Apparatus and method for preparing perovskite thin film and perovskite solar cell module

Abstract

The application provides a device and method for preparing a perovskite thin film and a perovskite solar cell component, and relates to the technical field of perovskite solar cells. The application adds a heating component to the sample cabin on the basis of the air pumping and ventilation method, compensates for the problem that the solvent is difficult to effectively and quickly evaporate due to the temperature reduction in the sample cabin in the vacuum pumping instant, makes the perovskite liquid film reduce the gas pressure of the residual solvent under the action of multiple factors such as air pumping, ventilation and heating, makes the solvent quickly evaporate and be pumped away, reduces the solvent residue, thereby reduces the holes at the buried interface, and improves the uniformity and photoelectric performance of the thin film. The device and method can be used to prepare a large-area, high-quality perovskite thin film which is uniform, dense and pore-free. The perovskite solar cell component composed of the perovskite thin film is efficient and stable, the component quasi-steady-state efficiency is as high as 22.4% (the aperture area is 26.02cm 2 ), and the current certified efficiency world record value is obtained.

Description

Technical Field

[0001] This invention relates to the field of perovskite solar cell technology, and more particularly to an apparatus and method for preparing large-area perovskite thin films and a perovskite solar cell module. Background Technology

[0002] Over the past decade, the photoelectric conversion efficiency of laboratory-scale perovskite organometal halide solar cells (hereinafter referred to as perovskite solar cells) has rapidly increased from an initial 3.8% to 26.0%, sparking a research boom both domestically and internationally. Perovskite materials, as novel light-absorbing materials, possess the following characteristics: 1) low exciton binding energy; 2) fast carrier diffusion rate and long diffusion distance; 3) broad absorption spectrum; 4) tunable ionic composition and band gap; and 5) solution-processable preparation. These characteristics give perovskite materials greater competitiveness and demonstrate enormous application potential.

[0003] However, laboratory-sized perovskite solar cells (<0.1 cm⁻¹) 2 ) and perovskite components (>20cm) 2 There remains a significant gap in efficiency, primarily due to the controllable preparation of large-area perovskite thin films. Currently, commonly used methods for preparing large-area perovskite thin films include one-step methods, blade coating, and slot coating. While the one-step method is relatively simple to operate, it still faces numerous challenges in large-area perovskite film preparation: the uniformity and crystallinity of the film cannot be effectively controlled, and films prepared by blade coating and slot coating exhibit defects such as coarse grains, low substrate coverage, cracks, and pores, leading to severe leakage current and non-radiative recombination in the cells, which is detrimental to the commercial operation of perovskite solar cells. Therefore, obtaining high-quality perovskite thin films that are uniform, dense, well-bonded, and free of pores and cracks is crucial for developing efficient and stable perovskite modules. Summary of the Invention

[0004] In view of this, the object of the present invention is to provide an apparatus and method for preparing perovskite thin films and a perovskite solar cell module. The apparatus and method of the present invention enable the preparation of large-area, high-quality perovskite thin films.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides an apparatus for preparing perovskite thin films, including a sample chamber, which is a sealed chamber formed by a conical cavity 1, a sealing gasket 7, and a base 5; the sealing gasket 7 has a hollow structure and is symmetrically arranged with several through holes 8 communicating with the atmosphere; the conical cavity 1 is placed on the surface of the sealing gasket 7, covering the hollow structure; the base 5 is located below the sealing gasket 7.

[0007] A buffer tank 2 is connected to the conical cavity 1 via a first pipe, and a first valve 4-1 is provided on the first pipe;

[0008] A vacuum pump 3 is connected to the buffer tank 2 via a second pipe, and a second valve 4-2 is provided on the second pipe;

[0009] and a heating element for heating the sample chamber.

[0010] Preferably, the sealing gasket 7 is a silicone gasket; the diameter of the through hole 8 is less than 3 mm, and the number of through holes 8 is 4 to 128.

[0011] Preferably, the heating element is a heating platform located below the base 5 or an infrared coil located inside the conical cavity 1.

[0012] Preferably, a first pressure gauge 6-1 is provided on the first pipe between the conical cavity 1 and the first valve 4-1; a second pressure gauge 6-2 is provided on the buffer tank 2.

[0013] This invention provides a method for preparing perovskite thin films using the apparatus described above, comprising the following steps:

[0014] The pressure inside the buffer tank 2 is pre-evacuated to 0.1–500 Pa using vacuum pump 3;

[0015] The heating element is turned on to preheat the sample chamber. The perovskite liquid film is placed in the hollow part of the sealing gasket 7 in the sample chamber, and the liquid level of the perovskite liquid film is level with the center of the through hole 8. Then, the first valve 4-1 is opened to create a vacuum in the sample chamber, while the outside atmosphere is vented into the sample chamber through the through hole 8. The vacuum pump 3 is kept on at all times. Under the synchronous action of evacuation, heating and ventilation, the solvent in the perovskite liquid film is removed to obtain a perovskite thin film.

[0016] Preferably, the heating element is set to a heating temperature of 60–150°C.

[0017] Preferably, the synchronous action time of the air extraction, heating and ventilation is 10s to 10min.

[0018] The present invention provides perovskite thin films prepared by the methods described in the above technical solutions.

[0019] Preferably, the thickness of the perovskite thin film is 100–2000 nm, and the area is 2–20000 cm². 2 .

[0020] The present invention also provides a perovskite solar cell module, comprising a substrate, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and an electrode layer, wherein the perovskite light-absorbing layer is the perovskite thin film described in the above technical solutions.

[0021] This invention provides an apparatus for preparing perovskite thin films, comprising a sample chamber, which is a sealed chamber formed by a conical cavity 1, a sealing gasket 7, and a base 5; the sealing gasket 7 is a hollow structure with a plurality of through holes 8 symmetrically arranged around it, communicating with the atmosphere; the conical cavity 1 is placed on the surface of the sealing gasket 7, covering the hollow structure; the base 5 is located below the sealing gasket 7; a buffer tank 2 connected to the conical cavity 1 through a first pipe, the first pipe being provided with a first valve 4-1; a vacuum pump 3 connected to the buffer tank 2 through a second pipe, the second pipe being provided with a second valve 4-2; and a heating component for heating the sample chamber. Simple evacuation and ventilation methods rapidly reduce the temperature inside the sample chamber during the evacuation process, slowing down the solvent vaporization rate and leaving some solvent residue in the perovskite film. During subsequent heating and annealing, solvent evaporation can lead to defects such as pores and cracks in the film. This invention adds a heating component to the sample chamber based on the evacuation and ventilation method. Heating compensates for the problem of solvent residue caused by the temperature drop inside the sample chamber during vacuuming, which makes it difficult to evaporate effectively and quickly. Under the combined effects of evacuation, ventilation, and heating, the gas pressure of the residual solvent in the perovskite liquid film is reduced, allowing it to evaporate and be removed quickly, reducing solvent residue. This reduces pores at the buried interface of the film and improves the uniformity and photoelectric properties of the film.

[0022] This invention provides a method for preparing perovskite thin films. Specifically, it is a method based on heating-assisted vacuum evacuation and ventilation. In this method, a liquid perovskite film is placed in a sample chamber with perforations. A buffer tank is evacuated to achieve an extremely low vacuum. The sample chamber is opened and closed using a valve, allowing for rapid solvent extraction. Under heating by a heating element and by introducing a non-reactive gas through the perforations, the concentration of solvent molecules is diluted, achieving ultra-rapid solvent extraction from the liquid perovskite film (the solvent can be removed in approximately 1 / 1000 of a second). This promotes heterogeneous nucleation and growth of perovskite on the substrate surface, resulting in a uniform, dense, pore-free, and crack-free large-area, high-quality perovskite thin film. Furthermore, the method provided by this invention has many advantages, including simple operation, easy scalability, low cost, high repeatability, and ease of industrialization.

[0023] This invention provides a perovskite thin film prepared by the method described above. The perovskite thin film provided by this invention is a large-area, high-quality perovskite thin film. Perovskite solar cell modules constructed from this perovskite thin film are highly efficient and stable. Certified by the authoritative Fuzhou Institute of Metrology, the module's quasi-steady-state efficiency reaches as high as 22.4% (pore area 26.02 cm²). 2(Note: This aperture area refers to the area of ​​the square hole on the opaque metal mask used to test perovskite solar cell modules.) This is the highest efficiency value for perovskite modules at this size, and this record is included in the 62nd edition of Solar Cell Efficiency Tables. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the apparatus for preparing perovskite thin films provided by the present invention. Figure 1 1-Conical cavity, 2-Buffer tank, 3-Vacuum pump, 4-1-First valve, 4-2-Second valve, 4-3-Third valve, 5-Base, 6-1-First pressure gauge, 6-2-Second pressure gauge, 7-Sealing gasket, 8-Through hole;

[0025] Figure 2 This is a physical diagram of a portion of the device consisting of a base and a sealing gasket, as described in an embodiment of the present invention.

[0026] Figure 3 These are physical images of the large-area (6.5cm × 7cm) perovskite thin films from Example 1 and Comparative Examples 1-2. Figure 3 From left to right, the images show the perovskite films prepared in Comparative Example 1 (antisolvent method), Comparative Example 2 (vacuuming and ventilation method), and Example 1 (heating and vacuuming and ventilation method).

[0027] Figure 4 The image shown is a scanning electron microscope (SEM) image of a large-area perovskite thin film obtained using the conventional anti-solvent method in Comparative Example 1. Figure 4 A is the top surface morphology of the perovskite film, B is the bottom surface morphology of the perovskite film, and C is a cross-sectional view of the perovskite film.

[0028] Figure 5 The image shown is a scanning electron microscope (SEM) image of a large-area perovskite thin film obtained by the vacuum-ventilation method in Comparative Example 2. Figure 5 A is the top surface morphology of the perovskite film, B is the bottom surface morphology of the perovskite film, and C is a cross-sectional view of the perovskite film.

[0029] Figure 6 This is a scanning electron microscope (SEM) image of a large-area perovskite thin film obtained by the heating-evacuation-ventilation method in Example 1. Figure 6 A is the top surface morphology of the perovskite film, B is the bottom surface morphology of the perovskite film, and C is a cross-sectional view of the perovskite film.

[0030] Figure 7 The solvent residue of perovskite films obtained by three different methods in Examples 1 and Comparative Examples 1-2 at different annealing times is shown. Figure 7In Figure A, the 1H NMR spectra of perovskite thin films obtained by the conventional antisolvent method (ASM) at different heating times in Comparative Example 1 are shown. 1 H NMR spectra, B is the comparative example 2 perovskite thin film obtained by vacuum-permeable (GPM) method with different heating times. 1 H NMR spectra, C represents the perovskite thin films obtained in Example 1 using the heating-pump-gas-purging (TGPM) method with different heating times. 1 H NMR spectra, D is the curve of the relative content of residual DMSO in perovskite films obtained by three different methods as a function of heat treatment time;

[0031] Figure 8 The steady-state and transient fluorescence decay curves of perovskite films prepared by three different methods are shown in Example 1 and Comparative Examples 1-2. Figure 8 In the image, A is the steady-state fluorescence curve, and B is the time-resolved fluorescence decay curve.

[0032] Figure 9 The images show the actual perovskite component in Example 1, along with the lines P1, P2, and P3 etched using laser etching technology and their corresponding widths. Figure 9 Image A shows the actual perovskite component, while image B shows the P1, P2, and P3 etching lines and their corresponding widths created using laser etching technology.

[0033] Figure 10 The photoelectric performance statistics of perovskite components assembled from perovskite thin films prepared by three different methods in Examples 2 and Comparative Examples 3-4 are shown.

[0034] Figure 11 The efficiency of the perovskite solar cell module in Example 2, as certified by a third-party authority, was recorded. Figure 11 In Figure A, the certified IV curve and related photoelectric performance parameters are shown; in Figure B, the certified steady-state curve and corresponding photoelectric performance parameters are shown.

[0035] Figure 12 The 1cm value included in the "Solar Cell Efficiency Tables (Version 62)" in the examples is... 2 Screenshot of records for perovskite solar cells and perovskite solar modules;

[0036] Figure 13 This is a graph showing the stability test results of the perovskite module in Example 2. Figure 13 Figure A shows the results of the room temperature light stability test, and Figure B shows the results of the damp heat stability test.

[0037] Figure 14 Examples 3 and Comparative Examples 5-6 are based on three different preparation methods at a depth of 1 cm. 2 IV curves of perovskite solar cells of various sizes;

[0038] Figure 15 Example 3, 1cm, certified by a third-party authority. 2 New record efficiency for perovskite solar cells. Figure 15 Figure A shows the certified IV curve and related photoelectric performance parameters, while Figure B shows the certified steady-state curve and corresponding photoelectric performance parameters. Detailed Implementation

[0039] This invention provides an apparatus for preparing perovskite thin films, including a sample chamber, which is a sealed chamber formed by a conical cavity 1, a sealing gasket 7, and a base 5; the sealing gasket 7 has a hollow structure and is symmetrically arranged with several through holes 8 communicating with the atmosphere; the conical cavity 1 is placed on the surface of the sealing gasket 7, covering the hollow structure; the base 5 is located below the sealing gasket 7.

[0040] A buffer tank 2 is connected to the conical cavity 1 via a first pipe, and a first valve 4-1 is provided on the first pipe;

[0041] A vacuum pump 3 is connected to the buffer tank 2 via a second pipe, and a second valve 4-2 is provided on the second pipe;

[0042] and a heating element for heating the sample chamber.

[0043] Figure 1 This is a schematic diagram of the apparatus for preparing perovskite thin films provided by the present invention, which is described below in conjunction with... Figure 1 Please provide a detailed explanation.

[0044] The device provided by the present invention includes a sample chamber, which is a sealed chamber formed by a conical cavity 1, a sealing gasket 7, and a base 5.

[0045] In this invention, the sealing gasket 7 has a hollow structure and is symmetrically arranged with several through holes 8 communicating with the atmosphere. These through holes can be specifically implemented by pre-embedding needles. This invention does not have particular requirements on the shape of the inner and outer contours of the sealing gasket; it can be circular or square. In this embodiment, both the inner and outer contours of the sealing gasket 7 are preferably circular, specifically preferably an annular silicone gasket. In this invention, the diameter of the through holes 8 is preferably less than 3 mm, and the number of through holes 8 is preferably 4 to 128. In this invention, the through holes are used to connect the inside and outside of the sample chamber, achieving the effect of air intake and ventilation. The arrangement of the through holes in this invention is beneficial for forming a uniform flow field within the sample chamber. In this invention, the hollow portion of the sealing gasket 7 is used to place the sample for preparing the perovskite thin film. The size of the hollow portion is determined according to the size of the sample being prepared, and is generally set to a diameter of 5 to 100 cm. Since the perovskite thin film prepared in this embodiment is square in size, a silicone plate with a square groove is also provided in the sealing gasket 7 in this embodiment. The square groove is used to fix the FTO or ITO substrate coated with the perovskite liquid film.

[0046] In this invention, the conical cavity 1 is fitted onto the surface of the sealing gasket 7, covering the hollow structure; the material of the conical cavity 1 is preferably hard metal. In this invention, the base 5 is located below the sealing gasket 7, the size of the base 5 is preferably larger than the size of the sealing gasket 7, and the material of the base 5 is preferably hard metal.

[0047] The device provided by this invention includes a buffer tank 2 connected to a conical cavity 1 in the sample chamber via a first pipe. In this invention, the first pipe is preferably positioned above the conical cavity 1; a first valve 4-1 is provided on the first pipe, preferably a solenoid valve; a first pressure gauge 6-1 is preferably provided on the first pipe between the conical cavity 1 and the first valve 4-1. This invention does not have any special requirements for the buffer tank 2; any buffer tank well-known to those skilled in the art can be used. In this invention, a second pressure gauge 6-2 is preferably provided on the buffer tank 2, and a third valve 4-3 is also preferably provided on the buffer tank 2. This invention does not have any special requirements for the third valve 4-3; any connecting valve well-known to those skilled in the art can be used. The third valve 4-3 is used to release the equipment pressure and restore atmospheric pressure after operation. In this embodiment of the invention, the buffer tank 2 is preferably a metal tank, and the volume of the buffer tank 2 is preferably 100–3000 L, more preferably 300 L.

[0048] The device provided by this invention includes a vacuum pump 3 connected to the buffer tank 2 via a second pipe. In this invention, a second valve 4-2 is provided on the second pipe. This invention does not have any special requirements for the second valve 4-2; any connection valve well-known to those skilled in the art can be used. Similarly, this invention does not have any special requirements for the vacuum pump 3; any vacuum pump well-known to those skilled in the art can be used. In this embodiment, the vacuum pump is an Edwards mechanical pump (Edwards E2M28FX115 / 200-230V, 1-ph, 50 / 60Hz with IEC60320). This invention uses the opening and closing of the second valve to evacuate the buffer tank 2 via the vacuum pump, which in turn allows the sample chamber 1 to be rapidly evacuated by opening the first valve 4-1.

[0049] The device provided by this invention includes a heating component for heating the sample chamber 1. In this invention, the heating component is preferably a heating platform disposed below the base 5 or an infrared coil disposed inside the conical cavity 1. Simple evacuation and ventilation methods rapidly reduce the temperature inside the sample chamber during the evacuation process, decreasing the solvent vaporization rate and leaving some solvent residue in the perovskite film. During subsequent heating and annealing, solvent evaporation can lead to defects such as pores and cracks in the film. This invention, based on the evacuation and ventilation method, adds a heating component to the sample chamber. By adjusting the temperature, the gas pressure of the residual solvent in the perovskite liquid film is reduced under the combined effects of evacuation, ventilation, and heating, causing it to evaporate rapidly and be removed, reducing solvent residue and thus reducing porosity at the buried interface, improving the uniformity and photoelectric properties of the film.

[0050] This invention provides a method for preparing perovskite thin films using the apparatus described above, comprising the following steps:

[0051] The pressure inside the buffer tank 2 is pre-evacuated to 0.1–500 Pa using vacuum pump 3;

[0052] The heating element is turned on to preheat the sample chamber. The perovskite liquid film is placed in the hollow part of the sealing gasket 7 in the sample chamber, and the liquid level of the perovskite liquid film is level with the center of the through hole 8. Then, the first valve 4-1 is opened to create a vacuum in the sample chamber, while the outside atmosphere is vented into the sample chamber through the through hole 8. The vacuum pump 3 is kept on at all times. Under the combined action of vacuuming, heating and ventilation, the solvent in the perovskite liquid film is removed, and a perovskite thin film is obtained.

[0053] In this invention, the perovskite liquid film is preferably obtained by drop-coating a perovskite precursor solution onto a cleaned FTO or ITO substrate using spin coating, blade coating, or slot coating. This invention does not have special requirements regarding the composition of the perovskite precursor solution; any perovskite precursor solution well-known to those skilled in the art can be used. In an embodiment of this invention, the preferred method for preparing the perovskite precursor solution is as follows: methylamine iodide (MAI, 99.99%, Greatcell), formamidine iodide (FAI, 99.99%, Greatcell), cesium chloride (or cesium iodide, i.e., CsCl or CsI, 99.9%, Xi'an Baolai Te), methylamine chloride (MACl, 99.99%, Greatcell), and lead iodide (PbI2, 99.99%, TCI) are dissolved in an organic solvent in a certain proportion, and the mixture is stirred thoroughly to obtain the perovskite precursor solution. This invention does not have special requirements regarding the organic solvent; any solvent well-known to those skilled in the art can be used. Any organic solvent can be used, specifically one or more of formic acid (Fa), acetic acid (AC), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP), gamma-lactone (GBL), tetrahydrothiophene 1-oxide (THTO), isopropanol (IPA), and dimethyl ethanol (MEO); the molar amounts of CsCl, MAI, FAI, and MACl are preferably 0-10%, 0-50%, 50-90%, and 5-50% of the molar amount of PbI2, respectively, and more preferably 5-8%, 5-10%, 80-90%, and 30-40% of the molar amount of PbI2, respectively. The perovskite precursor solution formulated in this invention is beneficial for obtaining a stable perovskite film to the greatest extent. The general structural formula of perovskite is ABX3, mainly composed of MA x FA y Cs 1-x-y PbI3 is mainly composed of perovskite materials, among which CH3NH3 + (MA + CH(NH2)2 + (FA + ) and Cs + Represents the A-site cation, Pb 2+ Represents the B-site ion, I - Representing the X-position ion, these three ions constitute the structure of the perovskite crystal. Because FAPbI3-based perovskites exhibit phase instability, a certain amount of MACl is added during preparation. This component stabilizes the FAPbI3-based perovskite and gradually volatilizes during thermal annealing.

[0054] The present invention makes the liquid level of the perovskite liquid film level with the center of the through hole 8, so that the airflow can sweep across the surface of the perovskite liquid film during pumping and carry away the solvent.

[0055] In this invention, the heating temperature of the heating component is preferably 60–150°C, more preferably 90–100°C; the synchronous action time of the evacuation, heating, and ventilation is preferably 10 s–10 min. This invention provides a method for preparing perovskite thin films based on a heating-assisted vacuum evacuation and ventilation method (also known as a heating-evacuation-ventilation method). In this invention, the buffer tank 2 is first evacuated to a vacuum (0.1–500 Pa). The first valve 4-1 is then opened, and the cavity is rapidly evacuated, carrying away a large amount of solvent. Simultaneously, under the action of heating and ventilation, the vacuum pressure of the solvent is rapidly reduced, causing it to be largely removed. This process lasts for 10 s–10 min, after which the perovskite thin film is removed. Because the sample chamber has a through-hole, the pressure inside the cavity is rapidly evacuated the instant the valve is opened. Due to the pressure difference between the inside and outside, external gas automatically replenishes the cavity, while the externally connected vacuum pump continues to operate. Ultimately, the replenishment and evacuation reach a dynamic equilibrium. After dynamic equilibrium, the pressure inside the buffer tank is 20–2000 Pa.

[0056] After obtaining the perovskite film, the present invention preferably further includes annealing the perovskite film to obtain a crystalline perovskite film. In the present invention, the annealing preferably includes a first annealing and a second annealing performed sequentially, wherein the holding temperature of the first annealing is preferably 100°C and the holding time is preferably 1 hour, and the holding temperature of the second annealing is preferably 150°C and the holding time is preferably 10 minutes.

[0057] The principle of this invention for preparing perovskite thin films is as follows: During vacuum evacuation, the temperature inside the sample chamber drops instantly when the valve is activated, then rises again within a few seconds. This cooling process locks in some solvent evaporation, but the temperature returns to room temperature after a few seconds. Because the sample chamber is connected to an ultra-low pressure buffer tank, the pressure inside the sample chamber drops rapidly to about 1 Pa within a fraction of a second when the valve is opened. During this time, most of the solvent is removed. However, vacuum evacuation lowers the temperature inside the chamber, causing some solvent to remain inside the perovskite thin film and become difficult to remove. Simultaneously, under heterogeneous nucleation, the surface of the perovskite thin film preferentially nucleates to form a dense surface, sealing the pores on the lower surface. Therefore, based on these two reasons, simple vacuum evacuation and ventilation methods cannot effectively remove the solvent from the film. This invention utilizes a principle similar to freeze-drying, effectively avoiding the above phenomena through a combination of vacuum evacuation, ventilation, and simultaneous heating. Freeze-drying is a common method for drying food, pharmaceuticals, and other substances. Its principle involves freezing the substance at a low temperature and then heating it under reduced pressure, causing the water content to change from a solid to a gaseous state, thus achieving drying. The main steps of freeze-drying include: a) Freezing: Placing the substance to be dried in a low-temperature environment to freeze it into a solid state; b) Reducing pressure: Placing the frozen substance in a vacuum environment to lower the pressure; c) Heating: Heating the substance to raise its surface temperature, causing the ice crystals to convert into water vapor, thereby drying the substance. During freeze-drying, the water content inside the substance forms ice crystals due to the low temperature, while the external vacuum environment provides the conditions for the water to change from a solid to a gaseous state. Therefore, freeze-drying not only dries the substance but also preserves its original quality. This invention utilizes a principle similar to freeze-drying. Based on the vacuuming and ventilation method, the sample chamber is heated. This heating compensates for the problem of solvent residue caused by the temperature drop during vacuuming, which hinders effective and rapid evaporation. Under the combined effects of vacuuming, ventilation, and heating, the pressure of residual solvent in the perovskite liquid film is reduced, allowing it to evaporate and be removed rapidly. The method provided by this invention can quickly remove residual solvent from the perovskite liquid film, preventing pores at the perovskite buried interface, thereby reducing leakage current and non-radiative recombination in perovskite solar cells. It also facilitates the large-scale fabrication of large-area, high-quality perovskite thin films.

[0058] This invention achieves rapid solvent removal through completely synchronized vacuuming, heating, and venting. Existing technologies using vacuuming and venting methods to compensate for heat loss in perovskite liquid films or substrates involve preheating and drying the glass substrate and perovskite liquid film. This process involves heating first, followed by vacuuming and venting to remove the solvent, a difference in time scale compared to this invention. While preheating the glass substrate and perovskite liquid film at a low temperature can compensate for the temperature drop during vacuuming, it inevitably leads to heterogeneous nucleation and rapid growth of crystals at the perovskite-glass substrate interface, easily forming coarse perovskite dendrites and preventing the formation of a uniformly covered perovskite film. Furthermore, the formation of a dense perovskite film on the upper surface driven by heterogeneous nucleation at the gas-liquid interface also seals off the solvent on the lower surface, resulting in solvent residue. This invention, utilizing synchronized venting, vacuuming, and heating, effectively reduces solvent residue.

[0059] This invention provides a perovskite thin film prepared by the method described above. In this invention, the thickness of the perovskite thin film is preferably 100–2000 nm, more preferably 800 nm, and the area is preferably 2–20000 cm². 2 The perovskite thin film provided by this invention is a uniform, dense, and pore-free large-area, high-quality perovskite thin film.

[0060] The present invention also provides a perovskite solar cell module, comprising a substrate, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and an electrode layer. The perovskite light-absorbing layer is the perovskite thin film described in the above technical solutions, which is mainly used to absorb photons and generate electron-hole pairs. This invention does not impose special requirements on the substrate, electron transport layer, hole transport layer, and electrode layer; any materials well-known to those skilled in the art can be used. Specifically, the substrate is typically a transparent conductive oxide (TCO) thin film material, such as zinc oxide (ZnO) or tin oxide (SnO2), to provide a current transport path and light transmittance. The electron transport layer is typically TiO2, which receives electrons from the perovskite layer and transports them to the electrodes. The hole transport layer is typically an organic material, such as dipropyl 2,2',7,7'-tetra(diphenylamino)-9,9'-anthrabenzodicarboxylate (Spiro-OMeTAD), which receives holes from the perovskite layer and transports them to the electrodes. The electrode layer is typically a metallic material, such as aluminum (Al), silver (Ag), or gold (Au), which transports electrons and holes out of the cell and forms a current. This invention does not impose special requirements on the fabrication method of the perovskite solar cell module; any fabrication method well-known to those skilled in the art can be used.

[0061] The perovskite solar cell module constructed from the perovskite thin film provided by this invention is highly efficient and stable. Certified by the authoritative Fuzhou Institute of Metrology, the module's quasi-steady-state efficiency reaches as high as 22.4% (pore area 26.02 cm²). 2 This is the highest efficiency value for perovskite components at this size.

[0062] To further illustrate the present invention, the apparatus and method for preparing perovskite thin films and perovskite solar cell modules provided by the present invention are described in detail below with reference to examples, but these should not be construed as limiting the scope of protection of the present invention.

[0063] Example 1: Preparation of large-area perovskite thin films

[0064] Preparation of perovskite precursor solution: 645.4 mg of lead iodide (PbI2), 216.7 mg of formamidine iodide (FAI), 11.1 mg of methylamine iodide (MAI), 11.8 mg of cesium chloride (CsCl), and 33.1 mg of methylamine chloride (MACl) were added to a mixed solvent of 200 μL DMSO and 800 μL DMF. The mixture was stirred thoroughly for 1–2 hours to obtain the perovskite precursor solution for later use.

[0065] Subsequently, the prepared perovskite precursor solution was used to prepare a perovskite liquid film using spin coating, blade coating, or slot coating methods. Figure 1 The device shown (see actual image) Figure 2 The perovskite liquid film (with 16 through-holes and a diameter of 0.6 mm) was subjected to a heated vacuum-pumped (TGPM) method to remove residual solvent from the film. The specific procedure was as follows: The perovskite liquid film was placed in a sample chamber with through-holes, and the sample chamber was placed on a hot stage set to 90°C. The sample chamber was connected to a vacuum pump and a buffer tank, and the opening and closing of the sample chamber was controlled by a solenoid valve. The buffer tank was evacuated to a vacuum (0.1 Pa) beforehand. When the solenoid valve was opened, the sample chamber was rapidly evacuated, removing a large amount of solvent. Simultaneously, under the combined effects of heating and ventilation, the vacuum pressure of the solvent was rapidly reduced, causing it to be largely removed. This process lasted for 6 minutes, after which the perovskite film was removed. The resulting perovskite film was then annealed on the hot stage at 100°C for 1 hour, and then at 150°C for 10 minutes to obtain a crystalline perovskite film.

[0066] Comparative Example 1

[0067] Preparation of perovskite thin films via conventional anti-solvent method (ASM):

[0068] The perovskite precursor solution (same as in Example 1) was drop-coated onto a cleaned FTO or ITO substrate. The coating process involved two spin-coating steps: 1000 rpm for 10 seconds and 4000 rpm for 30 seconds. In the last 10 seconds before the spin-coating was completed, 100 μL to 5 mL of chlorobenzene or diethyl ether was dropped. The resulting perovskite film was then placed on a hot plate and annealed at 100 °C for 1 hour, followed by annealing at 150 °C for 10 minutes to obtain a crystalline perovskite film.

[0069] Comparative Example 2

[0070] By omitting the heating element (heating stage), perovskite thin films are prepared using the gas extraction and ventilation (GPM) method.

[0071] A perovskite precursor solution (same as in Example 1) was drop-coated onto a cleaned FTO or ITO substrate. A perovskite liquid film was obtained by spin coating, blade coating, or slot coating. This liquid film was placed in a porous sample chamber connected to a vacuum pump and a buffer tank, with the chamber's opening and closing controlled by a solenoid valve. The buffer tank was first evacuated to a vacuum (0.1 Pa). The solenoid valve was then opened, rapidly creating a vacuum in the sample chamber and removing a large amount of solvent. After 6 minutes, the solenoid valve was closed, the perovskite film was removed, and placed on a hot plate. It was annealed at 100°C for 1 hour, then at 150°C for 10 minutes, finally yielding a crystalline perovskite film.

[0072] The perovskite films in Example 1 and Comparative Examples 1-2 were tested as follows:

[0073] Test 1: Morphology of perovskite thin films

[0074] Figure 3 These are physical images of the large-area (6.5cm × 7cm) perovskite thin films from Example 1 and Comparative Examples 1-2. Figure 3 From left to right, the images show perovskite films prepared according to Comparative Example 1 (anti-solvent method), Comparative Example 2 (vacuum-and-gas method), and Example 1 (heating-vacuum-and-gas method). Figure 3 It can be seen that the surface of the large-area perovskite film prepared by the antisolvent method is rough and whitish, and there are a large number of micropores; the surface of the film prepared by the gas extraction and ventilation method is slightly whitish and has a small number of micropores; while the surface of the film prepared by the method of the present invention is smooth and dense, and has a glossy black color.

[0075] Figure 4 The image shown is a scanning electron microscope (SEM) image of a large-area (6.5 cm × 7 cm) perovskite thin film obtained by the conventional anti-solvent method in Comparative Example 1. Figure 4Image A shows the morphology of the upper surface of the perovskite film, image B shows the morphology of the lower surface of the perovskite film, and image C shows a cross-sectional view of the perovskite film. Conventional antisolvent methods can effectively extract the solvent from the upper surface of the perovskite film, allowing for rapid nucleation and growth to form a dense surface. However, this method often requires careful control of the amount and rate of antisolvent application. Too fast an application rate can easily lead to pinholes, while too slow a rate can result in cracks. Furthermore, antisolvents are only suitable for smaller perovskite films and are difficult to apply to large-area perovskite modules. Additionally, the formation of a dense perovskite film on the upper surface traps the solvent on the lower surface. During subsequent heating, the evaporation of this solvent corrodes the perovskite grains, creating numerous large pores and cracks. These negatively impact charge transport and collection, and also easily lead to charge recombination, resulting in battery leakage current and reduced open-circuit voltage.

[0076] Figure 5 This is a scanning electron microscope (SEM) image of a large-area (6.5 cm × 7 cm) perovskite thin film obtained by the vacuum-ventilation method in Comparative Example 2. Figure 5 Image A shows the morphology of the upper surface of the perovskite film, image B shows the morphology of the lower surface of the perovskite film, and image C shows a cross-sectional view of the perovskite film. The vacuum evacuation and ventilation method, compared to the conventional anti-solvent method, can effectively remove solvent. However, because the solvent on the upper surface is rapidly removed, the film surface rapidly crystallizes to form a dense film, resulting in the inability to remove solvent at the buried interface between the perovskite and the substrate. This leaves a large amount of solvent remaining inside the perovskite. Simultaneously, the rapid temperature drop inside the chamber causes this residual solvent to remain inside the perovskite. During subsequent annealing, this solvent is released through the grain gaps. During evaporation, the solvent further corrodes the perovskite film, resulting in a series of unevenly sized cracks on the lower surface of the perovskite and numerous pores at the buried interface. Simultaneously, pinholes also form on the upper surface due to solvent evaporation.

[0077] Figure 6 This is a scanning electron microscope (SEM) image of a large-area (6.5cm × 7cm) perovskite thin film obtained by the heating-evacuation-ventilation method in Example 1. Figure 6 Image A shows the morphology of the upper surface of the perovskite film, image B shows the morphology of the lower surface of the perovskite film, and image C shows a cross-sectional view of the perovskite film. This invention prepares perovskite films by accelerating the solvent vaporization process under heat, allowing the solvent to be rapidly removed from both the upper surface and the bulk phase of the perovskite film, thus reducing the amount of solvent remaining inside the perovskite and ultimately obtaining a dense, non-porous perovskite film.

[0078] Test 2: Solvent Residue Content in Perovskite Thin Films

[0079] Perovskite films subjected to different heat treatment stages (i.e., different annealing times) were repeatedly rinsed with deuterated water (D2O) to obtain a D2O solution containing FAI, MACl, and DMSO. The solution was analyzed using 1H NMR spectroscopy. 1 The concentration of DSMO relative to FA in D2O solution was determined by ¹H NMR, and the results are as follows: Figure 7 As shown.

[0080] Figure 7 The solvent residues in Example 1 and Comparative Examples 1-2 are obtained using three different methods for perovskite films at different annealing times. Figure 7 In Figure A, the 1H NMR spectra of perovskite thin films obtained by the conventional antisolvent method (ASM) at different heating times in Comparative Example 1 are shown. 1 H NMR spectra, B is the comparative example 2 perovskite thin film obtained by vacuum-permeable (GPM) method with different heating times. 1 H NMR spectra, C represents the perovskite thin films obtained in Example 1 using the heating-pump-gas-purging (TGPM) method with different heating times. 1 H NMR spectra, D is the curve of the relative content of residual DMSO in perovskite films obtained by three different methods as a function of heat treatment time.

[0081] Figure 7 The amount of solvent residue in perovskite films at different annealing times is quantitatively estimated by liquid nuclear magnetic resonance spectroscopy. It can be clearly seen that the conventional antisolvent method has a large amount of residual solvent, followed by the vacuum pumping and ventilation method. However, the method of Example 1 of this invention can effectively remove the residual solvent.

[0082] Test 3: Fluorescence and transient fluorescence of perovskite thin films

[0083] Defect states of perovskite thin films were determined using steady-state and transient fluorescence measurements. Steady-state measurements were obtained using an Acton SP-2558 laser confocal Raman spectrometer (Princeton Instruments), a digital CCD image sensor (PIXIS:100B_eXcelon), and a 485nm laser (PicoQuant LDH-PC-485). Transient fluorescence, an extension of steady-state spectroscopy, involved excitation with short laser pulses and detection of stimulated emission over time using a fast single-photon sensitive detector. This measurement was repeated multiple times to obtain statistical data on fluorescence emission. Transient fluorescence was measured using an Edinburgh Instruments TCSPC F900 fluorescence spectrometer. The test results are shown below. Figure 8 As shown.

[0084] Figure 8 The steady-state and transient fluorescence decay curves of perovskite films prepared by three different methods are shown in Example 1 and Comparative Examples 1-2. Figure 8Figure A shows the steady-state fluorescence curve, and Figure B shows the time-resolved fluorescence decay curve. Steady-state and transient fluorescence spectroscopy indicate the quality of perovskite films. Generally, the higher the intensity of steady-state fluorescence (PL), the higher the quality of the perovskite film and the more it can reduce non-radiative recombination within the film. Similarly, the slower the transient PL decays, the longer its lifetime, and the more effectively non-radiative recombination is suppressed. Figure 8 The optical properties of perovskite films prepared by the three methods can be reflected, and the perovskite film prepared by the present invention has the best quality.

[0085] Example 2: Fabrication of Perovskite Solar Cell Module

[0086] Preparation of spiro-OMeTAD solution for hole transport: Dissolve 105 mg of spiro-OMeTAD in 1343 μL of chlorobenzene, and add 41 μL of tetra-tert-butylpyridine, 25 μL of acetonitrile solution of Li-TFSI (517 mg of Li-TFSI dissolved in 1 mL of acetonitrile solvent), and 19 μL of acetonitrile solution of Co-TFSI (376 mg of Co-TFSI dissolved in 1 mL of acetonitrile solvent). Stir thoroughly for 1–2 hours to obtain spiro-OMeTAD solution.

[0087] Conductive glass pretreatment: Glass with dimensions of 6.5 × 7.0 cm... 2 The FTO substrate was etched using a laser etcher (Trotec, Austria) at 60% laser power, a speed of 300 mm / s, a frequency of 65 kHz, and a pulse width of 120 ns. The width of P1 was 41 μm. The laser-etched FTO substrate (Asahi FTO glass, 12–13 Ω / s²) was then sequentially cleaned in an ultrasonic bath with a cleaning agent (5% Hellmanex aqueous solution), deionized water, acetone, and isopropanol for 30 minutes each. The FTO substrate was then further cleaned with ultraviolet-ozone (UVO) surface treatment for 15 minutes.

[0088] Fabrication of perovskite solar cell modules:

[0089] Dense TiO2 layers (c-TiO2) and SnO2 layers (c-SnO2) were sequentially deposited on a clean FTO substrate using chemical bath deposition (CBD), following the preparation method described in J. Mater. Chem. A, 2018, 6, 10233-10242. The substrate was then annealed at 190°C for 60 minutes on a hot plate. After cooling, the substrate was treated with UVO for half an hour before use.

[0090] A 5 mg / mL isopropanol solution of phenylethylamine iodide (PEAI) was spin-coated onto the upper surface of the crystalline perovskite film prepared in Example 1 as a passivation layer, followed by spin-coating of a Spiro-OMeTAD hole transport layer. P2 was etched using an average laser power of 15%, a velocity of 1000 mm / s, a frequency of 65 kHz, and a pulse duration of 120 ns. The width of P2 was 92 μm. Finally, a 70 nm gold electrode was fabricated using thermal evaporation deposition (Kurt Lesker, USA). P3 was etched using the same etching parameters as P2. The width of P3 was 41 μm, and the spacing between P1 and P3 was 192 μm, resulting in a geometric fill factor of 96.8%. Figure 9 As shown ( Figure 9 Image A shows the actual perovskite component, and image B shows the P1, P2, and P3 etching lines and their corresponding widths created using laser etching technology.

[0091] Comparative Example 3

[0092] The crystallized perovskite film in Example 2 was replaced with the perovskite film prepared by the anti-solvent method (ASM) in Comparative Example 1, and the rest was the same as in Example 2.

[0093] Comparative Example 4

[0094] The crystallized perovskite film in Example 2 was replaced with the perovskite film prepared by the vacuum-permeable (GPM) method in Comparative Example 2, and the rest was the same as in Example 2.

[0095] The performance of the perovskite modules obtained in Example 2 and Comparative Examples 3-4 was tested, as follows:

[0096] Test 1: Photoelectric Performance of Perovskite Modules

[0097] Current-voltage (IV) testing is commonly used to test and evaluate the device performance of perovskite solar cells. IV testing is typically performed under standard AM (1.5G) sunlight. Through IV curves, four key parameters of the perovskite module can be obtained: short-circuit current (IL), voltage current (IV ... sc ), open circuit voltage (V) oc The test results are as follows: fill factor (FF) and power conversion efficiency (PCE). Figure 10 As shown.

[0098] Figure 10 These are the photoelectric performance statistics (including short-circuit current I) of perovskite modules assembled from perovskite thin films prepared by three different methods in Examples 2 and Comparative Examples 3-4. sc Open circuit voltage V oc Fill factor (FF) and photoelectric conversion efficiency (PCE) Figure 10The corresponding photoelectric performance statistics of the perovskite modules are listed in Table 1. From... Figure 10 As can be seen, the perovskite module obtained by the method of the present invention can significantly improve the photoelectric performance of the perovskite module.

[0099] Table 1. Photoelectric properties of perovskite components assembled from perovskite thin films prepared by three different methods in Examples 2 and Comparative Examples 3-4.

[0100]

[0101]

[0102] Certified by the authoritative Fuzhou Institute of Metrology, the perovskite module assembled from perovskite thin films obtained by the method of this invention achieves a back-scan efficiency of up to 23.46%, and a quasi-steady-state efficiency of up to 22.4% (with an aperture area of ​​26.02 cm²). 2 This is the highest efficiency value for perovskite components at this size, such as... Figure 11 As shown, Figure 11 Figure A shows the certified IV curve and related photoelectric performance parameters, while Figure B shows the certified steady-state curve and corresponding photoelectric performance parameters. The efficiency of this perovskite module is included in the 62nd edition of *Solar Cell Efficiency Tables*. Figure 12 As shown, this remains a world record value.

[0103] Test 2: Encapsulation and Damp Heat Stability Test of Perovskite Modules

[0104] The perovskite module is encapsulated using glass-to-glass encapsulation technology, combined with edge sealing (UV-cured sealant, Three Bond 3035B), and then sealed under UV light irradiation (LED floodlight, DELOLUX 20). First, the edges of the perovskite module are cleaned with a laser, then a 65×70mm... 2 Indium solder was soldered onto the FTO and Au electrodes at the edge of the substrate, and then a 60×65mm substrate was formed. 2 The glass is placed on top of the Au layer of the perovskite module. A UV-cured sealant is deposited on the edges of the glass, completely covering the gap between the top glass and the module. Finally, UV curing is used in a glove box at 25% maximum power to induce crosslinking of the sealant with the glass for 120 seconds, allowing the UV-cured adhesive to fully cure and completing the encapsulation.

[0105] The packaged modules were stored in a constant temperature and humidity chamber (GP / TH-150, SH Guangpin Test Equipment Manufacturing Co., Ltd.) under ambient conditions. The IV of the perovskite module was measured using an electronic system with a 22-bit delta-sigma analog-to-digital converter, and the light intensity was recorded using silicon cell photodiodes. According to the ISOS-L-1 protocol, the MPP variation was tracked using a maximum power point (MPP) tracking algorithm under one day of sunlight, and the results were recorded as a test of the light stability of the perovskite photovoltaic module. The test results are as follows: Figure 13 As shown in Figure A. Furthermore, the packaged perovskite module was stored in a constant temperature and humidity chamber. Following the ISOS-L-3 protocol, the chamber was set to a temperature of 60°C and a relative humidity of 85%. The MPP tracking algorithm was used again to track MPP changes, and the damp heat stability of the perovskite module was tested. The test results are shown in Figure A. Figure 13 As shown in B.

[0106] Depend on Figure 13 It can be seen that the high-quality perovskite thin film prepared by this invention can effectively improve the stability of perovskite components.

[0107] Example 3 1cm 2 Fabrication of high-efficiency perovskite solar cells

[0108] A perovskite thin film with dimensions of 1.5 cm × 6.5 cm was prepared according to the method in Example 1, and then a high-efficiency perovskite solar cell was assembled according to the following method:

[0109] Preparation of spiro-OMeTAD solution for hole transport: Dissolve 105 mg of spiro-OMeTAD in 1343 μL of chlorobenzene, and add 41 μL of tetra-tert-butylpyridine, 25 μL of acetonitrile solution of Li-TFSI (517 mg of Li-TFSI dissolved in 1 mL of acetonitrile solvent), and 19 μL of acetonitrile solution of Co-TFSI (376 mg of Co-TFSI dissolved in 1 mL of acetonitrile solvent). Stir thoroughly for 1–2 hours to obtain spiro-OMeTAD solution.

[0110] Conductive glass pretreatment: Glass with dimensions of 1.5 × 6.5 cm... 2 The FTO substrate was etched using a laser etcher (Trotec, Austria) at 60% laser power, a speed of 300 mm / s, a frequency of 65 kHz, and a pulse width of 120 ns. The laser-etched FTO substrate (Asahi FTO glass, 12-13 Ω / square) was then sequentially cleaned in an ultrasonic bath with a cleaning agent (5% Hellmanex aqueous solution), deionized water, acetone, and isopropanol for 30 minutes each. Finally, the FTO substrate was further cleaned with ultraviolet-ozone (UVO) surface treatment for 15 minutes.

[0111] Perovskite solar cell fabrication:

[0112] Dense TiO2 layers (c-TiO2) and SnO2 layers (c-SnO2) were sequentially deposited on a clean FTO substrate using chemical bath deposition (CBD), following the preparation method described in J. Mater. Chem. A, 2018, 6, 10233-10242. The substrate was then annealed at 190°C for 60 minutes on a hot plate. After cooling, the substrate was treated with UVO for half an hour before use.

[0113] A 5 mg / mL isopropanol solution of phenylethylamine iodide (PEAI) was spin-coated onto the surface of a 1.5 cm × 6.5 cm perovskite film as a passivation layer. Following this, a Spiro-OMeTAD hole transport layer was spin-coated. Finally, a 70 nm gold electrode was fabricated using thermal evaporation deposition (Kurt Lesker, USA).

[0114] Comparative Example 5

[0115] The crystallized perovskite film in Example 3 was replaced with a perovskite film with a size of 1.5 cm × 6.5 cm prepared according to the anti-solvent method (ASM) of Comparative Example 1, and the rest was the same as in Example 3.

[0116] Comparative Example 6

[0117] The crystallized perovskite film in Example 3 was replaced with a 1.5cm × 6.5cm perovskite film prepared by vacuum-permeable (GPM) according to Comparative Example 2, and the rest was the same as in Example 3.

[0118] The performance of the perovskite solar cells obtained in Example 3 and Comparative Examples 5-6 was tested, as follows:

[0119] Test 1: Photovoltaic Performance of Perovskite Solar Cells

[0120] Current density-voltage (JV) testing is commonly used to test and evaluate the device performance of perovskite solar cells. JV testing is typically performed under standard AM (1.5G) sunlight. The JV curve yields four key parameters of the perovskite module: short-circuit current density (JV), voltage density (JV), and voltage level (VV). sc ), open circuit voltage (V) oc ), fill factor (FF) and photoelectric conversion efficiency (PCE).

[0121] Figure 14 Table 2 shows the IV curves of perovskite solar cells prepared by three different methods in Examples 3 and Comparative Examples 5-6, with the corresponding photoelectric performance statistics listed in Table 2. Figure 14As can be seen, the perovskite module obtained by the method of the present invention can significantly improve the V of perovskite solar cells. oc The high efficiency and efficiency of the FF method are mainly attributed to its ability to effectively reduce the inhomogeneity of the thin film and eliminate pores at the buried interface, thereby improving the extraction, transport and collection of photogenerated carriers and suppressing nonradiative recombination of charges at the interface, thus significantly improving the photoelectric performance of the battery.

[0122] Table 2. Photoelectric performance of perovskite solar cells assembled from perovskite thin films prepared by three different methods in Examples 3 and Comparative Examples 5-6.

[0123] ASM 26.35 1.114 77.7 22.81 GMP 26.42 1.124 79.3 23.55 TGMP 26.51 1.163 82.2 25.34

[0124] Test 2: Third-party certification test for perovskite solar cells

[0125] Certified by the authoritative Fuzhou Institute of Metrology, the perovskite solar cell assembled using the method of this invention achieves a back-scan efficiency of up to 25.24% and a quasi-steady-state efficiency of up to 24.62% (pore area of ​​1.047 cm²). 2 This is at 1cm 2 The highest efficiency of perovskite solar cells of various sizes, such as Figure 15 As shown, Figure 15 Figure A shows the certified IV curve and related photoelectric performance parameters, while Figure B shows the certified steady-state curve and corresponding photoelectric performance parameters. This efficiency exceeds the current record of 24.35% recorded in the 62nd edition of *Solar Cell Efficiency Tables*. Figure 12 .

[0126] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An apparatus for preparing perovskite thin films, characterized in that, Includes a sample chamber, which is a sealed chamber formed by a conical cavity (1), a sealing gasket (7), and a base (5); the sealing gasket (7) is a hollow structure with several through holes (8) symmetrically arranged around it to communicate with the atmosphere; the conical cavity (1) is placed on the surface of the sealing gasket (7) and covers the hollow structure; the base (5) is located below the sealing gasket (7); A buffer tank (2) is connected to the conical cavity (1) via a first pipe, and a first valve (4-1) is provided on the first pipe; A vacuum pump (3) is connected to the buffer tank (2) via a second pipe, and a second valve (4-2) is provided on the second pipe; and heating components for heating the sample chamber.

2. The apparatus according to claim 1, characterized in that, The sealing gasket (7) is a silicone gasket; the diameter of the through hole (8) is less than 3 mm, and the number of through holes (8) is 4 to 128.

3. The apparatus according to claim 1, characterized in that, The heating element is a heating platform located below the base (5) or an infrared coil located inside the conical cavity (1).

4. The apparatus according to claim 1, characterized in that, A first pressure gauge (6-1) is installed on the first pipe between the conical cavity (1) and the first valve (4-1); a second pressure gauge (6-2) is installed on the buffer tank (2).

5. A method for preparing perovskite thin films using the apparatus according to any one of claims 1 to 4, characterized in that, Includes the following steps: The pressure inside the buffer tank (2) is pre-evacuated to 0.1-500 Pa using a vacuum pump (3); The heating element is turned on to preheat the sample chamber. The perovskite liquid film is placed in the hollow part of the sealing gasket (7) in the sample chamber, and the liquid level of the perovskite liquid film is level with the center of the through hole (8). Then the first valve (4-1) is opened, and the sample chamber is evacuated into a vacuum. At the same time, the outside atmosphere is ventilated to the sample chamber through the through hole (8). The vacuum pump (3) is always turned on. Under the simultaneous action of evacuation, heating and ventilation, the solvent in the perovskite liquid film is carried away to obtain a perovskite thin film.

6. The method according to claim 5, characterized in that, The heating element is set to a heating temperature of 60–150°C.

7. The method according to claim 5, characterized in that, The simultaneous action time of the air extraction, heating and ventilation is 10s to 10min.

8. The perovskite thin film prepared by the method according to any one of claims 5 to 7.

9. The perovskite thin film according to claim 8, characterized in that, The perovskite thin film has a thickness of 100–2000 nm and an area of ​​2–20000 cm². 2 .

10. A perovskite solar cell module, characterized in that, It includes a substrate, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and an electrode layer, wherein the perovskite light-absorbing layer is the perovskite thin film as described in claim 8 or 9.

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