Perovskite thin film, passivation method and application

Abstract

The invention relates to a perovskite thin film, a passivation method and application, belongs to the technical field of photoelectric functional materials and devices, and aims to solve the problems of low efficiency, poor stability and the like of a solar cell caused by perovskite crystal defects in the prior art. The perovskite thin film passivation method comprises the following steps: adding 1, 4-butane sultone into a perovskite precursor solution to obtain a mixed solution, processing the mixed solution to form a perovskite precursor thin film, and carrying out annealing treatment to obtain the perovskite thin film. By adding BuSO, the nucleation rate of perovskite can be effectively reduced, so that the large-grain and high-quality perovskite thin film is obtained, the BuSO can be subjected to halogen ion induced ring-opening reaction in the annealing process, generated chain ions are distributed on the grain boundary and the surface and act with perovskite, compounding of a bulk phase and an interface is reduced, and the performance of the perovskite thin film is improved. And the efficiency and the long-term stability of the solar cell are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic functional materials and devices, and in particular to a perovskite film and a passivation method and application thereof. Background Art

[0002] Among photovoltaic devices, silicon solar cells have led the way for decades due to their high performance, high stability, and mature technology.

[0003] However, the high energy consumption of silicon solar cells during the production process and the serious pollution to the environment limit their continued development in the energy industry. Therefore, the development of new alternative high-performance solar cells has become one of the most important research topics. Among them, organic / inorganic hybrid perovskites are included as one of the most promising photovoltaic materials as a new material. The rapid progress of perovskite solar cells is attributed to the excellent semiconductor properties of perovskite materials, such as high absorption coefficient and excellent bipolar transport capacity. The band gap width of common perovskite materials is in the range of 1.5 to 2.3 eV, which is the most suitable range for solar cells. In addition, perovskites have high carrier mobility and diffusion length (including both electrons and holes).

[0004] However, during the preparation of perovskites, the ratio of precursor solutions, processing technology and annealing temperature will affect the crystal quality and easily lead to various crystal defects. These defects in perovskite crystals will become carrier non-radiative recombination centers, affecting the carrier transport process, causing mismatched energy level structures between different functional layers, and hindering the performance and stability of perovskite solar cells. Lower defect density can effectively reduce carrier non-radiative recombination. Therefore, passivation of perovskite films has become an indispensable method to improve the efficiency and stability of perovskite solar cells, and is also an effective strategy to reduce defects at grain boundaries and film surfaces. Summary of the invention

[0005] In view of the above analysis, the present invention provides a perovskite film and a passivation method and application to solve the problems of low efficiency and poor stability of solar cells caused by perovskite crystal defects in the prior art.

[0006] In a first aspect, the present invention provides a method for passivating a perovskite film, comprising adding 1,4-butane sultone (BuSO) to a perovskite precursor solution to obtain a mixed solution, processing the mixed solution to form a perovskite precursor film, and annealing to obtain the perovskite film.

[0007] Furthermore, the solvent in the perovskite precursor solution is one or more of N,N-dimethylformamide, dimethyl sulfoxide or N-methylpyrrolidone.

[0008] Furthermore, the concentration of perovskite in the perovskite precursor solution is 1.0-2.0 mol / L.

[0009] Furthermore, the volume of 1,4-butane sultone accounts for 2 to 30% of the volume of the solvent.

[0010] Furthermore, the processing includes one or more of spin coating, scraper coating, slit coating, and inkjet printing on the substrate.

[0011] Furthermore, the method further comprises immersing the perovskite precursor film in an anti-solvent for 1 to 300 seconds and then performing an annealing treatment.

[0012] Furthermore, the anti-solvent includes one or more of alcohols, esters, ethers, nitriles, alkanes, chlorinated hydrocarbons, aromatic hydrocarbons or halogenated aromatic hydrocarbons.

[0013] Furthermore, the annealing temperature is 100-150° C., and the annealing time is 15-90 minutes.

[0014] In a second aspect, the present invention provides a perovskite film prepared by the above method.

[0015] In a third aspect, the present invention provides a solar cell comprising a perovskite film prepared by the above method.

[0016] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0017] (1) The addition of 1,4-butane sultone (BuSO) in the present invention can effectively reduce the nucleation rate of perovskite, thereby obtaining a large-grain, high-quality perovskite film. During the annealing process, 1,4-butane sultone (BuSO) will induce a halogen ion-induced ring-opening reaction, and the generated chain ions are distributed on the grain boundaries and surfaces, interacting with the perovskite, reducing the recombination of the bulk phase and the interface, and effectively improving the efficiency and long-term stability of the solar cell;

[0018] (2) The reaction product of 1,4-butane sultone (BuSO) in the present invention with halogen ions during the annealing process can spontaneously passivate the body and surface of the perovskite film, reduce the defect state concentration in the body and surface of the perovskite, optimize the carrier transport characteristics, reduce the loss of non-radiative recombination ability, and greatly improve the simplicity of the passivation process, making it more suitable for large-scale industrial production of high-efficiency perovskite films;

[0019] (3) The anti-solvent immersion method used in the present invention is more suitable for large-area production. The anti-solvent immersion method replaces the anti-solvent spin coating in the prior art to remove excess solvent in the film and promote the nucleation and growth of perovskite;

[0020] (4) The energy conversion efficiency of the solar cell made of the perovskite film treated by the method of the present invention can reach up to 25.6%.

[0021] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0023] Figure 1 This is a SEM image of the perovskite film prepared by the method of Example 1 of the present invention;

[0024] Figure 2 This is a SEM image of the perovskite film prepared by the method of Comparative Example 1 of the present invention;

[0025] Figure 3 The fluorescence spectra of the perovskite films obtained by the methods of Example 1, Examples 3-4 and Comparative Example 1 of the present invention are shown;

[0026] Figure 4 The time-resolved fluorescence spectra of the perovskite films obtained by the methods of Example 1, Examples 3-4 and Comparative Example 1 of the present invention;

[0027] Figure 5 The NMR images of the product of BuSO after the halogen-induced ring-opening reaction and BuSO in Example 1 of the present invention are shown. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0029] 1,4-Butane sultone in the present invention is hereinafter abbreviated as BuSO.

[0030] A specific embodiment of the present invention discloses a perovskite film passivation method, comprising adding 1,4-butane sultone (BuSO) to a perovskite precursor solution to obtain a mixed solution, processing the mixed solution to form a perovskite precursor film, and annealing to obtain the perovskite film.

[0031] Compared with the prior art, the present invention uses BuSO to treat perovskite, which can effectively reduce the nucleation rate of perovskite, thereby obtaining a large-grain, high-quality perovskite film. During the annealing process, 1,4-butane sultone (BuSO) induces a halogen ion-induced ring-opening reaction, and the generated chain ions are distributed on the grain boundaries and surfaces, and react with the perovskite, thereby reducing the recombination of the bulk phase and the interface, and effectively improving the efficiency and long-term stability of the solar cell.

[0032] The energy conversion efficiency of the solar cell made of the perovskite film processed by the method of the present invention can reach up to 25.6%.

[0033] It should be noted that BuSO can optimize the film-forming properties of perovskite, improve crystal nucleation and growth, and regulate the kinetic process during the formation of perovskite films. The perovskite precursor solution adjusted by BuSO is compatible with preparation processes such as anti-solvent baths, which is more conducive to the preparation of large-area perovskite films.

[0034] The perovskite precursor solutions described in the present invention are all prepared by using existing technologies. The perovskite precursor solutions in the embodiments of the present invention are specifically explained as follows.

[0035] The perovskite precursor solution comprises perovskite and a solvent, wherein the perovskite is an ABX3 type perovskite, wherein A includes but is not limited to an organic cation methylamine (CH3NH3 + ), formamidine (NH2CHNH2 + ), metal cation K + , Cs + or Rb + One or more; B includes but is not limited to Pb 2+ Sn 2+ ,Ge 2+ , Sb 2+ One or more of; X is Cl - Br - ,I - One or more of.

[0036] A preferred embodiment, Cs in A + The molar proportion is 1-10%, which can improve the film forming property and stability of the perovskite film.

[0037] In a specific embodiment, the solvent in the perovskite precursor solution is one or more of N,N-dimethylformamide, dimethyl sulfoxide or N-methylpyrrolidone.

[0038] In a specific embodiment, the concentration of perovskite in the perovskite precursor solution is 1.0-2.0 mol / L, for example, 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.7 mol / L, 1.8 mol / L, 1.9 mol / L, 2.0 mol / L.

[0039] It should be noted that the above-mentioned perovskite concentration can ensure a reasonable perovskite film thickness.

[0040] In a specific embodiment, the volume of 1,4-butane sultone accounts for 2-30% of the volume of the solvent, for example, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%.

[0041] It should be noted that BuSO is used as an additive, and considering its passivation effect and the influence of solvent solubility, the volume is 2-30%, which is a reasonable range. After 1,4-butane sultone is added to the perovskite precursor solution, it is stirred with a magnetic stirrer and then filtered.

[0042] In a specific embodiment, the processing includes one or more of spin coating, scraper coating, slit coating, and inkjet printing on the substrate.

[0043] In a specific embodiment, the perovskite precursor film is immersed in an anti-solvent for 1 to 300 seconds and then annealed, for example, for 1 second, 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, 70 seconds, 80 seconds, 90 seconds, 100 seconds, 110 seconds, 120 seconds, 130 seconds, 140 seconds, 150 seconds, 160 seconds, 170 seconds, 180 seconds, 190 seconds, 200 seconds, 210 seconds, 220 seconds, 230 seconds, 240 seconds, 250 seconds, 260 seconds, 270 seconds, 280 seconds, 290 seconds, or 300 seconds.

[0044] It should be noted that the above-mentioned immersion time can remove the solvent in the perovskite precursor solution and allow the perovskite to undergo preliminary nucleation and crystallization.

[0045] In a specific embodiment, the anti-solvent includes one or more of alcohols, esters, ethers, nitriles, alkanes, chlorinated hydrocarbons, aromatic hydrocarbons or halogenated aromatic hydrocarbons.

[0046] Specifically, the alcohol includes, but is not limited to, one or more of ethanol, isopropanol, n-butanol, isobutanol, isopentanol, and ethylene glycol;

[0047] The esters include but are not limited to one or more of ethyl acetate, methyl acetate, and butyl acetate;

[0048] The ethers include, but are not limited to, one or more of ethyl ether, methyl ethyl ether, n-propyl ether, n-butyl ether, isopropyl ether, anisole, and tetrahydrofuran;

[0049] The nitriles include but are not limited to acetonitrile and / or benzonitrile;

[0050] The alkanes include but are not limited to cyclohexane and / or n-hexane;

[0051] The chlorinated hydrocarbons include but are not limited to chloroform;

[0052] The aromatic hydrocarbons include, but are not limited to, one or more of toluene, o-xylene, and m-xylene;

[0053] Or halogenated aromatic hydrocarbons include but are not limited to one or more of chlorobenzene, o-dichlorobenzene, mesitylene, and trifluoromethylbenzene.

[0054] In a specific embodiment, the annealing temperature is 100-150°C, for example, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, and the annealing time is 15-90 minutes, for example, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 60 minutes, 65 minutes, 70 minutes, 75 minutes, 80 minutes, 85 minutes, 90 minutes.

[0055] It should be noted that during the annealing process, the sultone structure in BuSO can undergo a ring-opening reaction with a nucleophilic reagent.

[0056] Among them, BuSO and Cl - Br - or I - Reaction to generate 4-chlorobutane-1-sulfonic acid anion (Cl-BuSO - ), 4-bromobutane-1-sulfonic acid anion (Br-BuSO - ) or 4-iodobutane-1-sulfonic acid anion (I-BuSO - ), the specific reaction formula is as follows:

[0057]

[0058] Cl-BuSO - , Br-BuSO - and I-BuSO - It can effectively passivate the defect states in the perovskite body and surface, optimize the carrier transport characteristics, reduce the non-radiative recombination energy loss, and effectively improve the efficiency of perovskite solar cells.

[0059] In a second aspect, the present invention provides a perovskite film prepared by the above method.

[0060] In a third aspect, the present invention provides a solar cell comprising a perovskite film prepared by the above method.

[0061] In a preferred embodiment, the structure of the solar cell includes, from bottom to top, a first electrode, a first transmission layer, a perovskite film, a second transmission layer and a second electrode.

[0062] Specifically, the solar cell adopts a forward structure, the first transport layer is a metal oxide electron transport layer, including but not limited to any one of titanium oxide, tin oxide, and zinc oxide. The second transport layer is a hole transport layer, including but not limited to Spiro-OMeTAD, PEDOT-PSS, PTAA, P3HT, nickel oxide (NiO x )

[0063] In a specific embodiment, the solar cell adopts a forward structure, the first transport layer is a hole transport layer, and the second transport layer is an electron transport layer.

[0064] Specifically, the hole transport layer includes but is not limited to Spiro-OMeTAD, PEDOT-PSS, PTAA, P3HT, nickel oxide (NiO x The electron transport layer includes but is not limited to any one of titanium oxide, tin oxide, and zinc oxide.

[0065] The technical solution of the present invention is further explained below in conjunction with specific embodiments.

[0066] Example 1

[0067] A perovskite film passivation method of this embodiment includes the following steps:

[0068] (1) adding 830 mg of lead iodide, 310 mg of formamidine hydroiodide and 42.5 mg of methylamine hydrochloride to N,N-dimethylformamide, stirring and dissolving them uniformly, and then adding BuSO to obtain a mixed solution, wherein the volume ratio of BuSO to N,N-dimethylformamide is 1:10, and the concentration of perovskite in the perovskite precursor solution is 1.8 mol / L;

[0069] (2) dropping the mixed solution onto a substrate, and spin coating the substrate at 5000 rpm for 10 seconds with an acceleration of 3000 rpm to form a perovskite precursor film; soaking the perovskite precursor film in an anti-solvent ether for 10-20 seconds to remove excess solvent N,N-dimethylformamide; and transferring the film to a hot stage for annealing at 120° C. for 60 minutes to obtain a perovskite film.

[0070] Example 2

[0071] A perovskite film passivation method of this embodiment includes the following steps:

[0072] (1) 657 mg of lead iodide, 232 mg of formamidine hydroiodide, 27.5 mg of lead bromide, 19.5 mg of cesium iodide, 8.4 mg of methylamine hydrobromide, and 30.4 mg of methylamine hydrochloride were added to N,N-dimethylformamide, stirred and dissolved uniformly, and then BuSO was added and stirred for 2 hours until completely dissolved, wherein the volume ratio of DMF to BuSO was 10:1, and the concentration of perovskite in the perovskite precursor solution was 1.5 mol / L;

[0073] (2) dropping the mixed solution onto a substrate, and spin coating the substrate at 5000 rpm for 10 seconds with an acceleration of 3000 rpm to form a perovskite precursor film, soaking the perovskite precursor film in an anti-solvent ether for 10-20 seconds to remove excess solvent N,N-dimethylformamide, and then transferring the film to a hot stage, and annealing the film at 120° C. for 45 minutes to obtain a perovskite film.

[0074] Example 3

[0075] The perovskite film passivation method of this embodiment is the same as that of Embodiment 1, except that in step (1), the volume ratio of BuSO to N,N-dimethylformamide is 1:50.

[0076] Example 4

[0077] The perovskite film passivation method of this embodiment is the same as that of Embodiment 1, except that in step (1), the volume ratio of BuSO to N,N-dimethylformamide is 1:4.

[0078] Example 5

[0079] The perovskite film passivation method of this embodiment is the same as that of Embodiment 1, except that the annealing temperature in step (2) is 100° C. and the annealing time is 90 minutes.

[0080] Example 6

[0081] The perovskite film passivation method of this embodiment is the same as that of Embodiment 1, except that the annealing temperature in step (2) is 150° C. and the annealing time is 15 minutes.

[0082] Example 7

[0083] The perovskite film passivation method of this embodiment is the same as that of Embodiment 2, except that the concentration of perovskite in the perovskite precursor solution described in step (1) is 2 mol / L.

[0084] Example 8

[0085] The perovskite film passivation method of this embodiment is the same as that of Embodiment 2, except that the concentration of perovskite in the perovskite precursor solution described in step (1) is 1 mol / L.

[0086] Comparative Example 1

[0087] The perovskite film passivation method of this comparative example is the same as that of Example 1, except that in step (1), BuSO is not added.

[0088] Test Example 1

[0089] The SEM images of the perovskite films prepared in Example 1 and Comparative Example 1 were tested respectively. Figure 1 and 2 As shown, from Figure 1 and 2 It can be seen that the introduction of BuSO increases the grain size, the grain size is above 2 nanometers on average, improves the film morphology, and improves the film quality.

[0090] Test Example 2

[0091] The fluorescence spectra PL and time-resolved fluorescence spectra TRPL of the perovskite films obtained by the methods of Example 1, Examples 3-4 and Comparative Example 1 were tested respectively. Figure 3 and 4 shown.

[0092] from Figure 3 and 4 It can be seen that the film with the addition of BuSO exhibits stronger fluorescence emission and longer fluorescence lifetime, indicating that the defects in the bulk phase and grain boundaries are reduced, non-radiative recombination is suppressed, and the film quality is greatly improved.

[0093] Test Example 3

[0094] The NMR images of the product of the halogen-induced ring-opening reaction of BuSO in Test Example 1 and BuSO are as follows: Figure 5 As shown, it can be seen from the figure that the reaction in the present invention occurs.

[0095] Application Example 1

[0096] The device structure is prepared from bottom to top: FTO / tin oxide / FAPbI3 perovskite / Spiro-OMeTAD / MoO x / Ag forward perovskite solar cells

[0097] The FAPbI3 perovskite in this application example is a perovskite film prepared by the method of Example 1.

[0098] The specific preparation method of the solar cell of this application example is as follows:

[0099] (1) Cleaning of FTO glass substrate: FTO was ultrasonically cleaned with cleaning solution, deionized water, acetone, and isopropanol for 20 minutes respectively. The cleaned FTO substrate was immersed in isopropanol for later use, dried with nitrogen, and treated with UVO for 30 minutes for later use;

[0100] (2) Preparation of SnO2 electron transport layer: The SnO2 electron transport layer was prepared by spin coating SnO2 nanoparticles (AlfaAesar, 15% aqueous dispersion). The SnO2 nanoparticle stock solution was diluted in a ratio of 1:1 between the stock solution and water, and the diluted SnO2 solution was spin coated on the FTO (speed 3000 rpm, time 30 seconds), and then the substrate was moved to a hot stage for annealing (annealing temperature 150 degrees, annealing time 30 minutes), and UVO treated for 30 minutes before use.

[0101] (3) Preparation of FAPbI3 perovskite film: The method is the same as that in Example 1 and is prepared on a FTO / SnO2 substrate.

[0102] (4) Preparation of Spiro-OMeTAD hole transport layer: Preparation of Spiro-OMeTAD solution: 90 mg of Spiro-OMeTAD was dissolved in 1 ml of chlorobenzene, followed by the addition of 39 μl of 4-tert-butylpyridine, 22 μl of LiTFSI acetonitrile solution (520 mg / ml) and 12 μl of FK209 acetonitrile solution (300 mg / ml). After mixing well, the mixture was spin-coated at 5000 rpm for 30 s.

[0103] (5) Preparation of Ag electrode: Ag electrode was prepared by evaporation method with a thickness of 100 nm.

[0104] The solar cell obtained in this application example is tested at AM1.5G, 100mW / cm 2 The photovoltaic performance parameters under illumination conditions are shown in Table 1.

[0105] Table 1

[0106]

[0107] Application Example 2

[0108] The device structure is FTO / PACz / Cs from bottom to top. 0.05 MA 0.05 FA 0.9 Pb(I 0.95 Br 0.05 )3 Perovskite / C60 / BCP / Ag reverse perovskite solar cell

[0109] In this application example, Cs 0.05 MA 0.05 FA 0.9 Pb(I 0.95 Br 0.05 )3 Perovskite: A perovskite film prepared by the method of Example 2.

[0110] The specific preparation method of the solar cell of this application example is as follows:

[0111] (1) Cleaning of FTO glass substrate: FTO was ultrasonically cleaned with cleaning solution, deionized water, acetone, and isopropanol for 20 minutes respectively. The cleaned FTO substrate was immersed in isopropanol for later use, dried with nitrogen, and treated with UVO for 30 minutes for later use;

[0112] (2) Preparation of PACz monolayer. 40 μL of 0.3 mg / mL PACz ethanol was dropped on the FTO substrate and spin-coated at 3000 rpm for 30 seconds. The glass substrate was then transferred to a hot stage and annealed at 100°C for 10 minutes and cooled to room temperature for later use.

[0113] (3) Cs 0.05 MA 0.05 FA 0.9 Pb(I 0.95 Br 0.05 )3 Preparation of perovskite film: The method is the same as that in Example 2, and is prepared on a FTO / PACz substrate;

[0114] (4) Preparation of C60 electron transport layer, BCP transition layer, and Ag electrode: The C60 electron transport layer, BCP transition layer, and Ag electrode were prepared by evaporation, with thicknesses of 25 nm, 8 nm, and 100 nm, respectively.

[0115] The solar cell obtained in this application example is tested at AM1.5G, 100mW / cm 2 The photovoltaic performance parameters under illumination conditions are shown in Table 2.

[0116] Table 2

[0117]

[0118] Application Example 3

[0119] The preparation method of the solar cell in this application example is the same as that in the application example, except that the perovskite film is prepared by the method of comparative example 1.

[0120] The solar cell obtained in this comparative example was tested at AM1.5G, 100mW / cm 2 The photovoltaic performance parameters under illumination conditions are shown in Table 3.

[0121] Table 3

[0122]

[0123] As can be seen from Table 3, compared with Application Example 3, Application Example 1 has a higher open circuit voltage and fill factor, thus showing a higher device efficiency, which shows that the addition of BuSO can effectively improve the device efficiency. On the one hand, due to the regulation of the crystallization process by BuSO, the grain size increases; on the other hand, the product of the BuSO ring-opening reaction can effectively passivate the defects in the film. In summary, the introduction of BuSO can greatly improve the quality of the perovskite film, thereby obtaining a more efficient perovskite solar cell device.

[0124] The inventor has also conducted the above test on other embodiments, and the results are basically the same. Due to limited space, they are not listed one by one.

[0125] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A perovskite film passivation method, characterized in that: The method comprises adding 1,4-butane sultone into a perovskite precursor solution to obtain a mixed solution, processing the mixed solution to form a perovskite precursor film, and annealing to obtain the perovskite film.

2. The perovskite film passivation method according to claim 1, characterized in that: The solvent in the perovskite precursor solution is one or more of N,N-dimethylformamide, dimethyl sulfoxide or N-methylpyrrolidone.

3. The perovskite film passivation method according to claim 1, characterized in that: The concentration of perovskite in the perovskite precursor solution is 1.0-2.0 mol / L.

4. The perovskite film passivation method according to claim 2, characterized in that: The volume of 1,4-butane sultone accounts for 2 to 30% of the volume of the solvent.

5. The perovskite film passivation method according to claim 1, characterized in that: The processing includes one or more of spin coating, scraper coating, slit coating, and inkjet printing on the substrate.

6. The perovskite film passivation method according to claim 1, characterized in that: The method also includes soaking the perovskite precursor film in an anti-solvent for 1 to 300 seconds and then performing annealing treatment.

7. The perovskite film passivation method according to claim 6, characterized in that: The anti-solvent includes one or more of alcohols, esters, ethers, nitriles, alkanes, chlorinated hydrocarbons, aromatic hydrocarbons or halogenated aromatic hydrocarbons.

8. The perovskite film passivation method according to any one of claims 1 to 7, characterized in that: The annealing temperature is 100 to 150° C., and the annealing time is 15 to 90 minutes.

9. A perovskite film prepared by the method according to any one of claims 1 to 8.

10. A solar cell, characterized in that: A perovskite film prepared by the method of any one of claims 1-8.

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