Perovskite film reaction rate regulation and homogenization processing method based on two-step method

Abstract

The invention relates to the field of perovskite photoelectric material preparation, in particular to a perovskite thin film reaction rate regulation and homogenization processing method based on a two-step method, and the method comprises the following steps: S1, forming a halide thin film on a transmission layer; s2, laser is adopted to carry out at least one of material reduction treatment or material increase treatment on the halide film, the material reduction treatment comprises laser etching to form a periodic micro-nano groove structure, and the material increase treatment comprises laser-induced deposition of an active composite layer; and S3, depositing an organic film on the processed halide film, and annealing to form the perovskite light absorption layer. In order to solve the technical problems that in a two-step method, a halide layer and an organic cation solution interface are not uniform in reaction, the rate is difficult to control and the film forming quality is poor, the laser material reduction and material increase manufacturing technology is innovatively combined, thin film performance optimization is achieved through multi-parameter cooperative regulation and control, and defect passivation and directional construction of a carrier transmission channel are achieved.

Description

Technical Field

[0001] The present invention relates to the field of perovskite optoelectronic material preparation, and particularly to a method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method. Background Art

[0002] Due to the crisis of the increasingly scarce fossil energy and the aggravated environmental pollution, it is a necessary measure to develop clean and renewable new energy, and solar cells can directly utilize the rich solar energy, which is a clean energy source. In recent years, perovskite solar cells have developed rapidly as a new type of thin film battery. The main reason is that the unique crystal structure of perovskite materials endows them with many excellent properties, such as high efficiency limit, good optoelectronic properties, long carrier lifetime, high carrier mobility, solution processability and low preparation cost, etc. Therefore, they have received extensive attention from researchers worldwide. As the third-generation solar cells of the new generation - perovskite solar cells, after more than a decade of development, the highest certified photoelectric conversion efficiency of single-junction cells has reached 26.8% at present.

[0003] Currently, the methods for preparing perovskite films can be roughly divided into: one-step method and two-step method. The one-step method directly mixes the required raw materials for reaction, and under specific conditions, such as appropriate temperature, pressure, solvent, etc., the reaction directly generates perovskite thin films in one step. However, it has disadvantages such as being sensitive to reaction conditions and poor repeatability, which limits large-scale industrial production. The two-step method generally first prepares a halide layer, and then prepares an organic layer on the halide layer to insert an organic salt to form perovskite crystals. Although it can more precisely control the proportion and distribution of each element in the perovskite material, there is still a difficulty in the complete reaction between inorganic metal ions and organic cations. Therefore, it limits the preparation of large-area perovskite thin films by the two-step method.

[0004] Laser has the characteristics of good directivity, high energy and power, and strong operability. In terms of directivity, the divergence angle of the laser beam is small, which can be accurately focused and propagated over a long distance, and can be used for precise processing operations; in terms of power and energy, the laser can concentrate high energy and high power in a small space; in terms of operability, lasers with different wavelengths and powers can be selected to precisely process the film layer.

[0005] The key point of the two-step method for preparing a homogenized perovskite film is to ensure that there are more and more uniform reaction sites on the halide film, so as to promote the better reaction of the organic salt. Therefore, combined with the characteristics of good laser directivity, high energy power, and strong operability, subtractive or additive manufacturing technology can be used for the halide layer, and the film performance can be optimized through multi-parameter collaborative regulation: a lead halide film is etched with a laser with adjustable wavelength, power density, and pulse width to form periodic micro-nano grooves, significantly increasing the interface contact area, and the surface roughness is precisely controlled by the scanning rate and the spot overlap rate, so as to achieve the subtractive goal; similarly, laser-induced chemical deposition with variable wavelength and power density is used to in-situ generate an active composite layer in the etched area, realizing defect passivation and the directional construction of carrier transport channels, achieving the additive purpose. Overcome the difficulties of uneven interface reaction, difficult rate control, and poor film-forming quality between the halide layer and the organic cation solution in the two-step method.

[0006] The information disclosed in this background art section is only intended to deepen the understanding of the overall background art of the present invention, and should not be regarded as an admission or an implication in any form that this information constitutes the prior art known to those skilled in the art. Summary of the Invention

[0007] The technical problem to be solved by the present invention is: aiming at the technical problems of uneven interface reaction, difficult rate control, and poor film-forming quality between the halide layer and the organic cation solution in the two-step method.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is: A method for regulating the reaction rate and homogenizing the processing of a perovskite film based on the two-step method, comprising the following steps: S1 Form a halide film on the transport layer; prepare it by solution method or vapor deposition to form a uniform crystal layer on the surface of the transport layer. The key to this step is to control the crystal orientation and defect density of the film. The crystallization quality of the halide film directly affects the insertion reaction efficiency of the subsequent organic amine salt.

[0009] S2 Perform at least one of subtractive treatment or additive treatment on the halide film with a laser. The laser subtractive treatment locally heats the halide film with a high-energy laser beam to make it sublimate or melt, forming a periodic micro-nano groove structure. The additive treatment uses laser-induced chemical reaction to deposit an active composite layer (such as CsPbX3 quantum dots) in the etched area. This step optimizes the surface morphology and interface characteristics of the film through physical and chemical dual effects.

[0010] S3 deposits an organic thin film on the processed halide thin film and forms a perovskite light-absorbing layer through annealing. The organic ammonium salt solution (such as FAI) diffuses on the surface of the laser-treated halide thin film and undergoes a solid-phase reaction with the halide through a thermal annealing process to form perovskite crystals. During the annealing process, organic ammonium ions are inserted into the halide lattice to complete the construction of the perovskite structure.

[0011] In the present invention, laser treatment significantly improves the specific surface area and reactivity of the halide thin film, enabling the organic ammonium salt to penetrate and react more uniformly, reducing the residue of unreacted PbI2. Laser subtractive treatment is mainly applied to the ready-made lead halide thin film, which can match the existing process route for preparing lead halide thin films and perform periodic micro-nano structure treatment on the lead halide thin film; it can provide more reaction sites, improve the insertion efficiency of the organic ammonium salt, and then guide the orderly diffusion of organic ammonium ions, reduce the reaction activation energy, thereby improving the reaction rate and film uniformity. Laser additive mainly induces the formation of a porous composite active layer of PbI2-xBrx or CsPbX3 from the PbI2-xBrx or CsPbX3 precursor, which can enhance the carrier transport ability of the thin film and provide defect passivation at the same time, reducing the interfacial recombination loss.

[0012] Preferably, the subtractive treatment uses a laser with a wavelength of 400 - 1064 nm, a power density of 10 - 50 MW / cm², a pulse width of 1 - 100 ps, a scanning rate of 100 - 500 mm / s, and a spot overlap rate of 30 - 80% to ensure the formation of periodic micro-nano trenches with a width < 1 mm, a depth of 10 - 500 nm, and a spacing of 1 - 5 mm. Specifically, the wavelength of 400 - 1064 nm can match the light absorption characteristics of PbI2 to ensure the efficient conversion of laser energy into heat energy and achieve precise etching. The power density of 10 - 50 MW / cm 2 exceeds the sublimation threshold of PbI2 but is lower than the substrate damage threshold to ensure etching accuracy and substrate integrity.

[0013] Preferably, the additive treatment uses a continuous / pulsed laser with a wavelength of 200 - 532 nm and a power density of 5 - 30 MW / cm² to induce the formation of an active composite layer containing PbI 2-X Br X or CsPbX3, where X is at least one of Cl, Br, and I, to ensure the formation of a porous thin film structure of perovskite that can react with the organic salt. Specifically, the short-wavelength laser (200 - 532 nm) excites the photolysis reaction of the halide to generate active sites and promote the formation of the composite layer. The PbI 2-X Br X or CsPbX3 composite layer matches the main lattice, reduces the interfacial stress, and improves the mechanical stability of the thin film.

[0014] Preferably, in S1, the halide film is formed by spin coating, blade coating, slot die coating or evaporation, and the film thickness is controlled to be 100 - 500 nm, which can match the carrier diffusion length, reduce the bulk recombination loss, and improve the collection efficiency of photo-generated carriers. The annealing temperature is 50 - 100 °C, and the annealing time is 30 - 60 s. Low-temperature annealing can inhibit the decomposition of the organic transport layer, extend the device life, the film thickness gradient design matches the light field distribution, improve the light absorption efficiency, and the uniform crystal orientation reduces the grain boundary defects and improves the carrier mobility.

[0015] Preferably, in S3, the organic film is obtained by spin coating, blade coating an organic amine salt solution or evaporating an organic compound, realizing uniform film formation and ensuring the sufficient reaction between organic amine ions and halides.

[0016] Preferably, when using an organic amine salt solution, the organic amine salt solution contains at least two mixtures of formamidinium hydroiodide (FAI), methylammonium bromide (MABr), cesium iodide (CsI), methylamine iodide (MAI), etc. The mixed organic amine salt realizes the uniform distribution of A-site cations, improves the stability of the perovskite film, the solution concentration is 0.5 - 1.5 mol / L, which is close to the critical nucleation concentration, controls the crystallization rate, and reduces the grain boundary defects; the spin coating speed of 500 - 2000 rpm can optimize the film thickness and uniformity, and improve the optoelectronic performance of the device; When using an evaporated organic compound, the organic compound is selected from at least one of dimethylammonium iodide (DMAI), methylamine gas (MA0), etc. By gas-phase insertion between the halide layers, a stable perovskite structure is formed, the evaporation rate is 0.1 - 0.5 nm / s, which matches the step-flow growth mode, reduces the surface roughness, improves the interface quality, and the substrate temperature is 80 - 120 °C, which is used to optimize the diffusion and reaction of the organic compound and reduce the defect density.

[0017] The second object of the present invention is: to provide a perovskite solar cell using the perovskite film prepared by the above method as the perovskite light-absorbing layer. By treating the halide film and regulating the uniformity of the organic salt reaction sites in the two-step method, a highly efficient and stable perovskite solar cell can be prepared.

[0018] To achieve the above object, the technical solution adopted by the present invention is: A perovskite solar cell, the cell sequentially includes: a substrate, a hole transport layer or an electron transport layer, a perovskite light-absorbing layer, an electron transport layer or a hole transport layer, a buffer layer, and an electrode layer.

[0019] A preparation method of a perovskite solar cell, comprising the following steps: A hole transport layer (HTL) or an electron transport layer (ETL) is obtained by physically / chemically depositing, chemically bath depositing, or spin-coating a hole transport layer precursor solution (inverted structure) / electron transport layer precursor solution (normal structure) on a substrate. A halide film is prepared on the hole transport layer or the electron transport layer by a solution method or a vapor deposition method. The halide film is subjected to an additive or subtractive process using a laser to form a periodic structure. An organic film is deposited on the processed halide film and annealed to obtain a perovskite light-absorbing layer. An electron transport layer (inverted structure) or a hole transport layer (normal structure), a buffer layer, and an electrode layer are sequentially prepared on the perovskite light-absorbing layer.

[0020] The beneficial effects of the present invention are as follows: Aiming at the technical problems of uneven interfacial reaction, difficult rate control, and poor film-forming quality at the interface between the halide layer and the organic cation solution in the two-step method, the present invention innovatively combines laser subtractive and additive manufacturing technologies, and realizes the optimization of film performance through multi-parameter collaborative regulation: for subtractive manufacturing, a lead halide film is etched with a laser with adjustable wavelength, power density, and pulse width to form periodic micro-nano grooves, significantly improving the interfacial contact area, and precisely controlling the surface roughness through the scanning rate and the spot overlap rate; for additive manufacturing, a variable wavelength and power density laser-induced chemical deposition is used to in-situ generate an active composite layer in the etched area to achieve defect passivation and the directional construction of carrier transport channels. Further, by dynamically optimizing the laser parameter combination (wavelength switching, power gradient, pulse frequency), the reaction activation energy is regulated to decrease, and the residual stress distribution is adjusted. The perovskite film prepared by this method reaches a photoelectric conversion efficiency (AM1.5G) of >23% and >21% under the areas of 0.07 cm 2 and 1 cm 2 respectively, and is compatible with the roll-to-roll process, and can be extended to multi-component systems such as CsPbI3 and FAPbBr3, providing a general solution for the manufacture of high-efficiency large-area photovoltaic devices. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a physical picture of the morphology of the halide film processed with different laser powers in Embodiment 1 of the present application. Figure 2 It is a physical picture of the morphology of the halide film processed with different laser powers in Embodiment 2 of the present application. Figure 3 It is a physical image of the morphology of halide films treated with different laser powers in Example 3 of this application; Figure 4 It is a current density-voltage curve graph of perovskite photovoltaic cells provided in Comparative Example 1 and Examples 1-3 of this application; Figure 5 It is a statistical chart of the short-circuit current density of perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3 of this application, Figure 6 It is a statistical chart of the open-circuit voltage of perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3 of this application, Figure 7 It is a statistical chart of the fill factor of perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3 of this application, Figure 8 It is a statistical chart of the photoelectric conversion efficiency of perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3 of this application; Figure 9 It is a current density-voltage curve graph of large-area perovskite photovoltaic cells prepared in Comparative Example 1 and Example 2 of this application; Detailed implementation manners

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings and the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without making creative efforts shall fall within the scope of protection of this application.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this invention belongs. The terms used in the specification of this invention are only for the purpose of describing specific embodiments and are not intended to limit this invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0025] A method for regulating the reaction rate and homogenizing the processing of perovskite films based on a two-step method, comprising the following steps: S1 Form a halide film on the transport layer; the halide film is formed by spin coating, blade coating, slot die coating, or evaporation, the film thickness is controlled to be 100-500 nm, the annealing temperature is 50-100 °C, and the annealing time is 30-60 s.

[0026] S2 uses a laser to perform at least one of subtractive or additive processing on the halide film. The subtractive processing includes laser etching to form a periodic micro-nano groove structure, and the additive processing includes laser-induced deposition of an active composite layer; S3 deposits an organic film on the processed halide film and anneals it to form a perovskite light-absorbing layer; the organic film is obtained by spin-coating, blade-coating an organic amine salt solution, or evaporating an organic compound; when using an organic amine salt solution, the organic amine salt solution contains at least two mixtures of formamidinium hydroiodide (FAI), methylammonium bromide (MABr), and cesium iodide (CsI), the solution concentration is 0.5 - 1.5 mol / L, and the spin-coating speed is 500 - 2000 rpm; when using an evaporated organic compound, the organic compound is selected from at least one of dimethylammonium iodide (DMAI) and methylamine gas (MA0), the evaporation rate is 0.1 - 0.5 nm / s, and the substrate temperature is 80 - 120 °C.

[0027] The subtractive processing uses a laser with a wavelength of 400 - 1064 nm, a power density of 10 - 50 MW / cm², a pulse width of 1 - 100 ps, a scanning rate of 100 - 500 mm / s, and a spot overlap rate of 30 - 80% to ensure the formation of periodic micro-nano grooves with a width < 1 mm, a depth of 10 - 500 nm, and a pitch of 1 - 5 mm.

[0028] The additive processing uses a continuous / pulsed laser with a wavelength of 200 - 532 nm and a power density of 5 - 30 MW / cm² to induce the formation of an active composite layer containing PbI 2-X Br X or CsPbX3, where X is at least one of Cl, Br, and I, to ensure the formation of a porous film structure of perovskite that can react with the organic salt.

[0029] Taking the inverted structure as an example, a perovskite solar cell sequentially includes: a substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, a buffer layer, and an electrode layer.

[0030] A method for preparing a perovskite solar cell includes the following steps: Spin-coat a hole transport layer precursor solution on the substrate and anneal it to obtain a hole transport layer; Prepare a halide film on the hole transport layer; Use a laser to perform specific patterning on the halide film; Deposit an organic film on the patterned halide film and anneal it to obtain a perovskite light-absorbing layer; Evaporate an electron transport layer and an electrode layer in sequence on the perovskite light-absorbing layer.

[0031] The large-area perovskite photovoltaic cell provided by this application can be prepared at low temperature through wet process, dry process, etc. The operation process is simple and the cost is low. It has good repeatability for large area and is suitable for industrial production.

[0032] In a preferred embodiment, before spin-coating the hole transport layer precursor solution on the substrate, it further includes a pretreatment operation: The substrate is ultrasonically cleaned in an ultrasonic cleaner with deionized water containing glass cleaner and ethanol for 15 minutes respectively. After ultrasonic cleaning, it is dried with nitrogen to obtain a clean substrate.

[0033] Specifically, the substrate uses a fluorine-doped tin oxide substrate.

[0034] Specifically, "spin-coating the hole transport layer precursor solution on the substrate, annealing to obtain the hole transport layer" specifically includes: spin-coating the hole transport layer precursor solution on the substrate, with a spin-coating speed of 3000 - 6000 r.m.p, a spin-coating time of > 20 s. After spin-coating, anneal at > 100 °C for more than 10 minutes to obtain the hole transport layer.

[0035] Specifically, "preparing a halide film on the hole transport layer" specifically includes: preparing a halide film on the hole transport layer, with a spin-coating speed of 500 - 2000 r.m.p, a spin-coating time of > 20 s. After spin-coating, anneal at 50 - 100 °C for 30 - 60 s to obtain the halide film.

[0036] Specifically, "using a laser to perform specific patterning on the halide film" specifically includes: using a laser with a specific wavelength and power to perform patterning on the halide film to obtain a patterned halide film.

[0037] Specifically, "depositing an organic film on the patterned halide film, annealing to obtain the perovskite light-absorbing layer" specifically includes: coating an organic salt solution on the patterned halide film, with a spin-coating speed of 500 - 2000 rmp, a spin-coating time of > 20 s. After spin-coating, anneal in an air atmosphere at 100 - 150 °C for 20 minutes to obtain the perovskite layer.

[0038] Specifically, "successively evaporating an electron transport layer and an electrode layer on the perovskite light-absorbing layer" specifically includes: using thermal evaporation of fullerene or spin-coating of fullerene derivatives to form a fullerene layer; vacuum thermally evaporating 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline or using atomic layer deposition of tin oxide (ALD-SnO2) on the surface of the fullerene layer to form a 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline layer or a dense SnO2; vacuum thermally evaporating Ag, Au or Cu on the surface of the 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline layer or SnO2 to form an electrode layer.

[0039] Example 1 The halide thin film is prepared by using a spin coating speed of 500 - 2000 r.m.p, a spin coating time of >20 s. After spin coating, it is annealed at 50 - 100 °C for 30 - 60 s, and the halide thin film is obtained by performing a subtractive process on the halide thin film with a wavelength of 532 nm, a frequency of 2 kHz, and a power of 1 W.

[0040] Example 2 The halide thin film is prepared by using a spin coating speed of 500 - 2000 r.m.p, a spin coating time of >20 s. After spin coating, it is annealed at 50 - 100 °C for 30 - 60 s, and the halide thin film is obtained by performing a subtractive process on the halide thin film with a wavelength of 532 nm, a frequency of 2 kHz, and a power of 3 W.

[0041] Example 3 The halide thin film is prepared by using a spin coating speed of 500 - 2000 r.m.p, a spin coating time of >20 s. After spin coating, it is annealed at 50 - 100 °C for 30 - 60 s, and the halide thin film is obtained by performing a subtractive process on the halide thin film with a wavelength of 532 nm, a frequency of 2 kHz, and a power of 5 W.

[0042] Comparative Example 1 The halide thin film is prepared by using a spin coating speed of 500 - 2000 r.m.p, a spin coating time of >20 s. After spin coating, it is annealed at 50 - 100 °C for 30 - 60 s.

[0043] Performance Test The devices prepared in Examples 1 - 3 and Comparative Example 1 are subjected to a series of optoelectronic tests using a solar simulator test system. The effective area of the device is 0.07 cm 2 under the test conditions.

[0044] See Figures 1 to 3 As shown, it is a physical image of the morphology of the halide thin films treated with different laser powers in Examples 1 - 3 of the present application; for example, in the laser subtractive process, the control of the power can achieve the regulation of the periodic micro - nano structures.

[0045] See Figure 4 As shown, Figure 4 It is the current density - voltage curve graph of the perovskite photovoltaic cells provided in Comparative Example 1 and Examples 1 - 3 of the present application; it is verified that different periodic micro - nano structures have a certain influence on the photovoltaic parameters of the photovoltaic cells.

[0046] Figures 5 to 8 It is a performance statistical chart of the narrow - bandgap perovskite photovoltaic cells provided in Comparative Example 1 and Examples 1 - 3 of the present application. Among them, Figure 5Shows the statistical chart of the short-circuit current density of the narrow-bandgap perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3. Figure 6 Shows the statistical chart of the open-circuit voltage of the narrow-bandgap perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3. Figure 7 Shows the statistical chart of the fill factor of the narrow-bandgap perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3. Figure 8 Shows the statistical chart of the photoelectric conversion efficiency of the narrow-bandgap perovskite photovoltaic cells prepared in Comparative Example 1 and Examples 1-3; verifying that the photovoltaic cells prepared by laser-treating the lead halide film have repeatability.

[0047] See Figure 9 as shown Figure 9 Is the current density-voltage curve graph of the large-area perovskite photovoltaic cell prepared in Example 2; verifying that the laser-treated lead halide film has the potential to be extended to a large area.

[0048] The raw materials or reagents used in the examples and / or comparative examples of the present invention are all purchased from mainstream manufacturers in the market. Those without indicating the manufacturer or concentration are all raw materials or reagents of analytical purity grade that can be obtained conventionally. As long as they can play the expected role, there is no special limitation. The instruments and equipment used in this example are all purchased from major manufacturers in the market. As long as they can play the expected role, there is no special limitation. For those not indicating the specific technology or conditions in this example, they are carried out according to the technology or conditions described in the literature in this field or according to the product manual.

[0049] Those skilled in the art of this industry should understand that the present invention is not limited by the above-mentioned examples. What is described in the above-mentioned examples and the specification only illustrates the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method, characterized in that, Including the following steps: S1: Form a halide film on the transport layer; S2: Perform at least one of subtractive processing or additive processing on the halide film using a laser. The subtractive processing includes laser etching to form a periodic micro-nano groove structure, and the additive processing includes laser-induced deposition of an active composite layer; S3: Deposit an organic film on the processed halide film and anneal to form a perovskite light-absorbing layer.

2. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method according to claim 1, characterized in that, The subtractive processing is used for lead halide films to perform periodic micro-nano structure processing on lead halide films; the additive processing is used to induce the formation of a PbI2-xBrx or CsPbX3 porous composite active layer from a PbI2-xBrx or CsPbX3 precursor.

3. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method according to claim 2, characterized in that, The subtractive processing uses a laser with a wavelength of 400 - 1064 nm, a power density of 10 - 50 MW / cm², a pulse width of 1 - 100 ps, a scanning rate of 100 - 500 mm / s, and a spot overlap rate of 30 - 80% to form periodic micro-nano grooves with a width < 1 mm, a depth of 10 - 500 nm, and a spacing of 1 - 5 mm.

4. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method according to claim 2, characterized in that The additive processing uses a continuous / pulsed laser with a wavelength of 200 - 532 nm and a power density of 5 - 30 MW / cm² to induce the formation of an active composite layer containing PbI2-xBrx or CsPbX3, where X is at least one of Cl, Br, and I, and react with an organic salt to form a porous film structure of perovskite.

5. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method according to claim 1, characterized in that, In S1, the halide film is formed by spin coating, blade coating, slot die coating, or evaporation, the film thickness is controlled to be 100 - 500 nm, the annealing temperature is 50 - 100 °C, and the annealing time is 30 - 60 s.

6. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method according to claim 1, characterized in that In S3, the organic film is obtained by spin coating, blade coating an organic amine salt solution, or evaporating an organic compound.

7. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method, as claimed in claim 6, wherein When using an organic amine salt solution, the organic amine salt solution contains at least two mixtures of formamidinium hydroiodide, methylammonium bromide, cesium iodide, and methylammonium iodide, the solution concentration is 0.5 - 1.5 mol / L, and the spin coating speed is 500 - 2000 rpm.

8. A method for regulating the reaction rate and homogenizing the processing of perovskite thin films based on a two-step method according to claim 6, characterized in that, When using an evaporated organic compound, the organic compound is selected from at least one of dimethylammonium iodide and methylamine gas, the evaporation rate is 0.1 - 0.5 nm / s, and the substrate temperature is 80 - 120 °C.

9. A perovskite solar cell, characterized in that, Using the perovskite film prepared by the method according to any one of claims 1 - 8 as the perovskite light-absorbing layer, the battery sequentially includes: a substrate, a hole transport layer or an electron transport layer, a perovskite light-absorbing layer, an electron transport layer or a hole transport layer, a buffer layer, and an electrode layer.

10. The preparation method of a perovskite solar cell according to claim 9, characterized in that, Including the following steps: Spin coat a hole transport layer precursor solution or an electron transport layer precursor solution on a substrate and anneal to obtain a hole transport layer or an electron transport layer; Prepare a halide film on the hole transport layer or the electron transport layer; Use a laser to perform additive or subtractive processing on the halide film to form a periodic structure; Deposit an organic film on the processed halide film and anneal to obtain a perovskite light-absorbing layer; Sequentially prepare an electron transport layer or a hole transport layer, a buffer layer, and an electrode layer on the perovskite light-absorbing layer.

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