Perovskite precursor solution, perovskite solar cell and manufacturing method thereof, and power consumption device

Abstract

This application relates to a perovskite precursor solution, a perovskite solar cell and its manufacturing method, and a power consumption device. The perovskite precursor solution has a composition including a perovskite precursor material and a solvent, the solvent including a first solvent and a second solvent. The perovskite precursor solution is advantageous for realizing the production of high-quality perovskite films in combination with an air knife process.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application references Chinese patent application No. 2023100785167, filed on January 18, 2023, entitled "Perovskite precursor solution, perovskite solar cell and manufacturing method thereof, and power consumption device," the entire contents of which are incorporated herein by reference. [Technical Field]

[0002] The present application relates to the technical field of solar cells, and in particular to perovskite precursor solutions, perovskite solar cells and their manufacturing methods, and power consumption devices. [Background technology]

[0003] Perovskite solar cells are solar cells that use perovskite-type organometal halide semiconductors as light-absorbing materials. They belong to the third generation of solar cells and are also called new concept solar cells. Here, the perovskite film is the main functional layer of perovskite solar cells.

[0004] The production of perovskite films generally requires three steps: wet film coating, solvent quenching, and annealing. In device manufacturing, a wet film is generally coated using spin coating, a poor solvent is added dropwise to perform solvent quenching, and then the perovskite film is formed by annealing under certain temperature and time conditions to crystallize it. However, many perovskite films produced using this method have problems with the quality of the film layer (density, flatness, and uniformity). Summary of the Invention

[0005] The present application provides a perovskite precursor solution, a perovskite solar cell and its manufacturing method, and a power consumption device, in which the perovskite film layer in the perovskite solar cell is uniform and of high quality.

[0006] A first aspect of the present application provides a perovskite solar cell, the cell comprising a transparent electrode, a first functional layer, a perovskite film, a second functional layer, and a second electrode layer, which are stacked together, and wherein the size distribution of perovskite crystal grains in the perovskite film is ≧1.2 μm.

[0007] The size distribution of the perovskite crystal grains in the perovskite film of the perovskite solar cell according to the present invention is ≧1.2 μm, which is difficult to achieve using conventional processes, and the flatness of the perovskite film is significantly improved, further effectively improving the cell efficiency.

[0008] In one embodiment thereof, the size distribution of the perovskite crystal grains in the perovskite film is ≧2 μm, and further, the size distribution of the perovskite crystal grains in the perovskite film is 2 μm to 3 μm.

[0009] A second aspect of the present application provides a perovskite precursor solution, the composition of which comprises a perovskite precursor material and a solvent, the solvent comprising a first solvent and a second solvent; (1) The boiling point of the first solvent is lower than the boiling point of the second solvent, and optionally, the absolute value of the difference between the boiling points of the first solvent and the second solvent is ≧30, and further optionally, the absolute value of the difference between the boiling points of the first solvent and the second solvent is 50 to 150; (2) The saturated vapor pressure of the first solvent is greater than the saturated vapor pressure of the second solvent, and optionally the saturated vapor pressure of the first solvent is 8 times or more the saturated vapor pressure of the second solvent, and more optionally the saturated vapor pressure of the first solvent is 10 to 300 times the saturated vapor pressure of the second solvent.

[0010] The present application employs and blends two solvents with different boiling points and / or different saturated vapor pressures to adjust the process window and further adapt it to the air knife process, thereby enabling the production of high-quality perovskite films.

[0011] In one embodiment thereof, the first solvent is (1) The boiling point is 70°C to 160°C, and optionally, the boiling point is 75°C to 155°C; (2) The saturated vapor pressure is greater than 2 mm Hg at 20°C, and optionally, the saturated vapor pressure is 2.5 mm Hg to 200 mm Hg at 20°C.

[0012] In one embodiment thereof, the second solvent is (1) The boiling point is 130°C to 220°C, and optionally, the boiling point is 150°C to 210°C; (2) The saturated vapor pressure is 3 mm Hg or less at 20°C, and optionally, the saturated vapor pressure is 0.2 mm Hg to 3 mm Hg at 20°C.

[0013] In one embodiment thereof, the volume ratio of the first solvent to the second solvent is Y, and 20≧Y≧1.

[0014] In one embodiment, the solid content of the perovskite precursor solution is 10% to 40%, and optionally the solid content of the perovskite precursor solution is 10% to 25%.

[0015] In one embodiment thereof, the first solvent comprises one or more of acetonitrile, dioxane, ethylene glycol monomethyl ether, and N,N-dimethylformamide.

[0016] In one embodiment thereof, the second solvent includes one or more of N,N-dimethylformamide, N,N-diethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, and γ-butyrolactone.

[0017] In one embodiment thereof, the perovskite precursor material has a general structural formula of ABX3 or A2CDX6, where A is a monovalent cation, B is a divalent metal cation, C and D are monovalent and trivalent metal cations, respectively, and X is a monovalent anion; Optionally, A comprises one or more of Cs+, K+, Rb+, monovalent amine-based cations, and monovalent amidine-based cations; Optionally, B comprises one or more of Pb2+, Sn2+, Fe2+, Mn2+, Ni2+, Ge2+, Co2+ and Sb2+; optionally, C comprises one or more of Cs+, Ag+, K+, and Ru+; Optionally, D comprises one or more of Bi3+, Ni3+, Fe3+, and Cu3+; Optionally, X comprises one or more of I − , Br − and Cl − .

[0018] A third aspect of the present application provides a method for manufacturing a perovskite solar cell, the method comprising: Producing a first functional layer on the surface of the transparent electrode; producing a perovskite film on a surface of the first functional layer; fabricating a second functional layer on a surface of the perovskite film; and forming a second electrode layer on the surface of the second functional layer, producing a perovskite film on a surface of the first functional layer, applying a perovskite precursor solution on the surface of the first functional layer by slit coating and quenching a solvent in the perovskite precursor solution by an air knife process to form an intermediate film, wherein the perovskite precursor solution is the perovskite precursor solution according to the second aspect; and annealing the intermediate film to produce the perovskite film.

[0019] The above manufacturing method employs the above perovskite precursor solution and, in combination, employs an air knife process to quench the solvent in the perovskite precursor solution, and by controlling the solvent blending and the air knife process, can synergistically realize the production of high-quality perovskite films, and is more suitable for industrial production of large-area perovskite films.

[0020] In one embodiment, the volume ratio of the first solvent to the second solvent is Y, the slit coating and the air knife process are performed synchronously, and 20≧Y≧6, optionally 15≧Y≧6.

[0021] In one embodiment thereof, the method for producing the perovskite film comprises: (1) Along the coating direction of the slit coating, the air knife of the air knife process is located 5 cm to 30 cm behind the knife head of the slit coating, and optionally, the air knife of the air knife process is located 10 cm to 20 cm behind the knife head of the slit coating; (2) The distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 0.5 cm to 3 cm, and optionally, the distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 1 cm to 2 cm, and more optionally, the distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 0.8 cm to 1.2 cm; (3) The air knife pressure of the air knife process is 0.2Mpa to 4Mpa, and optionally, the air knife pressure of the air knife process is 1Mpa to 4Mpa, and further optionally, the air knife pressure of the air knife process is 2Mpa to 4Mpa; (4) The feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 mm / s to 80 mm / s, and optionally, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 mm / s to 45 mm / s, and further optionally, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 15 mm / s to 25 mm / s.

[0022] In one embodiment, the volume ratio of the first solvent to the second solvent is Y, the slit coating and the air knife process are performed sequentially, and 6≧Y≧1, optionally 4≧Y≧3.

[0023] In one embodiment thereof, the method for producing the perovskite film comprises: (1) The distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 0.5 cm to 3 cm, and optionally, the distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 0.5 cm to 2 cm, and more optionally, the distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 0.8 cm to 1.2 cm; (2) The air knife pressure of the air knife process is 0.3Mpa to 6Mpa, and optionally, the air knife pressure of the air knife process is 1Mpa to 6Mpa, and further optionally, the air knife pressure of the air knife process is 2Mpa to 4Mpa; (3) The feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 mm / s to 80 mm / s, and optionally, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 15 mm / s to 80 mm / s, and further optionally, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 25 mm / s to 55 mm / s.

[0024] A fourth aspect of the present application provides a power consuming device, the device comprising one or more of the perovskite solar cell according to the first aspect and a perovskite solar cell produced by the production method according to the third aspect. [Brief explanation of the drawings]

[0025] In order to more clearly explain the technical solutions of the embodiments of the present application, the following briefly introduces the drawings that need to be used in the embodiments of the present application. It is obvious that the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on the drawings without any creative efforts. [Figure 1] FIG. 1 is a structural schematic diagram of a perovskite solar cell fabricated in one embodiment of the present application. [Figure 2] FIG. 1 is a schematic diagram of the process steps for producing a perovskite film in one embodiment of the present application. [Figure 3] FIG. 1 is a coating morphology diagram after air knife crystallization (i.e., not annealed) in the process of producing a perovskite film in Example 1-1 of the present application. [Figure 4] FIG. 4 is a morphology diagram of a perovskite film produced by annealing the coating in FIG. 3. [Figure 5] FIG. 1 is a morphology diagram of the perovskite film produced in Example 2-1 of the present application. [Figure 6] 1 is a photograph of the perovskite film produced in Example 1-1 of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, with appropriate reference to the drawings, embodiments specifically disclosing the perovskite precursor solution, perovskite solar cell and manufacturing method thereof, and power consumption device of the present application will be described in detail. However, unnecessary detailed description may be omitted. For example, detailed description of well-known matters and redundant description of actually identical structures may be omitted. This is to avoid unnecessarily lengthening the following description and to facilitate understanding by those skilled in the art. Note that the drawings and the following description are provided to enable those skilled in the art to fully understand the present application, and are not intended to limit the subject matter described in the claims.

[0027] The "ranges" disclosed in this application are defined in the form of lower and upper limits, and a given range is defined by selecting one lower limit and one upper limit, and the selected lower and upper limits define the boundaries of the particular range. Such defined ranges may be inclusive or exclusive of the end values, and any combination is possible; i.e., any lower limit can be combined with any upper limit to form a single range. For example, if ranges of 60 to 120 and 80 to 110 are listed for a particular parameter, it is understood that ranges of 60 to 110 and 80 to 120 are also possible. Furthermore, if 1 and 2 are listed as minimum range values ​​and 3, 4, and 5 are listed as maximum range values, the ranges 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5 are all possible. In this application, unless otherwise specified, a numerical range "a to b" is a shorthand notation for any combination of real numbers a to b, where a and b are both real numbers. For example, the numerical range "0-5" represents that the present specification has already listed all real numbers between "0-5," and "0-5" is merely a shorthand representation of combinations of these numbers. Also, expressing a parameter as an integer ≧2 is equivalent to disclosing that this parameter is, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0028] Unless otherwise stated, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0029] Unless otherwise stated, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0030] Unless otherwise stated, all steps in this application may be performed in order, randomly, and in some cases, sequentially. For example, a description of a method including steps (a) and (b) means that the method may include steps (a) and (b) performed in order, or steps (b) and (a) performed in order. For example, a description of a method mentioned above that may further include step (c) means that step (c) may be added to the method in any order, e.g., the method may include steps (a), (b), and (c), or may include steps (a), (c), and (b), or may include steps (c), (a), and (b), etc.

[0031] The morphological characteristics relevant to this application can be obtained by equipment known in the art, including, but not limited to, scanning electron microscopes (SEMs) and atomic force microscopes (AFMs).

[0032] Currently, the most common process for manufacturing large-area perovskite films involves forming a wet film by slit coating, then using air knife purging or vacuum flash evaporation to remove large amounts of solvent from the wet film to achieve a solvent quenching effect, followed by annealing and crystallization to form the perovskite film. Vacuum flash evaporation, however, places high demands on equipment and is prone to shrinkage holes or pinholes in the resulting dry film, leading to reduced device performance. While other methods utilize air knife purging or vacuum flash evaporation to achieve solvent quenching, these methods rely primarily on vacuum flash evaporation, with air knife purging only as a secondary step. Therefore, it remains difficult to avoid the problems inherent in vacuum flash evaporation, and additional steps are required. While the traditional air knife purging process offers low cost and high production efficiency for large-area film manufacturing, it is difficult to produce high-quality (dense, flat, and uniform) perovskite films using the traditional air knife purging process.

[0033] Based on this, the present application has conducted extensive research and accumulated experience to find that the difficulty of forming high-quality perovskite films using the conventional air knife purging process is closely related to the composition of the solvent in the perovskite precursor solution formulation, thereby arriving at the technical solution of the present application.

[0034] A perovskite solar cell according to one example of the present application comprises a transparent electrode, a first functional layer, a perovskite film, a second functional layer, and a second electrode layer, which are stacked together, and the size distribution of the perovskite crystal grains in the perovskite film is ≧1.2 micrometers (μm).

[0035] Research has shown that the perovskite crystal grain size distribution of perovskite films produced by conventional air knife purging processes is generally smaller than 1 μm, while the perovskite crystal grain size distribution of the perovskite films of the present application is ≧1.2 μm, which is difficult to achieve by conventional processes, and significantly improves the flatness of the corresponding perovskite films, further effectively improving the cell efficiency.

[0036] As can be seen, the size distribution of perovskite crystal grains in a perovskite film refers to the particle size corresponding to when the cumulative particle size distribution percentage in the sample reaches 50%, which is the size where the range of particle sizes in a single perovskite crystal grain is the widest when accumulated.

[0037] In some of these examples, the size distribution of the perovskite crystal grains in the perovskite film is ≧2 μm.Furthermore, the size distribution of the perovskite crystal grains in the perovskite film is 2 μm to 3 μm.

[0038] In some cases, the surface of the perovskite film exhibits a white mist appearance. Due to the large number of large-sized perovskite crystal grains in the perovskite film of the present application, obvious scattering phenomenon can occur, and the surface exhibits a white mist appearance, thus indicating fewer crystal grain defects, which can improve the current and open circuit voltage, and further improve the performance and service life of the perovskite assembly.

[0039] Another example of the present application provides a perovskite precursor solution, the composition of which includes a perovskite precursor material and a solvent, the solvent including a first solvent and a second solvent; (1) the boiling point of the first solvent is lower than the boiling point of the second solvent; (2) The saturated vapor pressure of the first solvent is higher than the saturated vapor pressure of the second solvent.

[0040] Research has found that the crystalline quality of perovskite films is significantly related to the process window of the perovskite precursor solution. According to perovskite crystal growth theory, achieving high-quality perovskite films requires rapid and explosive nucleation within a short period of time. That is, when the system contains an adequate amount of nuclei, the solvent must be rapidly extracted to allow the existing seed crystals to grow larger, preventing the formation of additional nuclei and reducing dendrite formation. (In perovskite devices, dense, flat, large crystal grains provide excellent performance, but too many nuclei can lead to the formation of disordered dendrites. Because solute in the solution is finite, the conversion of solute into nuclei reduces the components available for nuclei growth, making it difficult to form large crystal grains.) If the process window in the system is too short and solvent quenching is not performed, too many nuclei will result in the formation of dendrites, resulting in poor crystalline quality of the perovskite film. If the process window is too long, solvent quenching is required. Therefore, the process window needs to be rationally adjusted, and the process window of the perovskite precursor solution can be adjusted by adjusting the occupancy of solvents with different boiling points and / or saturated vapor pressures. Therefore, the present application employs and blends two solvents with different boiling points and / or different saturated vapor pressures to adjust the process window, which is further adapted to the air knife process and enables the production of high-quality perovskite films.

[0041] Furthermore, the perovskite precursor solution is actually a kind of colloid, in which the perovskite precursor material and the solvent exist in the form of a complex, so the boiling point and saturated vapor pressure of the solvent directly affect the rate of crystal nucleation.

[0042] In some examples, the absolute value of the difference between the boiling points of the first solvent and the second solvent is 30 or more. Furthermore, the absolute value of the difference between the boiling points of the first solvent and the second solvent is 50 to 150. Specifically, the absolute value of the difference between the boiling points of the first solvent and the second solvent includes, but is not limited to, 50, 55, 60, 65, 67.68, 70, 71.4, 75, 77.5, 80, 85, 90, 95, 100, 105, 107.4, 110, 115, 120, 121.4, 125, 130, 135, 140, 145, 150, or a range between any two of the aforementioned values. By rationally controlling the difference between the boiling points of the first solvent and the second solvent, higher energy conversion efficiency can be achieved.

[0043] In some examples, the saturated vapor pressure of the first solvent is 8 times or more the saturated vapor pressure of the second solvent. Furthermore, the multiple of the saturated vapor pressure of the first solvent to the saturated vapor pressure of the second solvent is 10 to 200 times. Specifically, the multiple of the saturated vapor pressure of the first solvent to the saturated vapor pressure of the second solvent includes, but is not limited to, 10, 15, 20, 25, 30, 35, 40, 45, 50, 80, 100, 120, 150, 160, 170, 180, 200, and 300. By rationally controlling the multiple of the saturated vapor pressure of the first solvent to the saturated vapor pressure of the second solvent, higher energy conversion efficiency can be achieved.

[0044] In some examples, the boiling point of the first solvent is 70 degrees Celsius (°C) to 160°C. Specifically, the boiling point of the first solvent includes, but is not limited to, 70°C, 75°C, 80°C, 81.6°C, 85°C, 90°C, 95°C, 100°C, 101.32°C, 105°C, 110°C, 115°C, 120°C, 124.5°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C, 155°C, 160°C, or a range between any two of the aforementioned values. Furthermore, the boiling point of the first solvent is 75°C to 155°C.

[0045] In some examples, the saturated vapor pressure of the first solvent is greater than 2 millimeters of mercury (mm Hg) at 20° C. Furthermore, the saturated vapor pressure of the first solvent at 20° C. is 2.5 mm Hg to 200 mm Hg. Specifically, the saturated vapor pressure of the first solvent at 20° C. includes, but is not limited to, 2.5 mm Hg, 5 mm Hg, 7 mm Hg, 10 mm Hg, 15 mm Hg, 20 mm Hg, 25 mm Hg, 30 mm Hg, 50 mm Hg, 70 mm Hg, 80 mm Hg, 100 mm Hg, 120 mm Hg, 130 mm Hg, 150 mm Hg, 170 mm Hg, and 200 mm Hg.

[0046] In some examples, the boiling point of the second solvent is 130°C to 220°C. Specifically, the boiling point of the second solvent includes, but is not limited to, 130°C, 135°C, 140°C, 145°C, 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C, 200°C, 205°C, 210°C, 215°C, 220°C, or a range between any two of the aforementioned values. Furthermore, the boiling point of the second solvent is 150°C to 210°C.

[0047] In some examples, the saturated vapor pressure of the second solvent is 3 mm Hg or less at 20° C. Furthermore, the saturated vapor pressure of the second solvent is 0.2 mm Hg to 3 mm Hg at 20° C. Specifically, the saturated vapor pressure of the second solvent at 20°C includes, but is not limited to, 0.2mmHg, 0.3mmHg, 0.4mmHg, 0.5mmHg, 0.6mmHg, 0.7mmHg, 0.8mmHg, 0.9mmHg, 1mmHg, 1.1mmHg, 1.2mmHg, 1.3mmHg, 1.4mmHg, 1.5mmHg, 1.6mmHg, 1.7mmHg, 1.8mmHg, 1.9mmHg, 2mmHg, 2.1mmHg, 2.2mmHg, 2.3mmHg, 2.4mmHg, 2.5mmHg, 2.6mmHg, 2.7mmHg, 2.8mmHg, 2.9mmHg, 3mmHg, or a range between any two of the aforementioned values.

[0048] Furthermore, the higher the proportion of the high-boiling point, low-saturation vapor pressure solvent (second solvent), the slower the crystal nucleation and the longer the process window. However, if the proportion of the high-boiling point, low-saturation vapor pressure solvent (second solvent) is too high, the air pressure required for the air knife process also increases, making it difficult to perform uniform solvent quenching. Therefore, it is necessary to balance the two as needed.

[0049] In some examples, the volume ratio of the first solvent to the second solvent is Y, and 20≧Y≧1. Specifically, the value of Y includes, but is not limited to, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or a range between any two of the aforementioned values. Rational control of the volume ratio of the first solvent to the second solvent is beneficial to the formation of a uniform perovskite film and achieves higher energy conversion efficiency.

[0050] In some examples, the solids content of the perovskite precursor solution is 10% to 40%. Specifically, the solids content of the perovskite precursor solution includes, but is not limited to, 10%, 15%, 18%, 20%, 25%, 30%, 35%, 40%, or a range between any two of the aforementioned values. Furthermore, the solids content of the perovskite precursor solution is 10% to 25%. By rationally controlling the solids content of the perovskite precursor solution, higher energy conversion efficiency can be achieved.

[0051] Specifically, the first solvent includes one or more of acetonitrile, dioxane, ethylene glycol monomethyl ether, and N,N-dimethylformamide (DMF).

[0052] Specifically, the second solvent includes one or more of N,N-dimethylformamide (DMF), N,N-diethylacetamide (DMAC), N-methylpyrrolidone (NMP), dimethylsulfoxide (DMSO), and gamma-butyrolactone (GBL).

[0053] Specifically, the perovskite precursor material may be a conventional material type in the art, and may have a general structural formula of, but not limited to, ABX3 or A2CDX6, where A is a monovalent cation, B is a divalent metal cation, C and D are monovalent and trivalent metal cations, respectively, and X is a monovalent anion.

[0054] Non-limiting examples of A include Cs + , K. + , Rb + , monovalent amine-based cations, and monovalent amidine-based cations.

[0055] B may be, but is not limited to, Pb 2+ , Sn 2+ , Fe 2+ , Mn 2+ , Ni 2+ , Ge 2+ , Co 2+ and Sb 2+ It includes one or more of the following.

[0056] Without limitation, C can be Cs + , Ag + , K. + and Ru + It includes one or more of the following.

[0057] Non-limiting examples of D include Bi 3+ , Ni 3+ , Fe 3+ and Cu 3+ It includes one or more of the following.

[0058] Non-limiting examples of X include I - , Br - and Cl - It includes one or more of the following.

[0059] Another example of the present application provides a method for manufacturing a perovskite solar cell, the method comprising: Producing a first functional layer on the surface of the transparent electrode; producing a perovskite film on a surface of the first functional layer; fabricating a second functional layer on a surface of the perovskite film; and forming a second electrode layer on the surface of the second functional layer, producing a perovskite film on a surface of the first functional layer, applying a perovskite precursor solution on the surface of the first functional layer by slit coating, and quenching a solvent in the perovskite precursor solution by an air knife process to form an intermediate film, wherein the perovskite precursor solution is the perovskite precursor solution described above; and annealing the intermediate film to produce the perovskite film.

[0060] The above manufacturing method employs the above perovskite precursor solution and, in combination, employs an air knife process to quench the solvent in the perovskite precursor solution, and by controlling the solvent blending and the air knife process, can synergistically realize the production of high-quality perovskite films, and is more suitable for industrial production of large-area perovskite films.

[0061] Furthermore, to achieve better synergistic blending with the solvent and produce high-quality perovskite films, it is necessary to control the uniformity of the air knife blown during the air knife process. The uniformity of the air knife blown is mainly affected by the following factors: whether it moves together with the slit coating knife head (or moves independently), the installation position of the air knife relative to the slit coating knife head (if the air knife moves together with the slit coating knife head), the distance from the air knife to the coating reference surface, the air pressure, and the air knife feed rate.

[0062] The air knife process can be divided into two types. The first type is where the slit coating and air knife process are performed synchronously, i.e., the slit coating knife head and the air knife of the air knife process move together, with the air knife stationary relative to the slit coating knife head and the air knife positioned a certain distance behind the slit coating knife head. The second type is where the slit coating and air knife process are performed sequentially, i.e., after slit coating is completed, an air knife process purge is performed, and the slit coating knife head and the air knife of the air knife process move independently. Research has revealed that there are differences in the solvent formulation requirements of the two types of processes to achieve the production of high-quality perovskite films.

[0063] In some examples, the volume ratio of the first solvent to the second solvent is Y, the slit coating and air knife processes are performed synchronously, and 20≧Y≧6. Specifically, the value of Y includes, but is not limited to, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or a range between any two of the aforementioned values. Furthermore, Y is 6 to 15. When the slit coating and air knife processes are performed synchronously, the required time for the process window is short (generally less than 10 seconds), and under the above condition of Y, solvent quenching can be rapidly achieved and higher energy conversion efficiency can be achieved.

[0064] Furthermore, when the slit coating and the air knife process are performed synchronously, the settings of the parameters satisfy the following:

[0065] In some examples, the air knife of the air knife process is located 5 centimeters (cm) to 30 cm behind the knife head of the slit coating along the coating direction of the slit coating. Specifically, the position of the air knife of the air knife process behind the knife head of the slit coating includes, but is not limited to, 5 cm, 10 cm, 15 cm, 20 cm, 25 cm, 30 cm, or a range between any two of the aforementioned values. Furthermore, the air knife of the air knife process is located 10 cm to 20 cm behind the knife head of the slit coating. By rationally controlling these process parameters, higher energy conversion efficiency can be achieved.

[0066] In some examples, the distance between the knife head of the air knife and the surface of the first functional layer in the air knife process is 0.5 cm to 3 cm. Specifically, the distance between the knife head of the air knife and the surface of the first functional layer in the air knife process is 0.5 cm, 0.8 cm, 1 cm, 1.2 cm, 1.5 cm, 2 cm, 2.5 cm, 3 cm, or a range between any two of the aforementioned values, but is not limited to these. Furthermore, the distance between the knife head of the air knife and the surface of the first functional layer in the air knife process is 1 cm to 2 cm. Furthermore, the distance between the knife head of the air knife and the surface of the first functional layer in the air knife process is 0.8 cm to 1.2 cm. By rationally controlling these process parameters, higher energy conversion efficiency can be achieved.

[0067] In some examples, the angle between the air knife of the air knife process and the surface of the first functional layer is not particularly limited and can be set according to the equipment, for example, it can generally be set to 90°±30°.

[0068] In some examples, the air knife pressure of the air knife process is 0.2 megapascals (Mpa) to 4 Mpa. Specifically, the air knife pressure of the air knife process includes, but is not limited to, 0.2 Mpa, 0.5 Mpa, 1 Mpa, 1.5 Mpa, 2 Mpa, 2.5 Mpa, 3 Mpa, 3.5 Mpa, 4 Mpa, or a range between any two of the aforementioned values. Furthermore, the air knife pressure of the air knife process is 1 Mpa to 4 Mpa. Furthermore, the air knife pressure of the air knife process is 2 Mpa to 4 Mpa. By rationally controlling these process parameters, higher energy conversion efficiency can be achieved.

[0069] In some examples, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 millimeters per second (mm / s) to 80 mm / s. Specifically, the feed speed of the air knife in the air knife process and the knife head in the slit coating includes, but is not limited to, 5 mm / s, 10 mm / s, 15 mm / s, 20 mm / s, 25 mm / s, 30 mm / s, 35 mm / s, 40 mm / s, 45 mm / s, 50 mm / s, 55 mm / s, 60 mm / s, 65 mm / s, 70 mm / s, 75 mm / s, 80 mm / s, or a range between any two of the aforementioned values. Furthermore, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 mm / s to 45 mm / s. Furthermore, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 15 mm / s to 25 mm / s. By rationally controlling these process parameters, higher energy conversion efficiency can be achieved.

[0070] In some examples, the volume ratio of the first solvent to the second solvent is Y, the slit coating and air knife processes are performed sequentially, and 6≧Y≧1. Specifically, the value of Y includes, but is not limited to, 1, 2, 3, 4, 5, 6, or a range between any two of the aforementioned values. Furthermore, 4≧Y≧3. When the slit coating and air knife processes are performed sequentially, the required time for the process window is long, and under the above Y conditions, it is possible to ensure that the perovskite precursor does not form dendrites too quickly, and to achieve higher energy conversion efficiency.

[0071] Furthermore, when the slit coating and air knife process are carried out in sequence, the settings of each parameter satisfy the following:

[0072] In some examples, the distance between the knife head of the air knife and the coating reference surface is 0.5 cm to 3 cm. Specifically, the distance between the knife head of the air knife and the surface of the first functional layer is 0.5 cm, 0.8 cm, 1 cm, 1.2 cm, 1.5 cm, 2 cm, 2.5 cm, 3 cm, or a range between any two of the aforementioned values, but is not limited to these. Furthermore, the distance between the knife head of the air knife and the surface of the first functional layer is 0.5 cm to 2 cm. Furthermore, the distance between the knife head of the air knife and the surface of the first functional layer is 0.8 cm to 1.2 cm. By rationally controlling these process parameters, higher energy conversion efficiency can be achieved.

[0073] In some examples, the angle between the air knife of the air knife process and the surface of the first functional layer is not particularly limited and can be set according to the equipment, for example, it can generally be set to 90°±30°.

[0074] In some examples, the air knife pressure of the air knife process is 0.3 MPa to 6 MPa. Specifically, the air knife pressure of the air knife process includes, but is not limited to, 0.3 MPa, 0.5 MPa, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa, 3 MPa, 3.5 MPa, 4 MPa, 4.5 MPa, 5 MPa, 5.5 MPa, 6 MPa, or a range between any two of the aforementioned values. Furthermore, the air knife pressure of the air knife process is 1 MPa to 6 MPa. Furthermore, the air knife pressure of the air knife process is 2 MPa to 4 MPa. By rationally controlling these process parameters, higher energy conversion efficiency can be achieved.

[0075] In some examples, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 mm / s to 80 mm / s. Specifically, the feed speed of the air knife in the air knife process and the knife head in the slit coating includes, but is not limited to, 5 mm / s, 10 mm / s, 15 mm / s, 20 mm / s, 25 mm / s, 30 mm / s, 35 mm / s, 40 mm / s, 45 mm / s, 50 mm / s, 55 mm / s, 60 mm / s, 65 mm / s, 70 mm / s, 75 mm / s, 80 mm / s, or a range between any two of the aforementioned values. Furthermore, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 15 mm / s to 80 mm / s. Furthermore, the feed speed of the air knife in the air knife process and the knife head in the slit coating is 25 mm / s to 55 mm / s. By rationally controlling these process parameters, higher energy conversion efficiency can be achieved.

[0076] As can be seen, perovskite solar cells include cis-type and trans-type solar cells, and as shown in FIG. 1 , include a first electrode 500, an electron transport layer or hole transport layer 400, a perovskite body layer 300, a hole transport layer or electron transport layer 200, and a second electrode 100, which are sequentially stacked on a glass substrate 600. As a cis-type perovskite solar cell, it includes a transparent electrode, and an electron transport layer, a perovskite body layer, a hole transport layer, and a second electrode, which are sequentially stacked on the transparent electrode. As a trans-type perovskite solar cell, it includes a transparent electrode, and a hole transport layer, a perovskite body layer, an electron transport layer, and a second electrode, which are sequentially stacked on the transparent electrode. Here, the transparent electrode is used for light incidence.

[0077] Materials for the electron transport layer include, but are not limited to, imide compounds, quinone compounds, fullerene and its derivatives, methoxytriphenylamine-fluoroformamidine (OMeTPA-FA), calcium titanate (CaTiO3), lithium fluoride (LiF), calcium fluoride (CaF2), poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid (PEDOT:PSS), poly3-hexylthiophene (P3HT), triptycene-based triphenylamine (H101), 3,4-ethylenedioxythiophene-methyl The material may be one or more of the following materials and derivatives: edoxotriphenylamine (EDOT-OMeTPA), N-(4-aniline)carbazole-spirobifluorene (CzPAF-SBF), polythiophene, metal oxide (wherein the metal element is selected from Mg, Ni, Cd, Zn, In, Pb, Mo, W, Sb, Bi, Cu, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, or Cr), silicon oxide (SiO2), strontium titanate (SrTiO3), cuprous thiocyanate (CuSCN), and derivatives thereof.

[0078] The hole transport layer may be formed from, but is not limited to, 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), polytriarylamine (PTAA), NiO x The material may be one or more of materials capable of transporting holes and blocking electrons, such as poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), WO3, and derivatives thereof.

[0079] The material of the second electrode layer may be, but is not limited to, an organic or inorganic conductive material, or a mixture of both in various ratios, such as metallic conductive materials such as gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), bismuth (Bi), platinum (Pt), magnesium (Mg), or mixtures thereof, or conductive oxide glass such as FTO, ITO, or aluminum-doped zinc oxide (AZO).

[0080] Non-limiting examples of the material for the transparent electrode include FTO, ITO, AZO, BZO, and IZO.

[0081] The transparent electrode further includes, but is not limited to, a substrate layer, which is a flexible substrate layer made of an organic polymer material, such as polyvinyl alcohol (PVA), polyester (PET), polyimide (PI), polyethylene naphthalate (PEN), or polydimethylsiloxane (PDMS), which may be mixed in various ratios.

[0082] Specifically, the perovskite solar cell is a cis-type, and the manufacturing method thereof includes: Step 1: Etching, cleaning and drying the transparent electrode; Step 2: fabricating an electron transport layer on the transparent electrode; Step 3 of preparing the perovskite film on an electron transport layer; Step 4: fabricating a hole transport layer on the perovskite layer; and step 5 of fabricating a second electrode layer on the hole transport layer.

[0083] Specifically, the perovskite solar cell is a transformer type, and the manufacturing method thereof includes: Step 1: Etching, cleaning and drying the transparent electrode; Step 2: fabricating a hole transport layer on the transparent electrode; Step 3 of preparing the perovskite film on a hole transport layer; Step 4: fabricating an electron transport layer on the perovskite layer; and b. step 5 of fabricating a second electrode layer on the electron transport layer.

[0084] The present application provides a power consumption device, which includes one or more of the above-described perovskite solar cell and a perovskite solar cell manufactured by the above-described method for manufacturing a solar cell.

[0085] In some embodiments, the solar cell may be used as a power source for a power consuming device or as an energy storage unit for a power consuming device.

[0086] Furthermore, the power consuming devices may include, but are not limited to, mobile devices such as mobile phones and laptops, electric vehicles, electric trains, ships and satellites, energy storage systems, etc. Here, the electric vehicles may be pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, etc.

[0087] Another example of a power consuming device may be a mobile phone, a tablet computer, a laptop, or the like.

[0088] Examples of the present application are described below. The examples described below are illustrative and are intended only to interpret the present application, and should not be understood as limitations on the present application. Specific techniques or conditions not described in the examples are carried out in accordance with the techniques, conditions, or product specifications described in documents within the field. Reagents or equipment used without a manufacturer's name are all commercially available ordinary products.

[0089] Manufacturing Example The specifications of the manufactured perovskite solar cells are 300mm x 300mm.

[0090] [First electrode assembly preparation] 1) A set of FTO conductive glass with a specification of 300mm*300mm was taken, and P1 was etched using an infrared laser. The width of P1 was about 30μm. The entire glass was divided into 44 sub-cells along the length, and the series resistance of each sub-cell was greater than 10MΩ. The welding area for the assembly was 10mm above and below.

[0091] 2) After etching, the surface of the conductive glass was washed twice with acetone and isopropanol, immersed in deionized water and ultrasonically treated for 10 minutes, dried in a blower dryer, and then placed in a drying room (humidity less than 2%) to form the first electrode.

[0092] [Fabrication of assembly hole transport layer: nickel oxide layer] 3) After cleaning, the conductive glass is placed in a magnetron sputtering chamber to form a hole transport layer of NiO. x The thickness of the nickel oxide layer is about 15 nm.

[0093] [Fabrication of Assembly Perovskite Films] 4) According to Tables 1 and 2 below, perovskite precursor solutions with different solvent blend ratios and solvent types were prepared. The solute was 1.1M FA. 0.95 Cs 0.05 It is PbI3.

[0094] 5) The above perovskite precursor solution was coated by slit coating, and a hole transport layer, NiO x A perovskite wet film was formed on the surface of the NiOx preform 800, and then solvent quenching was performed using two different air knife processes according to the air knife process parameters in Tables 1 and 2 (Table 1: air knife purging while coating; Table 2: air knife purging after coating). Finally, the perovskite film was annealed at 110°C for 20 minutes to obtain a perovskite film, i.e., a perovskite absorber layer. This process is shown in Figure 2. The hole transport layer NiOx preform 800 was placed on the surface of the coating stage 700, and the perovskite precursor solution was coated using a slit coating head Q1 to form a perovskite wet film, and then solvent quenching was performed using an air knife Q2.

[0095] [Fabrication of Assembly Charge Transport Layer] 6) After the perovskite absorber layer is fabricated, the substrate is placed in a vacuum thermal evaporation apparatus. -4 The vacuum was drawn to 100 Pa, and 30 nm of C60 and 8 nm of BCP were deposited as the assembly charge transport layer.

[0096] [Preparation of second electrode assembly] 7) After depositing the charge transport layer in the vacuum thermal evaporation equipment, subsequently deposit 10 nm of Ag on its surface, and then expose it to the atmosphere and remove it. P2 is laser-etched, the width of P2 is 150 μm, and the depth is etched to the FTO layer. The distance between P2 and P1 is 20 μm. Then the substrate is put back into the evaporation equipment and 4*10 -4 After evacuation to 100 Pa, a single layer of Ag was subsequently deposited to a thickness of about 80 nm.

[0097] 8) After cooling, it is exposed to the atmosphere and removed, and P3 is etched with a green laser for P seconds. The width of P3 is 15 μm, and the etching depth reaches the FTO layer. The distance between P3 and P2 is 20 μm (the positions of the etching lines are P1 / P2 / P3 in order).

[0098] 9) The assembly was then infrared trimmed, i.e., etched 10 mm on each side of the assembly.

[0099] Test Example (1) Performance testing of perovskite solar cell assemblies Performance tests were carried out on the perovskite solar cell assemblies manufactured in the examples and comparative examples.

[0100] 1000W / m 2 The energy conversion efficiency of the assembly was tested using a solar simulator. Specifically, sunlight was used at room temperature and pressure to simulate a standard AM1.5G light source, and a 4-channel digital source meter (Keithley 2440) was used to measure the current-voltage characteristic curve of the assembly under light irradiation. The open-circuit voltage Voc, short-circuit current density Jsc, and fill factor FF of the assembly were obtained to determine the power conversion efficiency PCE of the assembly, and the results were converted into a single cell and entered into Tables 1 and 2 below.

[0101] [Table 1]

[0102] [Table 2]

[0103] [Table 3]

[0104] 2) In Tables 1 and 2, Y = first solvent / second solvent (volume ratio).

[0105] 3) Distance X1 = distance of the air knife of the air knife process behind the knife head of the slit coating along the coating direction.

[0106] 4) Distance X2 = the distance between the knife head of the air knife in the air knife process and the coating reference surface.

[0107] 5) Air knife angle = the angle between the air knife in the air knife process and the coating reference surface.

[0108] (2) Morphological detection The detection method is scanning electron microscopy (SEM).

[0109] The detection samples are Examples 1-1 and 2-1.

[0110] The detection results are shown in Figures 3 to 5. As can be seen from these, the samples produced in Examples 1-1 and 2-1 have microscopically dense crystal grains, meaning no gaps, few grain boundaries, and few defects. The size distribution of the main crystal grains is 1.2 μm or more, and can reach a maximum of 2.12 μm, and has excellent flatness.

[0111] In addition, a photograph of the sample of Example 1-1 is shown in FIG. 6, and it can be seen that the surface is white and misty.

[0112] It should be noted that the present application is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any embodiment that has substantially the same configuration as the technical idea and achieves the same effects within the scope of the technical solution of the present application is included within the technical scope of the present application. In addition, various modifications that a person skilled in the art can make to the embodiments without departing from the spirit of the present application, and other methods configured by combining some of the components of the embodiments, are also included within the scope of the present application. [Explanation of symbols]

[0113] 100—second electrode, 200—hole transport layer or electron transport layer, 300—perovskite body layer, 400—electron transport layer or hole transport layer, 500—first electrode, 600—glass substrate, 700—coating stage, 800—preform comprising hole transport layer NiOx, Q1—slit coating head, Q2—air knife.

Claims

1. 1. A perovskite solar cell comprising a transparent electrode, a first functional layer, a perovskite film, a second functional layer, and a second electrode layer, which are stacked together, wherein the size distribution of perovskite crystal grains in the perovskite film is ≧1.2 μm.

2. 2. The perovskite solar cell of claim 1, wherein the size distribution of the perovskite crystal grains in the perovskite film is ≥ 2 μm.

3. 3. The perovskite solar cell according to claim 2, wherein the size distribution of the perovskite crystal grains in the perovskite film is 2 μm to 3 μm.

4. a perovskite precursor solution, the composition of which comprises a perovskite precursor material and a solvent, the solvent comprising a first solvent and a second solvent; (1) the boiling point of the first solvent is lower than the boiling point of the second solvent; (2) The saturated vapor pressure of the first solvent is greater than the saturated vapor pressure of the second solvent.

5. The first solvent and the second solvent are (1) the absolute value of the difference between the boiling point of the first solvent and the boiling point of the second solvent is ≧30; (2) The saturated vapor pressure of the first solvent is eight times or more the saturated vapor pressure of the second solvent.

6. The first solvent is (1) The boiling point is 70 to 160°C; (2) A saturated vapor pressure of the perovskite precursor solution is greater than 2 mm Hg at 20°C.

7. The second solvent is (1) The boiling point is 130 to 220°C; (2) The perovskite precursor solution according to any one of claims 4 to 6, which satisfies one or more of the following: (1) the saturated vapor pressure is 3 mm Hg or less under a condition of 20°C;

8. 8. The perovskite precursor solution according to claim 4, wherein a volume ratio of the first solvent to the second solvent is Y, and 20≧Y≧1.

9. 9. The perovskite precursor solution according to claim 4, wherein the solids content of the perovskite precursor solution is 10% to 40%.

10. The perovskite precursor solution according to any one of claims 4 to 9, wherein the first solvent comprises one or more of acetonitrile, dioxane, ethylene glycol monomethyl ether, and N,N-dimethylformamide.

11. The perovskite precursor solution according to any one of claims 4 to 10, wherein the second solvent comprises one or more of N,N-dimethylformamide, N,N-diethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, and γ-butyrolactone.

12. The general structural formula of the perovskite precursor material is ABX ３ or A ２ CDX ６ 12. The perovskite precursor solution of claim 4, wherein A is a monovalent cation, B is a divalent metal cation, C and D are monovalent and trivalent metal cations, respectively, and X is a monovalent anion.

13. (1) A is Cs ＋ , K. ＋ , Rb ＋ , monovalent amine-based cations, and monovalent amidine-based cations; (2) B is Pb ２＋ , Sn ２＋ , Fe ２＋ , Mn ２＋ , Ni ２＋ , Ge ２＋ , Co ２＋ and Sb ２＋ and (3) C is Cs ＋ , Ag ＋ , K. ＋ and Ru ＋ and (4) D is Bi ３＋ , Ni ３＋ , Fe ３＋ and Cu ３＋ and (5) X is I － ,Br － and Cl － The perovskite precursor solution according to any one of claims 4 to 12, which satisfies one or more of the following:

14. A method for manufacturing a perovskite solar cell, comprising: Producing a first functional layer on the surface of the transparent electrode; producing a perovskite film on a surface of the first functional layer; fabricating a second functional layer on a surface of the perovskite film; and forming a second electrode layer on the surface of the second functional layer, producing a perovskite film on a surface of the first functional layer, applying a perovskite precursor solution on the surface of the first functional layer by slit coating, and quenching a solvent in the perovskite precursor solution by an air knife process to form an intermediate film, wherein the perovskite precursor solution is the perovskite precursor solution according to any one of claims 4 to 13; and annealing the intermediate state film to produce the perovskite film.

15. 15. The method for producing a perovskite solar cell according to claim 14, wherein a volume ratio of the first solvent to the second solvent is Y, the slit coating and air knife processes are performed synchronously, and 20≧Y≧6.

16. (1) along the coating direction of the slit coating, the air knife of the air knife process is located 5 cm to 30 cm behind the knife head of the slit coating; (2) The distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 0.5 cm to 3 cm; (3) the air knife pressure of the air knife process is 0.2 MPa to 4 MPa; (4) The method for producing a perovskite solar cell according to claim 15, wherein the feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 mm / s to 80 mm / s.

17. 15. The method for producing a perovskite solar cell according to claim 14, wherein a volume ratio of the first solvent to the second solvent is Y, the slit coating and air knife process are performed sequentially, and 6≧Y≧1.

18. (1) The distance between the knife head of the air knife in the air knife process and the surface of the first functional layer is 0.5 cm to 3 cm; (2) the air knife pressure of the air knife process is 0.3 MPa to 6 MPa; (3) The feed speed of the air knife in the air knife process and the knife head in the slit coating is 5 mm / s to 80 mm / s.

19. A power consumption device comprising one or more of the perovskite solar cell according to any one of claims 1 to 3 and a perovskite solar cell produced by the production method according to any one of claims 14 to 18.

Images