Apparatus and method for preparing large-area perovskite thin film by confined hot pressing

Abstract

This invention discloses an apparatus and method for preparing large-area perovskite thin films using confined hot pressing. The apparatus includes a working platform, a hot pressing assembly, and a transmission device. The working platform is used to hold the substrate. The platform has a surrounding enclosure structure and a bottom with heating functionality. The surrounding enclosure structure ensures that the perovskite precursor solution does not flow out of the platform and pollute the environment. The top cylindrical structure of the hot pressing assembly is used to inject the perovskite precursor solution. The bottom consists of high-density small channels, all connected to the top injection structure. The hot pressing assembly has a global heating system, enabling rapid drying of the perovskite wet film to form a perovskite thin film. The transmission device is used to move the hot pressing assembly, precisely controlling the distance between the hot pressing assembly and the substrate on the working platform, thereby forming perovskite thin films of different thicknesses. This apparatus has a simple structure, is easy to operate, has low requirements for precision and airtightness, and can prepare high-quality large-area perovskite thin films.

Description

Technical Field

[0001] This invention perovskite solar cells, specifically relating to an apparatus and method for preparing large-area perovskite thin films by confined hot pressing. Background Technology

[0002] With the rapid growth of the global population and the rapid development of the economy, energy demand has increased dramatically. However, most energy consumption currently comes from fossil fuels, causing serious environmental pollution and the greenhouse effect. Therefore, the development and effective utilization of renewable and clean energy sources such as solar, wind, and geothermal energy is urgent. Among them, solar energy is an inexhaustible clean energy source, and solar cells are one of the effective means of utilizing solar energy. In recent years, perovskite solar cells have attracted much attention in the photovoltaic research field due to their advantages such as high efficiency, low cost, and the ability to be fabricated into flexible devices. They have become a new generation of solar cells comparable to silicon crystalline cells. Compared with crystalline silicon solar cells, researchers have found that perovskite solar cells have advantages such as a wider light absorption range, extremely high molar absorption coefficient, longer electron and hole diffusion lengths, and the ability to be synthesized in the liquid phase. Furthermore, the band gap of perovskite materials can be changed by adjusting their chemical composition, thereby obtaining thin films with different light absorption regions and tunable colors, making the application range of perovskite solar cells wider.

[0003] Currently, in the laboratory stage, the main method for fabricating perovskite solar cells is spin coating. However, this method is difficult to integrate with industrial production, resulting in significant material waste and high device costs. Newly developed methods such as spraying, scraping, and slot coating have strict requirements for equipment precision and environmental sealing, and are also complex and costly, making them unsuitable for the industrial production of large-area perovskite solar cells. Summary of the Invention

[0004] To address the aforementioned problems, this work provides an apparatus and method for preparing large-area perovskite thin films using confined hot pressing. This apparatus and method can yield high-quality large-area perovskite thin films that are large in area, dense, uniform, flat, and have controllable thickness.

[0005] A first aspect of this invention provides a method for preparing large-area perovskite thin films by confined hot pressing, comprising the following steps:

[0006] Step 1: Prepare the perovskite precursor solution;

[0007] Step 2: Operate the transmission device to control the hot pressing assembly to maintain a certain distance from the substrate on the work platform;

[0008] Step 3: Inject the perovskite precursor solution into the top of the hot-pressing assembly and use a booster to push the perovskite precursor solution into each channel.

[0009] Step 4: Once the perovskite precursor solution flows out from the bottom channels of the hot-pressing assembly and connects to form a dense, uniform, and flat perovskite wet film that covers the substrate, stop the injection process.

[0010] Step 5: Finely adjust the transmission device according to the required perovskite film thickness to control the distance between the hot pressing assembly and the substrate;

[0011] Step 6: Turn on the global heating system of the hot pressing assembly to dry the perovskite wet film and form a perovskite thin film, and slowly raise the hot pressing mechanism to allow the solvent in the perovskite precursor solution to evaporate.

[0012] Step 7: Turn on the heating device of the work platform to anneal the formed perovskite film.

[0013] Furthermore, the perovskite precursor solution composition includes MAPbI3, MAPbBr3, MAPbCl3, and MAPbI 3- x Br x MAPbI 3-x Cl x MA y FA 1-y PbI3, MA y FA 1-y PbI 3-x Cl x MA y FA 1-y PbI 3-x Br x Any one of CsSnxPb1-xI3, CsPbI3, CsSnI3, and CsPbBr3.

[0014] Furthermore, the concentration of the prepared perovskite precursor solution is 1-2.5 mol / mL.

[0015] A second aspect of the present invention provides an apparatus for preparing large-area perovskite thin films by confined hot pressing, applied to the method provided in the first aspect of the present invention, comprising:

[0016] The working platform is used to place the substrate. It integrates a vacuum adsorption device to ensure that the substrate is fixed and does not move, and can perform annealing treatment on the perovskite film.

[0017] Hot pressing assembly, used to hot press perovskite thin films onto a substrate surface;

[0018] A transmission device is used to move the hot pressing assembly and control the distance between the hot pressing assembly and the substrate on the working platform, thereby forming perovskite films of different thicknesses.

[0019] Furthermore, the equipment structure has a hot pressing assembly on top and a working base below, with the two in a parallel state, and the distance between them is controlled by a rear transmission device.

[0020] Furthermore, the hot pressing assembly of the device includes a perovskite precursor solution injection structure and integrates a global heating system.

[0021] Furthermore, the bottom of the hot pressing assembly of the device is composed of high-density small channels with a microstructure, which allows the perovskite precursor solution injected from the top to flow out and connect, forming a dense, uniform, and flat perovskite wet film.

[0022] Furthermore, the hot pressing assembly of the device has independent opening and closing functions for each channel at the bottom, which can open and close a portion of the channels according to the size of the substrate to prevent the perovskite precursor solution from flowing out and contaminating the working platform.

[0023] Furthermore, the working platform of the device is used to place the substrate. It integrates a vacuum adsorption device to ensure that the substrate is fixed and does not move. The working platform has a surrounding fence structure and a heating function at the bottom, which can perform annealing treatment on the perovskite film. The surrounding fence structure can also ensure that the perovskite precursor solution does not flow out of the platform and pollute the environment.

[0024] Furthermore, the transmission device of the device is used to move the hot pressing assembly, and it integrates a distance sensor to precisely control the distance between the hot pressing assembly and the substrate on the working platform, ensuring the control accuracy at the micrometer level, thereby forming perovskite films of different thicknesses.

[0025] The beneficial effects of this invention are:

[0026] 1. Dense, uniform, and flat perovskite films can be prepared by confined hot pressing method;

[0027] 2. The process is simple and controllable, and the nucleation and crystallization process of large-area perovskite films can be precisely controlled, and the thickness of the perovskite film can be precisely adjusted.

[0028] 3. This equipment can automatically select the corresponding working area according to the size of the substrate, avoiding waste of perovskite precursor solution. In addition, this equipment innovatively integrates coating structure and annealing equipment, effectively reducing costs.

[0029] This invention proposes an apparatus and method for preparing large-area perovskite thin films using confined hot pressing. Firstly, the confined hot pressing apparatus, due to its microstructure, allows for precise and uniform deposition of droplets onto the substrate, facilitating the formation of a uniform, dense, and flat perovskite wet film, thus enabling the production of large-area, continuous, pinhole-free perovskite thin films. Secondly, by adjusting the distance between the hot pressing components and the substrate on the working platform, the apparatus can precisely control the nucleation and crystallization processes of the large-area perovskite thin film and precisely adjust its thickness. Furthermore, the apparatus can autonomously select the corresponding working area based on the substrate size, avoiding waste of the perovskite precursor solution. The innovative integration of the coating structure with the annealing equipment further reduces costs. Finally, this apparatus and method for preparing large-area perovskite thin films using confined hot pressing offers advantages such as simple process, easy operation, low cost, and low requirements for precision and airtightness, contributing to the industrial production and application of large-area perovskite solar cells.

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of an apparatus for preparing large-area perovskite thin films by confined hot pressing, provided in an embodiment of the present invention.

[0032] Figure 2 A detailed view of the bottom channel of the hot pressing assembly of an apparatus for preparing large-area perovskite thin films by confined hot pressing, provided in an embodiment of the present invention;

[0033] Figure 3 This is a detailed diagram of the top perovskite precursor solution injection structure of a confined hot pressing device for preparing large-area perovskite thin films, provided in an embodiment of the present invention. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0035] Example 1

[0036] This invention provides a method for preparing large-area perovskite thin films by confined hot pressing, comprising the following steps:

[0037] Step 1: Prepare the perovskite precursor solution;

[0038] Step 2: Operate the transmission device 30 to control the hot pressing assembly 50 to maintain a certain distance from the substrate 20 on the working base 10;

[0039] Step 3: Inject the perovskite precursor solution into the top of the hot-pressing assembly 50, and use a booster to push the perovskite precursor solution into each channel.

[0040] Step 4: Once the perovskite precursor solution flows out from the bottom channels 40 of the hot-pressing assembly 50 and connects to form a dense, uniform, and flat perovskite wet film covering the substrate, stop the injection.

[0041] Step 5: Finely adjust the transmission device 30 according to the required perovskite film thickness to control the distance between the hot pressing assembly 50 and the substrate 20;

[0042] Step 6: Turn on the global heating system of the hot pressing assembly to dry the perovskite wet film and form a perovskite thin film, and slowly raise the hot pressing assembly 50 to allow the solvent in the perovskite precursor solution to evaporate.

[0043] Step 7: Turn on the heating device of the working platform 10 to anneal the perovskite film.

[0044] The perovskite precursor solution components include MAPbI3, MAPbBr3, MAPbCl3, and MAPbI 3-x Br x MAPbI 3-x Cl x MA y FA 1-y PbI3, MA y FA 1-y PbI 3-x Cl x MA y FA 1-y PbI 3-x Br x The solvent is any one of CsSnxPb1-xI3, CsPbI3, CsSnI3 and CsPbBr3, and is one or a mixture of dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), γ-butyrolactone (GBA), N-methyl-2-pyrrolidone (NMP), hydroiodic acid and dimethyl ethanol (2-ME).

[0045] The concentration of the prepared perovskite precursor solution was 1-2.5 mol / mL.

[0046] Based on the above methods for growing large-area perovskite thin films, this invention also provides an apparatus for preparing large-area perovskite thin films by confined hot pressing, as described above. Figure 1 , Figure 2 ,and Figure 3 ,include:

[0047] The working platform 10 is used to place the substrate 20. It integrates a vacuum adsorption device to ensure that the substrate 20 is fixed and does not move, and can perform annealing treatment on the perovskite film.

[0048] The hot-pressing assembly 50 is used to hot-press a perovskite thin film onto the surface of the substrate 20. Its top 60 is a perovskite solution injection structure; the bottom consists of high-density microchannels with a microstructure that allows the perovskite solution injected from the top to flow out continuously, forming a dense, uniform, and flat perovskite wet film. Each channel 40 at the bottom has an independent opening and closing function, allowing for the opening and closing of some channels depending on the substrate size, preventing perovskite solution from flowing out and contaminating the working platform 10. Furthermore, it has an internal global heating system that can quickly dry the perovskite precursor solution to form a perovskite thin film.

[0049] The transmission device 30 integrates a distance sensor, which can precisely control the distance between the hot pressing component 50 and the substrate 20 on the working platform 10, ensuring the control accuracy at the micrometer level, thereby forming perovskite films of different thicknesses.

[0050] Furthermore, the transmission device 30 is operated to control the hot pressing assembly 50 to maintain a distance of 500 μm from the substrate 20 on the working base 10.

[0051] Furthermore, a perovskite precursor solution is added through the top 60 of the hot-pressing assembly. The amount of solution added depends on the size of the substrate. The perovskite solution is pushed into each channel using the booster 70. The bottom of the hot-pressing assembly is observed. When the perovskite solution flowing out of the channel 40 forms a dense, uniform, and flat perovskite wet film on the substrate 20, the injection is stopped.

[0052] Furthermore, the transmission device 30 is finely adjusted to control the distance between the hot pressing component 50 and the substrate 20 to be between 30-300 μm, according to the required perovskite film thickness.

[0053] Furthermore, the global heating system for the hot-pressing component has a heating temperature between 150-250℃ and a duration of 1-2 minutes; the hot-pressing component speed is increased to 5-20 mm / s.

[0054] Furthermore, the working platform is heated and annealed at a temperature between 100-150℃ for 10-15 minutes.

[0055] Furthermore, the substrate 20 is made of any one of ITO conductive glass, ITO conductive plastic, FTO conductive glass, AZO conductive glass, ZTO conductive glass, ATO conductive glass, or Si wafer. The surface of the substrate 20 is covered with a dense oxide layer, which is any one of titanium dioxide (TiO2), tin dioxide (SnO2), zinc oxide (ZnO), or nickel oxide (NiO).

[0056] In this embodiment, the working platform 10 is used to place the substrate 20. It integrates a vacuum adsorption device to ensure the substrate 20 is fixed and does not move. The platform has a surrounding enclosure and a bottom heating function for annealing the perovskite film. The surrounding enclosure also prevents the perovskite precursor solution from flowing out of the platform and contaminating the environment. The hot-pressing assembly 50 has a cylindrical structure at its top 60 for injecting the perovskite precursor solution. The bottom consists of high-density small channels 40, all connected to the top injection structure. Due to its microstructure, the bottom channels allow the perovskite precursor solution to spread and connect, forming a dense, uniform, and flat perovskite wet film. Furthermore, the hot-pressing assembly has a global heating system that provides global heating during operation, enabling rapid drying of the perovskite wet film to form a perovskite film. The transmission device 30 is used to move the hot-pressing assembly. It integrates a distance sensor to precisely control the distance between the hot-pressing assembly and the substrate on the working platform, thereby forming perovskite films of different thicknesses. This equipment has a simple structure and is easy to operate. It has low requirements for precision and airtightness and can produce high-quality large-area perovskite thin films, which will help promote the industrial production and application of large-area perovskite solar cells.

[0057] Example 2

[0058] A perovskite thin film was prepared using the equipment for preparing large-area perovskite thin films by confined hot pressing as described in Example 1. The perovskite thin film in this example is a MAPbI3 thin film, and the preparation includes the following steps:

[0059] (1) Preparation of perovskite precursor solution

[0060] Specifically, weigh 238.5g MAI and 691.5g PbI2, add them to a 4ml wash-free bottle, place a magnetic stir bar inside, and add 1ml of dimethyl ethanol (2-ME). Place the bottle on a stirrer and wait for the solvent to dissolve completely to obtain a MAPbI3 solution (concentration 1.5mol / ml).

[0061] (2) Operate the transmission device 30 to control the hot pressing assembly 50 to maintain a distance of 500 micrometers from the substrate 20 on the working platform 10. The perovskite film prepared in this example has an area of ​​5cm*5cm. Therefore, it is necessary to control the hot pressing assembly 50 to open the bottom 5.5cm*5.5cm channel and close the other channels.

[0062] (3) Inject the perovskite precursor solution into the top 60 solution injection structure of the hot-pressing assembly, and use the booster 70 to push the perovskite precursor solution into each channel.

[0063] (4) The perovskite precursor solution flows out from each of the holes 40 at the bottom of the hot pressing assembly and connects to form a dense, uniform, and flat perovskite wet film that covers the substrate 20.

[0064] (5) According to the required perovskite film thickness, the transmission device 30 is finely adjusted to control the distance between the hot pressing component 50 and the substrate 20 to be 200μm;

[0065] (6) Turn on the global heating system of the hot pressing assembly at 150°C for 1 minute to quickly dry the perovskite wet film and form a perovskite thin film. Slowly lift the hot pressing mechanism at a rate of 5 mm / s to allow the solvent in the perovskite precursor solution to evaporate.

[0066] (7) Turn on the heating device of the working base 10, set the temperature to 100℃ and the duration to 10min, and anneal the perovskite film.

[0067] In this example, the substrate 20 is made of ITO conductive glass, but it is not limited to this; it can also be any of ITO conductive plastic, FTO conductive glass, AZO conductive glass, ZTO conductive glass, ATO conductive glass, Si wafer, etc. In this embodiment, the surface of the substrate 20 is covered with a dense SnO2 layer, but it is not limited to this. The oxide layer is any of titanium dioxide (TiO2), tin dioxide (SnO2), zinc oxide (ZnO), and nickel oxide (NiO).

[0068] Example 3

[0069] A perovskite thin film was prepared using the equipment for preparing large-area perovskite thin films by confined hot pressing as described in Example 1. The perovskite thin film in this example is MA. 0.6 FA 0.4 PbI3 thin film, including the following steps:

[0070] (1) Preparation of perovskite precursor solution

[0071] Specifically, weigh 119.25g MAI, 85.985g FAI, and 576.25g PbI2, add them to a 4ml sterile bottle, and place a magnetic stir bar inside. Measure 1ml of dimethyl ethanol (2-ME) and add it to the bottle. Place the bottle on a stirrer and wait for complete solvent removal to obtain MA. 0.6 FA 0.4 PbI3 solution (concentration 1.25 mol / ml);

[0072] (2) Operate the transmission device 30 to control the hot pressing assembly 50 to maintain a distance of about 500 μm from the substrate 20 on the working platform 10. The perovskite film prepared in this example has an area of ​​10 cm * 10 cm. Therefore, it is necessary to control the hot pressing assembly 50 to open the bottom 10.5 cm * 10.5 cm channel and close the other channels.

[0073] (3) Inject the perovskite precursor solution into the solution injection structure 60 at the top of the hot pressing assembly, and use the booster 70 to push the perovskite precursor solution into each channel.

[0074] (4) The perovskite precursor solution flows out from each of the channels 40 at the bottom of the hot pressing assembly and connects to form a dense, uniform, and flat perovskite wet film covering the substrate 20.

[0075] (5) According to the required perovskite film thickness, finely adjust the transmission device 30 to control the distance between the hot pressing component 50 and the substrate 20 to be 250μm;

[0076] (6) Turn on the global heating system of the hot pressing component to 200°C for 1 minute to quickly dry the perovskite wet film and form a perovskite thin film. Slowly raise the hot pressing component to 50°C at a rate of 8 mm / s to allow the solvent in the perovskite precursor solution to evaporate.

[0077] (7) Turn on the heating device of the working base 10, set the temperature to 120℃ and the duration to 12min, and anneal the perovskite film.

[0078] In this example, the substrate 20 is made of ITO conductive plastic, but it is not limited to this; it can also be any of ITO conductive glass, FTO conductive glass, AZO conductive glass, ZTO conductive glass, ATO conductive glass, Si wafer, etc. In this embodiment, a dense NiO layer is covered on the surface of the substrate 20, but it is not limited to this. The oxide layer is any of titanium dioxide (TiO2), tin dioxide (SnO2), zinc oxide (ZnO), and nickel oxide (NiO).

[0079] Example 4

[0080] A perovskite thin film was prepared using the equipment for preparing large-area perovskite thin films by confined hot pressing as described in Example 1. The perovskite thin film in this example is an FAPbI3 thin film, and the process includes the following steps:

[0081] (1) Preparation of perovskite precursor solution

[0082] Specifically, weigh 171.97g FAI and 461g PbI2, add them to a 4ml wash-free bottle, and place a magnetic stir bar inside. Measure 0.9ml of dimethyl ethanol (2-ME) and 0.1ml of N-methyl-2-pyrrolidone (NMP) and add them together. Place the bottle on a stirrer and wait until the solvent is completely dissolved to obtain a FAPbI3 solution (concentration 1mol / ml).

[0083] (2) Operate the transmission device 30 to control the hot pressing assembly 50 to maintain a distance of about 500 μm from the substrate 20 on the working platform 10. The perovskite film area prepared in this example is 15 cm * 15 cm. Therefore, it is necessary to control the hot pressing assembly 50 to open the bottom 15.5 cm * 15.5 cm channel and close the other channels.

[0084] (3) Inject the perovskite precursor solution into the top 60 solution injection structure of the hot-pressing assembly, and use the booster 70 to push the perovskite precursor solution into each channel.

[0085] (4) The perovskite precursor solution flows out from each of the holes 40 at the bottom of the hot pressing assembly and connects to form a dense, uniform, and flat perovskite wet film that covers the substrate 20.

[0086] (5) According to the required perovskite film thickness, the transmission device 30 is finely adjusted to control the distance between the hot pressing component 50 and the substrate 20 to be 300μm;

[0087] (6) Turn on the global heating system of the hot pressing assembly at 250°C for 1 minute to quickly dry the perovskite wet film and form a perovskite thin film. Slowly lift the hot pressing mechanism at a rate of 10 mm / s to allow the solvent in the perovskite precursor solution to evaporate.

[0088] (7) Turn on the heating device of the working base 10, set the temperature to 150℃ and the duration to 15min, and anneal the perovskite film.

[0089] In this example, substrate 20 is made of FTO conductive glass, but it is not limited to this; it can also be made of ITO conductive plastic, AZO conductive glass, ZTO conductive glass, ATO conductive glass, Si wafer, etc. In this embodiment, a dense TiO2 layer is coated on the surface of substrate 20, but it is not limited to this. The oxide layer is any one of titanium dioxide (TiO2), tin dioxide (SnO2), zinc oxide (ZnO), and nickel oxide (NiO).

[0090] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0091] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0092] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0093] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0094] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0095] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for preparing large-area perovskite thin films by confined hot pressing, characterized in that: Includes the following steps: Step 1: Prepare the perovskite precursor solution; Step 2: Operate the transmission device to control the hot pressing assembly to maintain a certain distance from the substrate on the working platform; wherein, the bottom of the hot pressing assembly includes: high-density small channels, which allow the perovskite precursor solution to flow out and connect to form a dense, uniform, and flat perovskite wet film; the transmission device integrates a distance sensor, which can accurately control the distance between the hot pressing assembly and the substrate on the working platform at the micrometer level. Step 3: Inject the perovskite precursor solution into the top of the hot-pressing assembly and use a booster to push the perovskite precursor solution into each channel. Step 4: Once the perovskite precursor solution flows out from the bottom channels of the hot-pressing assembly and connects to form a dense, uniform, and flat perovskite wet film that covers the substrate, stop the injection process. Step 5: Finely adjust the transmission device according to the required perovskite film thickness to control the distance between the hot pressing assembly and the substrate; Step 6: Turn on the global heating system of the hot pressing assembly to dry the perovskite wet film and form a perovskite thin film, and slowly raise the hot pressing mechanism to allow the solvent in the perovskite precursor solution to evaporate. Step 7: Turn on the heating device of the work platform to anneal the formed perovskite film.

2. The method for preparing large-area perovskite thin films according to claim 1, characterized in that: The perovskite precursor solution composition includes MAPbI3, MAPbBr3, MAPbCl3, and MAPbI 3-x Br x MAPbI 3-x Cl x MA y FA 1-y PbI3, MA y FA 1- y PbI 3-x Cl x MA y FA 1-y PbI 3-x Br x Any one of CsSnxPb1-xI3, CsPbI3, CsSnI3, and CsPbBr3.

3. The method for preparing large-area perovskite thin films according to claim 1, characterized in that: The concentration of the prepared perovskite precursor solution is 1-2.5 mol / mL.

4. An apparatus for preparing large-area perovskite thin films by confined hot pressing, applied to the method described in any one of claims 1-3, characterized in that: include: The working platform is used to place the substrate. It integrates a vacuum adsorption device to ensure that the substrate is fixed and does not move, and can perform annealing treatment on the perovskite film. A hot pressing assembly is used to hot press a perovskite film onto a substrate surface; wherein, the equipment structure consists of a hot pressing assembly on top and a working platform below, which are parallel to each other and the distance between them is controlled by a rear transmission device. A transmission device is used to move the hot pressing assembly and control the distance between the hot pressing assembly and the substrate on the working platform, thereby forming perovskite films of different thicknesses. The transmission device of the device is used to move the hot pressing assembly, and its internal distance sensor can accurately control the distance between the hot pressing assembly and the substrate on the working platform, with the control accuracy guaranteed at the micrometer level, thereby forming perovskite films of different thicknesses.

5. The apparatus for preparing large-area perovskite thin films according to claim 4, characterized in that: The hot pressing assembly of the device includes a perovskite precursor solution injection structure and integrates a global heating system.

6. The apparatus for preparing large-area perovskite thin films according to claim 5, characterized in that: The hot pressing component of the device has a bottom composed of high-density small channels with a microstructure, which allows the perovskite precursor solution injected from the top to flow out and connect, forming a dense, uniform, and flat perovskite wet film.

7. The apparatus for preparing large-area perovskite thin films according to claim 6, characterized in that: The hot pressing assembly of the device has independent opening and closing functions for each channel at the bottom. Depending on the size of the substrate, some channels can be opened or closed to prevent the perovskite precursor solution from flowing out and contaminating the working platform.

8. The apparatus for preparing large-area perovskite thin films according to claim 4, characterized in that: The working platform of the device is used to place the substrate. It integrates a vacuum adsorption device to ensure that the substrate is fixed and does not move. The working platform has a surrounding fence structure and a heating function at the bottom, which can perform annealing treatment on the perovskite film. The surrounding fence structure can also ensure that the perovskite precursor solution does not flow out of the platform and pollute the environment.

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