at least one of an organic amine ion and an organic amidine ion; optionally, the organic amine ion includes CH3NH3 + and CH3(CH2) n NH3 + At least one of the organic amidine ions comprises HC(NH2)2 + 、C2H7N2 + and C6H5(CH2) nNH3 + At least one of, wherein n is an integer from 1 to 3; and / or,

[0020] The alkali metal ions in the monovalent alkali metal compound include Li + 、Na + , K + , Rb + and Cs + At least one of; and / or,

[0021] The anion in the monovalent organic cationic compound and the anion in the monovalent alkali metal compound each independently include F - , Cl - Br, I - 、BF4 - PF6 - and SCN - At least one of .

[0022] In some embodiments, in the perovskite precursor solution, the monovalent cationic compound includes at least one of formamidine iodide, formamidine bromide, formamidine chloride, methylammonium bromide, methylammonium chloride and cesium iodide; and / or,

[0023] The divalent cation compound includes at least one of lead iodide, tin iodide, lead bromide and tin bromide.

[0024] In some of the embodiments, in the perovskite precursor solution, the concentration of the perovskite precursor component in the perovskite precursor solution is 0.3 mmol / mL~3 mmol / mL.

[0025] On the one hand, the present application provides a method for preparing a perovskite precursor solution, comprising the following steps:

[0026] The perovskite precursor component, the first solvent, the second solvent and the third solvent are mixed to prepare a perovskite precursor solution; the first solvent includes diethoxymethane, the second solvent includes at least one of an ester solvent, an amide solvent, a mercapto alcohol solvent and a nitrile solvent, and the third solvent includes at least one of a sulfoxide solvent and a ketone solvent.

[0027] On one hand, the present application provides a perovskite film, which is prepared using the above-mentioned perovskite precursor solution or the perovskite precursor solution prepared by the above-mentioned preparation method.

[0028] On the one hand, the present application provides a method for preparing a perovskite film, comprising the following steps:

[0029] The perovskite precursor solution or the perovskite precursor solution prepared by the preparation method is made into a wet film;

[0030] The wet film is annealed to obtain the perovskite film.

[0031] In some of the embodiments, in the method for preparing the perovskite film, the temperature of the annealing treatment is 80° C. to 100° C.

[0032] On one hand, the present application provides a perovskite battery, comprising a first electrode, the above-mentioned perovskite film or the perovskite film prepared by the above-mentioned preparation method, and a second electrode which are stacked in sequence.

[0033] On the one hand, the present application provides a photovoltaic module, including the above-mentioned perovskite cell.

[0034] Compared with the prior art, the perovskite precursor solution of the present application has the following beneficial effects:

[0035] The perovskite precursor solution of the present application comprises a perovskite precursor component, a first solvent, a second solvent and a third solvent, wherein the first solvent comprises diethoxymethane, the second solvent comprises at least one of an ester solvent, an amide solvent, a mercapto alcohol solvent and a nitrile solvent, and the third solvent comprises at least one of a sulfoxide solvent and a ketone solvent; low-polarity diethoxymethane is further added to the second solvent and the third solvent to effectively improve the dispersibility of the perovskite precursor component in the perovskite precursor solution, promote the growth of perovskite crystals under low temperature conditions, enable the perovskite precursor component to be annealed at a relatively low temperature to form a better crystalline structure, and can effectively reduce the grain boundary defects in the perovskite film formed by the perovskite precursor solution, effectively improve the uniformity and stability of the perovskite film, thereby effectively improving the photoelectric conversion efficiency of the device.

[0036] The perovskite precursor solution of the present application requires a lower annealing temperature and can be applied to flexible substrates, providing new possibilities for the development of flexible solar cells; at the same time, it can reduce energy consumption, thereby reducing production costs. DETAILED DESCRIPTION

[0037] The present application will be further described in detail below in conjunction with the embodiments and examples. It should be understood that these embodiments and examples are only used to illustrate the present application and are not used to limit the scope of the present application. The purpose of providing these embodiments and examples is to make the understanding of the disclosure of the present application more thorough and comprehensive. It should also be understood that the present application can be implemented in many different forms, and is not limited to the embodiments and examples described herein. Those skilled in the art can make various changes or modifications without violating the connotation of the present application, and the equivalent form obtained also falls within the protection scope of the present application. For example, the features described or described as part of an embodiment can be combined in another embodiment in a suitable manner to produce a new embodiment. In addition, in the description below, a large number of specific details are given in order to provide a more comprehensive understanding of the present application, and it should be understood that the present application can be implemented without one or more of these details.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing implementation modes and embodiments and are not intended to limit this application.

[0039] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0040] In the present application, "plurality", "multiple", "multiple times", etc., unless otherwise specified, refer to a quantity greater than 2 or equal to 2. For example, "one or more" means one or greater than or equal to two.

[0041] As used herein, "combination thereof", "any combination thereof", "any combination thereof" etc. include all suitable combinations of any two or more of the listed items.

[0042] Herein, the “suitable” mentioned in “suitable combination”, “suitable method”, “any suitable method”, etc., shall be based on the ability to implement the technical solution of this application, solve the technical problems of this application, and achieve the expected technical effects of this application.

[0043] Herein, "preferred", "better", "more preferred", and "suitable" are only used to describe implementation methods or examples with better effects, and it should be understood that they do not constitute a limitation on the scope of protection of this application. If multiple "preferred" items appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "preferred" item is independent.

[0044] In the present application, "further", "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of the present application.

[0045] In this application, "optionally", "optional", and "optional" mean optional or dispensable, that is, any one of the two parallel schemes of "yes" or "no". If multiple "options" appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "optional" is independent.

[0046] In the present application, the terms "first", "second", "third", "fourth", etc. in "the first aspect", "the second aspect", "the third aspect", "the fourth aspect", etc. are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first", "second", "third", "fourth", etc. only serve the purpose of non-exhaustive enumeration and description, and it should be understood that they do not constitute a closed limitation on quantity.

[0047] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0048] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum value and the maximum value) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to the integers in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical range disclosed herein should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows broadly including numerical interval types such as percentage intervals, ratio intervals, and ratio intervals.

[0049] The temperature parameters in this application, unless otherwise specified, are allowed to be either constant temperature treatment or to vary within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are allowed.

[0050] In this application, the term "room temperature" or "normal temperature" generally refers to 4°C to 35°C, for example, 20°C ± 5°C. In some embodiments of this application, "room temperature" or "normal temperature" refers to 10°C to 30°C. In some embodiments of this application, "room temperature" or "normal temperature" refers to 20°C to 30°C.

[0051] In this application, when referring to the unit of a data range, if there is a unit only after the right endpoint, it means that the units of the left and right endpoints are the same. For example, 3~5 h means that the units of the left endpoint "3" and the right endpoint "5" are both h (hours).

[0052] All documents mentioned in this application are cited as references in this application, just as each document is cited as reference separately. Unless they conflict with the invention purpose and / or technical solution of this application, the cited documents involved in this application are cited with all contents and all purposes. When the cited documents are involved in this application, the definitions of relevant technical features, terms, nouns, phrases, etc. in the cited documents are also cited. When the cited documents are involved in this application, the examples and preferred methods of the cited relevant technical features can also be incorporated into this application as references, but are limited to the implementation of this application. It should be understood that when the cited content conflicts with the description in this application, the present application shall prevail or be modified adaptively according to the description of this application.

[0053] The mass or weight of the relevant components mentioned in the specification of the embodiments of the present application may not only refer to the specific content of each component, but also indicate the proportional relationship of the mass or weight between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the specification of the embodiments of the present application, it is within the scope disclosed in the specification of the embodiments of the present application. Specifically, the mass or weight described in the specification of the embodiments of the present application may be units known in the chemical industry such as μg, mg, g, and kg.

[0054] Traditional perovskite precursor solutions usually use DMF and DMSO solvents, and their highly polar dissolution system leads to an increase in grain boundary defects in the film, affecting the stability of the device.

[0055] An embodiment of the present application provides a perovskite precursor solution, comprising a perovskite precursor component, a first solvent, a second solvent and a third solvent, wherein the first solvent comprises diethoxymethane, the second solvent comprises at least one of an ester solvent, an amide solvent, a mercapto alcohol solvent and a nitrile solvent, and the third solvent comprises at least one of a sulfoxide solvent and a ketone solvent.

[0056] The perovskite precursor solution of the present application is further combined with low-polarity diethoxymethane on the basis of the second solvent and the third solvent, which effectively improves the dispersibility of the perovskite precursor components in the perovskite precursor solution, promotes the growth of perovskite crystals under low temperature conditions, and allows the perovskite precursor components to be annealed at a relatively low temperature to form a better crystalline structure. It can also effectively reduce the grain boundary defects in the perovskite film formed by the perovskite precursor solution, effectively improve the uniformity and stability of the perovskite film, and thus effectively improve the photoelectric conversion efficiency of the device.

[0057] Among them, the use of a specific type of low-polarity solvent diethoxymethane in combination with the second solvent and the third solvent can reduce the solvent-solute interaction in the perovskite precursor solution, allowing the perovskite precursor components to interact or react more freely, reducing the solute concentration fluctuation when the solvent evaporates; and can promote (during the annealing process) the perovskite precursor components in the perovskite precursor solution to form an ordered lattice structure, reducing thermodynamic or kinetic energy barriers; at the same time, the combination of the three solvents makes the perovskite precursor solution have better fluidity, which helps to promote the diffusion of the perovskite precursor components on the surface or inside the film, thereby accelerating the crystallization process.

[0058] A specific type of low polarity solvent diethoxymethane cooperates with the second solvent and the third solvent to help complete the phase transformation and crystal growth at a lower temperature, thereby reducing the temperature required for annealing.

[0059] The perovskite precursor solution of the present application requires a relatively low annealing temperature and can be applied to flexible substrates that are relatively sensitive to temperature. It can achieve a good thin film forming effect on the flexible substrate, providing new possibilities for the development of flexible solar cells; at the same time, it can reduce energy consumption, thereby reducing production costs and improving environmental protection.

[0060] Among them, diethoxymethane, whose English name is Diethoxymethane, is abbreviated as DEM.

[0061] In some of the examples, in the perovskite precursor solution, the volume ratio of the first solvent, the second solvent, and the third solvent is 0.5~5:1:0.05~2.5.

[0062] It can be understood that in some of the examples, in the perovskite precursor solution, the volume ratio of the first solvent to the second solvent is 0.5~5:1.

[0063] It is understood that the volume ratio of the first solvent to the second solvent includes, but is not limited to, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, 2.5:1, 2.6:1, 2.7:1, 2.8:1. : 8:1, 2.9:1, 3:1, 3.1:1, 3.2:1, 3.3:1, 3.4:1, 3.5:1, 3.6:1, 3.7:1, 3.8:1, 3.9:1, 4:1, 4.1:1, 4.2:1, 4.3:1, 4.4:1, 4.5:1, 4.6:1, 4.7:1, 4.8:1, 4.9:1, 5:1; in some examples, the value can be within the range formed by any two of these point values ​​as end values, the same below.

[0064] In some of the examples, in the perovskite precursor solution, the volume ratio of the first solvent to the second solvent is 1 to 5:1.

[0065] Optionally, the volume ratio of the first solvent to the second solvent is 1-3:1.

[0066] Furthermore, the volume ratio of the first solvent to the second solvent is 1.5-2.5:1.

[0067] In some of the examples, in the perovskite precursor solution, the volume ratio of the third solvent to the first solvent is 0.1~0.5:1.

[0068] It can be understood that the volume ratio of the third solvent to the first solvent includes but is not limited to 0.1:1, 0.12:1, 0.15:1, 0.18:1, 0.2:1, 0.22:1, 0.25:1, 0.28:1, 0.3:1, 0.32:1, 0.33:1, 0.35:1, 0.38:1, 0.4:1, 0.42:1, 0.145:1, 0.48:1, and 0.5:1.

[0069] In some of the examples, in the perovskite precursor solution, the volume ratio of the third solvent to the first solvent is 0.1~0.4:1.

[0070] Optionally, the volume ratio of the third solvent to the first solvent is 0.25~0.4:1.

[0071] Furthermore, the volume ratio of the third solvent to the first solvent is 0.25~0.3:1.

[0072] By controlling the ratio between the solvents, the uniformity and stability of the perovskite film can be further improved, thereby effectively improving the photoelectric conversion efficiency and stability of the device.

[0073] In some of the examples, in the perovskite precursor solution, the ester solvent includes a lactone solvent having 3 to 8 carbon atoms.

[0074] It is understood that the lactone solvents having 3 to 8 carbon atoms include, but are not limited to, at least one of β-propiolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, enantholactone and octanolactone.

[0075] Optionally, the ester solvent includes gamma-butyrolactone (GBL).

[0076] In some of the examples, in the perovskite precursor solution, the amide solvent includes at least one of N,N-dimethylformamide (DMF), N-methylformamide (NMF) and N,N-dimethylacetamide (DMAC).

[0077] It is understood that the mercapto alcohol solvents include, but are not limited to, at least one of 2-mercaptoethanol, 3-mercaptopropanol, 4-mercaptobutanol, 6-mercaptohexanol and benzylmercaptoethanol.

[0078] In some of these examples, in the perovskite precursor solution, the mercaptoalcohol solvent includes 2-mercaptoethanol (2-Me).

[0079] It is understood that the nitrile solvent includes but is not limited to at least one of acetonitrile, propionitrile, butyronitrile, valeronitrile, adiponitrile and benzonitrile.

[0080] In some of these examples, the nitrile solvent in the perovskite precursor solution includes acetonitrile (ACN).

[0081] In some of the examples, in the perovskite precursor solution, the sulfoxide solvent includes at least one of dimethyl sulfoxide (DMSO), methyl phenyl sulfoxide (MPSO) and tetramethylene sulfoxide (TMSO).

[0082] In some of the examples, in the perovskite precursor solution, the ketone solvent includes at least one of N-methylpyrrolidone (NMP) and 1,3-dimethyl-2-imidazolidinone (DMI).

[0083] In some of these examples, in the perovskite precursor solution, the perovskite precursor components include a monovalent cationic compound and a divalent cationic compound.

[0084] In some of these examples, in the perovskite precursor component of the perovskite precursor solution, the monovalent cationic compound includes at least one of a monovalent organic cationic compound and a monovalent alkali metal compound.

[0085] Optionally, the monovalent organic cation in the monovalent organic cationic compound includes at least one of an organic amine ion and an organic amidine ion.

[0086] Further, the organic amine ion includes CH3NH3 + (MA + ) and CH3(CH2) n NH3 + At least one of; further, the organic amidine ion includes HC (NH2) 2 + (FA + )、C2H7N2 + and C6H5(CH2) n NH3 + At least one of; wherein n is an integer from 1 to 3.

[0087] It is understandable that CH3(CH2) n NH3 +Including CH3CH2NH3 + 、CH3(CH2)2NH3 + 、CH3(CH2)3NH3 + ,C6H5(CH2) n NH3 + Including C6H5CH2NH3 + 、C6H5(CH2)2NH3 + 、C6H5(CH2)3NH3 + .

[0088] Optionally, the alkali metal ion in the monovalent alkali metal compound includes Li + 、Na + , K + , Rb + and Cs + At least one of .

[0089] Optionally, the anion in the monovalent organic cationic compound and the anion in the monovalent alkali metal compound each independently include F - , Cl - Br, I - 、BF4 - PF6 - and SCN - At least one of .

[0090] In some of the examples, in the perovskite precursor component of the perovskite precursor solution, the monovalent cationic compound includes at least one of formamidine iodide (FAI), formamidine bromide (FABr), formamidine chloride (FACl), methylamine iodide (MAI), methylamine bromide (MABr), methylamine chloride (MACl) and cesium iodide (CsI).

[0091] In some of these examples, the divalent cations in the divalent cation compound in the perovskite precursor component of the perovskite precursor solution include Pb 2+ Sn 2+ , Cu 2+ and Ge 2+ At least one of .

[0092] In some of these examples, the anions in the divalent cationic compound in the perovskite precursor component of the perovskite precursor solution include F - , Cl - Br, I - 、BF4 - PF6 - and SCN - At least one of .

[0093] In some of these examples, in the perovskite precursor component of the perovskite precursor solution, the divalent cation compound includes at least one of lead iodide (PbI2), tin iodide, lead bromide, and tin bromide.

[0094] In some of these examples, in the perovskite precursor solution, the concentration of the perovskite precursor component in the perovskite precursor solution is 0.3 mmol / mL~3 mmol / mL.

[0095] It can be understood that the perovskite precursor component includes a monovalent cationic compound and a divalent cationic compound, and the concentration of the perovskite precursor component in the perovskite precursor solution is 0.3 mmol / mL~3 mmol / mL, which means that the concentrations of the monovalent cationic compound and the divalent cationic compound are independently 0.3 mmol / mL~3 mmol / mL; further, the concentration of the perovskite precursor component in the perovskite precursor solution includes but is not limited to 0.3 mmol / mL, 0.4 mmol / mL, 0.5 mmol / mL, 0.6 mmol / mL, 0.7 mmol / mL, 0.8 mmol / mL, 0.9 mmol / mL, 1 mmol / mL, 1.1 mmol / mL, 1.2 mmol / mL, 1.3 mmol / mL, 1.4 mmol / mL, 1.5 mmol / mL, 1.6 mmol / mL, 1.7 mmol / mL, 1.8 mmol / mL, 1.9 mmol / mL, 2 mmol / mL, 2.1 mmol / mL, 2.2 mmol / mL, 2.3 mmol / mL, 2.4 mmol / mL, 2.5 mmol / mL, 2.6 mmol / mL, 2.7 mmol / mL, 2.8 mmol / mL, 2.9 mmol / mL, 3 mmol / mL.

[0096] In some of these examples, the perovskite precursor solution also includes a crystallization regulating component.

[0097] Optionally, in the crystallization regulating component, the cation includes Cs + 、HC(NH2)2 + 、CH3NH3 + , Rb + and Pb 2+ At least one of the anions includes F - , Cl - Br, I - 、BF4 - PF6 - and SCN - At least one of .

[0098] Further, the crystallization regulating component includes at least one of methylammonium chloride (MACl) and lead chloride (PbCl2).

[0099] Methylamine chloride has a certain regulatory effect on the perovskite structure and can optimize the lattice arrangement of the material. Lead chloride can increase the concentration of lead in the solution, thereby affecting the solubility and supersaturation of the precursor solution. An appropriate amount of lead chloride helps to control the concentration of lead ions and avoid excessive concentrations of lead ions leading to irregular crystallization or the formation of unstable perovskite structures. Among them, the presence of chloride ions helps to reduce the lattice defects of the perovskite film during crystal growth and improve the crystallinity and uniformity of the film.

[0100] It can be understood that the present application provides a perovskite precursor solution, and the prepared perovskite film includes an ABX3 type perovskite compound, such as FA 0.9 Cs 0.1 PbI3.

[0101] In some of these examples, the molar ratio of the crystallization-modulating component to ABX3 is 0.05-0.3:1.

[0102] Furthermore, the molar ratio of MACl to ABX3 is 0.1~0.2:1.

[0103] Furthermore, the molar ratio of PbCl2 to ABX3 is 0.05~0.1:1.

[0104] An embodiment of the present application provides a method for preparing a perovskite precursor solution, comprising the following steps:

[0105] The perovskite precursor component, the first solvent, the second solvent and the third solvent are mixed to prepare a perovskite precursor solution; the first solvent includes diethoxymethane, the second solvent includes at least one of an ester solvent, an amide solvent, a mercapto alcohol solvent and a nitrile solvent, and the third solvent includes at least one of a sulfoxide solvent and a ketone solvent.

[0106] It can be understood that the preparation method of the perovskite precursor solution provided in the present application can prepare the above-mentioned perovskite precursor solution, and the above-mentioned perovskite precursor solution can also be prepared by the preparation method of the perovskite precursor solution provided in the present application, and the characteristics between the two can be mutually applicable.

[0107] In some of the examples, the method for preparing the perovskite precursor solution further includes filtering the obtained mixed solution after mixing the perovskite precursor components, the first solvent, the second solvent and the third solvent.

[0108] The method for preparing a perovskite precursor solution provided in the present application can obtain a perovskite film with good uniformity and stability at a relatively low temperature using the prepared perovskite precursor solution.

[0109] One embodiment of the present application provides a perovskite film, which is prepared using the above-mentioned perovskite precursor solution or the perovskite precursor solution prepared by the above-mentioned preparation method.

[0110] The perovskite film provided in the present application has a high photoelectric conversion efficiency.

[0111] An embodiment of the present application provides a method for preparing a perovskite film, comprising the following steps:

[0112] The perovskite precursor solution or the perovskite precursor solution prepared by the preparation method is made into a wet film;

[0113] The wet film is annealed to obtain a perovskite film.

[0114] The method for preparing the perovskite film provided in the present application uses the above-mentioned perovskite precursor solution or the perovskite precursor solution prepared by the above-mentioned preparation method, which can be annealed at a lower temperature, and the prepared perovskite film has good uniformity and stability, thereby effectively improving the photoelectric conversion efficiency of the device.

[0115] In some of these examples, in the method for preparing the perovskite film, the temperature of the annealing treatment is 80°C~100°C.

[0116] It will be appreciated that the temperature of the annealing treatment includes but is not limited to 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C, and 100°C.

[0117] It can be understood that the present application does not limit the method of forming the wet film, including but not limited to at least one of slit coating, spin coating, spraying, blade coating, inkjet printing, screen printing, etc.

[0118] In some of the examples, in the method for preparing the perovskite thin film, the manner of forming the wet film includes a slit coating method.

[0119] Furthermore, the coating speed of the slit coating method is 5 mm / s to 20 mm / s.

[0120] One embodiment of the present application provides a perovskite cell, comprising a first electrode, the above-mentioned perovskite film or the perovskite film prepared by the above-mentioned preparation method, and a second electrode which are sequentially stacked.

[0121] The perovskite cell provided in the present application includes the above-mentioned perovskite film or the perovskite film prepared by the above-mentioned preparation method. The perovskite cell provided in the present application includes the above-mentioned perovskite film, and thus has at least the same advantages as the above-mentioned perovskite film, and has higher photoelectric conversion efficiency and stable performance.

[0122] In some of the examples, in the perovskite cell, the perovskite cell further includes a hole transport layer and an electron transport layer, one of the hole transport layer and the electron transport layer is disposed between the first electrode and the perovskite film, and the other of the hole transport layer and the electron transport layer is disposed between the perovskite film and the second electrode.

[0123] It can be understood that when the hole transport layer is disposed between the first electrode and the perovskite film, the electron transport layer is disposed between the perovskite film and the second electrode; when the electron transport layer is disposed between the first electrode and the perovskite film, the hole transport layer is disposed between the perovskite film and the second electrode. That is, in some examples, the perovskite cell includes a first electrode, a hole transport layer, a perovskite film, an electron transport layer, and a second electrode stacked in sequence; in other examples, the perovskite cell includes a first electrode, an electron transport layer, a perovskite film, a hole transport layer, and a second electrode stacked in sequence.

[0124] It can be understood that the hole transport layer and the electron transport layer can be independently one layer or two layers or more.

[0125] In some of the examples, in the perovskite cell, the electron transport layer includes but is not limited to at least one of C60, PCBM, TiO2 and SnO2.

[0126] In some of the examples, in the perovskite cell, the hole transport layer includes but is not limited to at least one of NiOx, poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid (PEDOT:PSS), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), (2-(9H-carbazol-9-yl)ethyl)phosphonic acid (2PACz), [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz), [4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl]phosphonic acid (MeO-4PACz), 2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenylamine)9,9′-spirobifluorene (Spiro-OMeTAD) and 3-hexylthiophene polymer (P3HT).

[0127] In some of the examples, in the perovskite cell, one of the first electrode and the second electrode is a transparent conductive electrode, and the other is one of a transparent conductive electrode and a metal electrode;

[0128] In some of the examples, in the perovskite cell, at least one of the first electrode and the second electrode is a transparent conductive electrode.

[0129] In some of the examples, in the perovskite cell, one of the first electrode and the second electrode is a transparent conductive electrode, and the other is one of a transparent conductive electrode and a metal electrode.

[0130] It can be understood that in the perovskite battery, the first electrode and the second electrode may be both transparent conductive electrodes; the first electrode may be a transparent conductive electrode and the second electrode may be a metal electrode; or the first electrode may be a metal electrode and the second electrode may be a transparent conductive electrode.

[0131] In some of these examples, in the perovskite cell, the metal electrode includes at least one of gold (Au), silver (Ag), and copper (Cu).

[0132] In some of these examples, in the perovskite cell, the transparent conductive electrode includes at least one of indium tin oxide (ITO), fluorine-doped indium tin oxide (FTO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), and aluminum-doped zinc oxide (AZO).

[0133] In some of the examples, in the perovskite cell, the thickness of the first electrode and the second electrode are independently 20 nm to 200 nm.

[0134] It can be understood that the thickness of the first electrode and the second electrode independently include but are not limited to 20 nm, 50 nm, 80 nm, 100 nm, 120 nm, 150 nm, 180 nm, and 200 nm.

[0135] An embodiment of the present application provides a method for preparing a perovskite battery, comprising the following steps:

[0136] The perovskite precursor solution or the perovskite precursor solution prepared by the preparation method is placed on the first electrode, and a perovskite film is formed on the first electrode after annealing;

[0137] A second electrode is formed on a surface of the perovskite film away from the first electrode.

[0138] It can be understood that the features of the above-mentioned method for preparing the perovskite film are applicable to the step of preparing the perovskite film in the method for preparing the perovskite battery provided in the present application.

[0139] In some of the examples, the method for preparing the perovskite battery further includes:

[0140] One of the hole transport layer and the electron transport layer is disposed between the first electrode and the perovskite film, and the other of the hole transport layer and the electron transport layer is disposed between the perovskite film and the second electrode.

[0141] It can be understood that the present application does not limit the formation method of the hole transport layer and the second electrode layer, and the commonly used formation methods in the art can be used, including but not limited to one of magnetron sputtering, spin coating, slit coating and evaporation.

[0142] In some of the examples, the method for preparing the perovskite cell further includes a step of pre-treating the transparent conductive electrode before forming a film layer on the surface of the transparent conductive electrode.

[0143] In some of these examples, the preprocessing steps include:

[0144] The transparent conductive electrode is cleaned, dried and surface treated in sequence.

[0145] It is understood that the cleaning agent used for cleaning includes but is not limited to at least one of water, acetone, isopropyl alcohol, ethanol and glass cleaning agent.

[0146] It can be understood that the preparation method of the perovskite battery provided in the present application can produce the above-mentioned perovskite battery, and the above-mentioned perovskite battery can also be produced by the preparation method of the perovskite battery provided in the present application.

[0147] One embodiment of the present application provides a photovoltaic module, including the above-mentioned perovskite cell or the perovskite cell prepared by the above-mentioned preparation method.

[0148] It can be understood that photovoltaic modules can be used in photovoltaic power stations, such as ground power stations, rooftop power stations, water power stations, etc., and can also be used in equipment or devices that use solar energy to generate electricity, such as user solar power supplies, solar street lights, solar cars, solar buildings, etc. It can also be understood that the application scenarios of photovoltaic systems include but are not limited to this, that is, photovoltaic systems can be used in all fields that require solar energy to generate electricity. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a junction box and an inverter. The photovoltaic array can be an array combination of multiple photovoltaic modules. For example, multiple photovoltaic modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the junction box. The junction box can converge the current generated by the photovoltaic array. The converged current flows through the inverter and is converted into the alternating current required by the mains power grid, and then connected to the mains network to achieve solar power supply.

[0149] The photovoltaic module provided in the present application can be used in, but is not limited to, electrical devices such as vehicles, ships or aircraft.

[0150] The embodiments of the present application provide an electric device, which may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0151] The present application is further described in detail below in conjunction with specific implementation methods, but the implementation methods of the present application are not limited thereto.

[0152] Example 1

[0153] (1) The FTO conductive glass substrate is laser scribed by P1, cleaned and dried with nitrogen;

[0154] (2) sputtering a NiOx layer on the FTO conductive substrate treated in step (1) by PVD;

[0155] (3) Dissolve MeO-4PACz in ethanol at a concentration of 0.5 mg / mL to form a SAM solution, apply the SAM solution to the surface of the NiOx layer prepared in step (2) away from the conductive substrate by a slit coating method, and move the solution to a nitrogen oven for annealing at 100°C for 10 min to prepare a SAM layer;

[0156] (4) Mix FAI, PbI2, and CsI powders according to Cs 0.1 FA 0.9 PbI3 molar ratio, then add MACl and PbCl2, MACl and Cs 0.1 FA 0.9 The molar ratio of PbI3 is 0.1:1, PbCl2 and Cs 0.1 FA 0.9 The molar ratio of PbI3 was 0.05:1, and a mixed solvent was added to dissolve to obtain a Cs 0.1 FA 0.9 PbI3 perovskite precursor solution; wherein the mixed solvent comprises a first solvent (DEM), a second solvent (DMF) and a third solvent (NMP) in a volume ratio of 2:1:0.5; the perovskite precursor solution is placed on the surface of the SAM layer prepared in step (3) away from the NiOx layer by a slit coating method, and then moved to a nitrogen oven for annealing at 85°C for 30 min to prepare a perovskite light absorbing layer;

[0157] (5) On the surface of the perovskite light absorbing layer prepared in step (4) away from the SAM layer, 30 nm thick C60, 20 nm thick SnO2 and 120 nm thick Cu are sequentially deposited by vacuum evaporation to prepare a perovskite solar cell module.

[0158] Examples 2 to 7 are basically the same as Example 1, except that the types of the first solvent, the second solvent and the third solvent in step (4) and the ratios therebetween are partially different, as shown in Table 1 for details.

[0159] Comparative Example 1

[0160] The method is basically the same as Example 1, except that in step (4), DEM is not added, and the mixed solvent is DMF and NMP in a volume ratio of 6:1; and the mixture is moved to a nitrogen oven and annealed at 130° C. for 30 min.

[0161] Comparative Example 2

[0162] The method is basically the same as Example 1, except that, in Comparative Example 2, the first solvent (DEM) in step (4) of Example 1 is replaced by an equal volume of TBA (tert-butyl alcohol).

[0163] Comparative Example 3

[0164] The method is basically the same as Example 1, except that, in Comparative Example 3, the first solvent (DEM) in step (4) of Example 1 is replaced by an equal volume of DMSO.

[0165] Comparative Example 4

[0166] The method is basically the same as Example 1, except that in Comparative Example 4, the second solvent (DMF) in step (4) of Example 1 is replaced by an equal volume of DMSO.

[0167] The types and ratios of solvents in the perovskite precursor solutions used in preparing the perovskite solar cell modules in various embodiments and comparative examples are shown in Table 1.

[0168] Table 1

[0169]

[0170] The "volume ratio" in Table 1 refers to the volume ratio among the first solvent, the second solvent and the third solvent.

[0171] The perovskite solar cell modules prepared in each embodiment and comparative example were subjected to performance tests of open circuit voltage, short circuit current density, fill factor and energy conversion efficiency. The IV curve was used for testing. The test conditions were: AM 1.5G standard solar spectrum, irradiance of 1000W / m 2 .

[0172] The experimental test results are detailed in Table 2. PCE represents the photoelectric conversion efficiency, in %, Voc represents the open circuit voltage, in V, and Jsc represents the short circuit current density, in mA / cm 2, FF stands for fill factor, the unit is %.

[0173] Table 2

[0174]

[0175] As shown in Table 2, compared with the perovskite solar cell modules prepared by the traditional solvent system in Comparative Examples 1 to 4, the performance of the perovskite solar cell modules prepared by the mixed co-solvent system formed by DEM and other solvents in Examples 1 to 7 is comprehensively improved. Thanks to the low polarity and high volatility of DEM, the dispersibility of the components in the precursor solution can be effectively improved, and the growth of perovskite crystals can be promoted under low temperature conditions, and the grain boundary defects can be reduced, so that the open circuit voltage of the module is greatly improved. Compared with the perovskite battery prepared by the traditional high temperature process, the perovskite light absorption layer prepared in the embodiment adopts a low temperature process of 85°C, which is more suitable for the production of large-area perovskite photovoltaic modules and has higher adaptability to flexible substrates, which is conducive to the industrial development of perovskite solar cells.

[0176] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0177] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solution of the present application in detail, but it cannot be understood as limiting the scope of protection of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of this application shall be based on the content of the attached claims, and the description can be used to interpret the content of the claims.

Claims

1. A perovskite precursor solution, characterized in that: The invention comprises a perovskite precursor component, a first solvent, a second solvent and a third solvent, wherein the first solvent comprises diethoxymethane, the second solvent comprises at least one of an ester solvent, an amide solvent, a mercapto alcohol solvent and a nitrile solvent, and the third solvent comprises at least one of a sulfoxide solvent and a ketone solvent.

2. The perovskite precursor solution according to claim 1, characterized in that The volume ratio of the first solvent, the second solvent and the third solvent is 0.5-5:1:0.05-2.

5.

3. The perovskite precursor solution according to claim 2, characterized in that The volume ratio of the first solvent to the second solvent is 1-5:1; and / or, The volume ratio of the third solvent to the first solvent is 0.1-0.5:

1.

4. The perovskite precursor solution according to any one of claims 1 to 3, characterized in that The ester solvent includes a lactone solvent having 3 to 8 carbon atoms; optionally, the ester solvent includes γ-butyrolactone; and / or, The amide solvent includes at least one of N,N-dimethylformamide, N-methylformamide and N,N-dimethylacetamide; and / or, The mercapto alcohol solvent includes 2-mercaptoethanol; and / or, The nitrile solvent includes acetonitrile; and / or, The sulfoxide solvent includes at least one of dimethyl sulfoxide, methyl phenyl sulfoxide and tetramethylene sulfoxide; and / or, The ketone solvent includes at least one of N-methylpyrrolidone and 1,3-dimethyl-2-imidazolidinone.

5. The perovskite precursor solution according to any one of claims 1 to 3, characterized in that: The perovskite precursor component comprises a monovalent cationic compound and a divalent cationic compound; optionally, the monovalent cationic compound comprises at least one of a monovalent organic cationic compound and a monovalent alkali metal compound; and / or, The divalent cation in the divalent cation compound includes Pb 2+ Sn 2+ , Cu 2+ and Ge 2+ At least one of; and / or, The anions in the divalent cationic compound include F - , Cl - Br, I - 、BF4 - PF6 - and SCN - At least one of .

6. The perovskite precursor solution according to claim 5, characterized in that The monovalent organic cation in the monovalent organic cationic compound includes at least one of an organic amine ion and an organic amidine ion; optionally, the organic amine ion includes CH3NH3 + and CH3(CH2) n NH3 + At least one of the organic amidine ions comprises HC(NH2)2 + 、C2H7N2 + and C6H5(CH2) n NH3 + At least one of, wherein n is an integer from 1 to 3; and / or, The alkali metal ions in the monovalent alkali metal compound include Li + 、Na + , K + , Rb + and Cs + At least one of; and / or, The anion in the monovalent organic cationic compound and the anion in the monovalent alkali metal compound each independently include F - , Cl - Br, I - 、BF4 - PF6 - and SCN - At least one of .

7. The perovskite precursor solution according to claim 5, characterized in that The monovalent cationic compound comprises at least one of formamidine iodide, formamidine bromide, formamidine chloride, methylammonium bromide, methylammonium chloride and cesium iodide; and / or, The divalent cation compound includes at least one of lead iodide, tin iodide, lead bromide and tin bromide.

8. The perovskite precursor solution according to any one of claims 1 to 3, 6 to 7, characterized in that: The concentration of the perovskite precursor component in the perovskite precursor solution is 0.3 mmol / mL to 3 mmol / mL.

9. A method for preparing a perovskite precursor solution, characterized in that: The following steps are involved: The perovskite precursor component, the first solvent, the second solvent and the third solvent are mixed to prepare a perovskite precursor solution; the first solvent includes diethoxymethane, the second solvent includes at least one of an ester solvent, an amide solvent, a mercapto alcohol solvent and a nitrile solvent, and the third solvent includes at least one of a sulfoxide solvent and a ketone solvent.

10. A perovskite film, characterized in that: It is prepared using the perovskite precursor solution according to any one of claims 1 to 8 or the perovskite precursor solution prepared by the preparation method according to claim 9.

11. A method for preparing a perovskite film, characterized in that: The following steps are involved: Forming a wet film from the perovskite precursor solution according to any one of claims 1 to 8 or the perovskite precursor solution prepared by the preparation method according to claim 9; The wet film is annealed to obtain the perovskite film.

12. The method for preparing a perovskite thin film according to claim 11, characterized in that: The annealing treatment is performed at a temperature of 80°C to 100°C.

13. A perovskite battery, characterized in that: It comprises a first electrode, a perovskite film as claimed in claim 11 or a perovskite film prepared by the preparation method as claimed in any one of claims 11 to 12, and a second electrode which are stacked in sequence.

14. A photovoltaic module, characterized in that: Comprising the perovskite cell as claimed in claim 13.

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