Preparation method of perovskite precursor solution and anti-radiation perovskite film

Abstract

The application provides a preparation method of a perovskite precursor solution and an anti-radiation perovskite film, and belongs to the technical field of perovskite materials, and comprises the following steps: sequentially adding FAI, SnI2, SnF2 and EDAI2 into a usnic acid / alpha-tocopherol solution, magnetically stirring, then adding 1,4-divinyl perfluorobutane and AIBN and continuing to stir, ultrasonic treatment, and filtration to obtain the perovskite precursor solution; dropping an arginine-PEDOT:PSS solution on a pretreated ITO substrate, spin coating, annealing treatment, cooling, further dropping the perovskite precursor solution for spin coating, dropping anhydrous chlorobenzene during spin coating, performing annealing treatment under a nitrogen atmosphere after spin coating is completed, and cooling to room temperature to obtain the anti-radiation perovskite film. The application can reduce defects and non-radiation recombination while improving the stability of the film under radiation conditions.

Description

Technical Field

[0001] This invention relates to the field of perovskite materials technology, specifically to a method for preparing a perovskite precursor solution and a radiation-resistant perovskite thin film. Background Technology

[0002] Perovskite solar cells (PSCs), as representatives of third-generation solar cells, have attracted attention due to their relatively simple fabrication process, high material utilization, low cost potential, and rapid improvement in power conversion efficiency. The working mechanism of PSCs is generally as follows: under illumination, the perovskite light-absorbing layer absorbs photons to generate electron-hole pairs, which dissociate to form free charge carriers. Electrons are transported towards the cathode and collected by the electron transport layer, while holes are transported towards the anode and collected by the hole transport layer, thus creating a potential difference in the external circuit and outputting current. Thanks to the high absorption coefficient, tunable bandgap, long carrier lifetime, and superior charge transport characteristics of organic-inorganic halide perovskite materials, the power conversion efficiency of PSCs has been improved to over 25%, demonstrating promising application prospects.

[0003] In perovskite solar cells, the perovskite thin film serves as the core light absorption and carrier generation / transport layer. Its film quality (such as crystallinity, density, defect state density, and interface uniformity) directly determines the photogenerated carrier generation efficiency, non-radiative recombination loss, and charge extraction capability, thus playing a decisive role in the device's power conversion efficiency and long-term operational stability. Therefore, the selection of material systems, defect control strategies, and optimization of film deposition processes for perovskite thin films have become key research directions for improving the performance and reliability of PSCs.

[0004] Existing perovskite thin film material systems mainly include lead-based perovskite films, lead-tin hybrid perovskite films, and tin-based perovskite films. Among them, lead-based systems have better efficiency, but they suffer from lead toxicity and potential environmental regulatory pressures; lead-tin hybrid systems can be used for multilayer devices through bandgap tuning, but the issues of component stability and ion migration are relatively complex; tin-based perovskite films have greater advantages in environmental friendliness and have the potential to be better adapted to near-infrared spectral response, thus becoming an important research direction for low-toxicity / lead-free routes and attracting much attention.

[0005] However, tin-based perovskite films also have certain defects, Sn 2+ It is easily oxidized to Sn in the presence of water and oxygen, under continuous light irradiation, or under thermal stress. 4+This oxidation process induces intrinsic defects such as tin vacancies and leads to enhanced p-type self-doping, increasing defect state density and significantly increasing non-radiative recombination, resulting in open-circuit voltage loss and rapid device performance degradation. Simultaneously, oxidation-induced defect accumulation often couples with grain boundary / surface defects, further promoting halide ion migration and side reactions, leading to decreased film density, pinhole expansion, and intensified localized degradation. Under continuous light irradiation, the aforementioned defect generation and ion migration processes are further activated and accelerated by photogenerated carriers and localized photothermal effects, causing tin-based perovskite films to exhibit insufficient radiation resistance, thus failing to meet the application requirements for long-term reliable operation of perovskite solar cells.

[0006] Therefore, there is a need to provide a method for preparing a perovskite precursor solution and a radiation-resistant perovskite thin film to solve the problems existing in the prior art. Summary of the Invention

[0007] In view of this, the present invention provides a method for preparing a perovskite precursor solution and a radiation-resistant perovskite thin film, which can reduce defects and non-radiative recombination while improving the stability of the film under irradiation conditions.

[0008] To achieve the above objectives, the present invention provides a method for preparing a perovskite precursor solution, comprising the following steps:

[0009] S1. In a nitrogen glove box, add usnic acid and α-tocopherol to anhydrous DMF, heat and stir, disperse by ultrasonication, and then add DMSO and mix well to obtain a usnic acid / α-tocopherol solution.

[0010] S2. FAI, SnI2, SnF2 and EDAI2 are added sequentially to the usnic acid / α-tocopherol solution and magnetically stirred. Then 1,4-divinylperfluorobutane and AIBN are added and stirred again. The mixture is then sonicated and filtered through a PTFE membrane to obtain the perovskite precursor solution.

[0011] This invention incorporates usnic acid and α-tocopherol into a perovskite precursor solution, wherein the structural formula of usnic acid is as follows:

[0012]

[0013] As a multifunctional defect-regulating additive component in this invention, it contains both hydroxyl and polycarbonyl groups as interaction sites, which can interact with uncoordinated Sn at perovskite grain boundaries. 2+The site coordinates with halogen-related defect sites through hydrogen bonding or electrostatic interactions, thereby reducing grain boundary defect density and weakening carrier capture at grain boundaries, reducing non-radiative recombination losses and extending carrier lifetime. At the same time, its stabilizing and passivating effect on halogen-related defects (such as halogen vacancies) helps to suppress the formation of halogen vacancies and halide ion migration, thereby reducing the risk of defect multiplication, pinhole expansion and local phase separation caused by ion migration. It also further reduces the risk of defect activation and accelerated ion migration caused by charge accumulation under irradiation, reduces the rate of irradiation-induced defect evolution, and improves the overall radiation resistance from the source.

[0014] α-Tocopherol molecules can capture free radical / reactive oxygen intermediates and terminate oxidation chain reactions, thereby inhibiting Sn to some extent. 2+ To Sn 4+ This process reduces oxidation and the resulting decomposition side reactions, improving the storage stability of the perovskite precursor solution. Furthermore, its polar sites such as phenolic hydroxyl groups and hydrophobic long-chain structure allow it to form a hydrophobic protective effect on the grain surface / grain boundary region, reducing water and oxygen adsorption and diffusion into the bulk phase, and inhibiting Sn²2 oxidation triggered by oxygen-related intermediates. + Oxidation and decomposition reactions enhance the oxygen resistance and light stability of Sn-based perovskites. Meanwhile, the reversible interaction between α-tocopherol and precursor components such as SnI2 / FAI helps regulate the complexation and nucleation / crystallization rate of precursors, thereby making crystallization smoother and more controllable, promoting uniform grain growth and film densification, reducing pinholes and surface defects and reducing defect formation and aggregation, thus providing a structural basis for subsequent radiation resistance stability.

[0015] Furthermore, this invention adds 1,4-divinylperfluorobutane to the perovskite precursor solution to further improve the density of the final perovskite film and reduce water and oxygen permeation and ion migration channels. The structural formula of 1,4-divinylperfluorobutane is as follows:

[0016]

[0017] It has low surface energy and hydrophobic properties, and is easy to accumulate in grain boundaries and surface areas to reduce water and oxygen permeation; at the same time, during the AIBN initiation and subsequent annealing process, its vinyl groups can undergo in-situ free radical polymerization to generate a certain amount of fluorinated polymers / crosslinked structures, which can block and solidify grain boundary pores and micropores, thereby reducing the probability of permeation and ion migration channel opening.

[0018] The synergistic effect of these multiple factors helps to reduce the defect evolution rate induced by charge accumulation and defect activation under irradiation conditions, improve the performance retention and stability of subsequent perovskite films in irradiated environments, and thus enhance the photoelectric conversion efficiency and stability of perovskite solar cells.

[0019] Optionally, in step S1, in a nitrogen glove box, usnic acid and α-tocopherol are added to anhydrous DMF, magnetically stirred at 50-55°C for 20-25 minutes, ultrasonically dispersed for 5-8 minutes, and then DMSO is added and mixed to obtain a usnic acid / α-tocopherol solution.

[0020] The present invention employs stirring at 50-55°C combined with short-term ultrasonic dispersion when preparing the usnic acid / α-tocopherol solution, which can effectively reduce the introduction of water and oxygen and local concentration gradients, avoid uneven film formation caused by the aggregation or incomplete dissolution of usnic acid and α-tocopherol, thereby improving the uniformity of the perovskite precursor solution.

[0021] Optionally, the 1,4-divinylperfluorobutane is prepared by adding 3-3.5 parts by mass of I2 into a reactor, purging and replacing it three times with high-purity nitrogen, adding 2.8-3.3 parts by mass of tetrafluoroethylene, heating and stirring at 120-150°C for 2-3 hours, cooling to room temperature, adding 0.015-0.02 parts by mass of CuI, purging and replacing it three more times with nitrogen, adding 1.8-2 parts by mass of ethylene, heating to 180-220°C and reacting for 5.5-6.5 hours, adding 0.9-0.95 parts by mass of KOH and 8-11 parts by volume of ethanol to the reactor, stirring and refluxing at 90°C for 20-30 minutes, cooling to room temperature, filtering, washing with deionized water until neutral, drying, and distilling under reduced pressure.

[0022] Optionally, in step S2, FAI, SnI2, SnF2, and EDAI2 are added sequentially to the usnic acid / α-tocopherol solution, and the mixture is magnetically stirred at 45-55°C for 2-3 hours. Then, 1,4-divinylperfluorobutane is added and stirring is continued for 20-30 minutes. Finally, AIBN is added and stirred for 20-30 minutes, followed by ultrasonic treatment for 5-10 minutes. The mixture is then filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

[0023] The perovskite precursor solution comprises the following raw materials in parts by weight: 140-180 parts by weight of FAI, 300-350 parts by weight of SnI2, 12-16 parts by weight of SnF2, 2.5-5 parts by weight of EDAI2, 0.08-0.13 parts by weight of 1,4-divinylperfluorobutane, 0.005-0.008 parts by weight of AIBN, 0.1-0.2 parts by weight of usnic acid, and 1.8-3.6 parts by weight of α-tocopherol, and further comprises 100-150 parts by volume of anhydrous DMF and 900-1000 parts by volume of DMSO.

[0024] The present invention also provides a radiation-resistant perovskite thin film, comprising 0.4-0.5 volume parts of arginine-PEDOT:PSS solution, 0.3-0.4 volume parts of perovskite precursor solution, and 1.2-1.6 volume parts of anhydrous chlorobenzene, and prepared by the following steps:

[0025] T1. Mix PEDOT:PSS solution and arginine, stir magnetically, and filter to obtain arginine-PEDOT:PSS solution;

[0026] T2. Arginine-PEDOT:PSS solution was dropped onto the pretreated ITO substrate, spin-coated, annealed, and cooled to obtain the hole transport layer.

[0027] T3. Further perovskite precursor solution is added dropwise to the hole transport layer and spin-coated. Anhydrous chlorobenzene is added dropwise during spin-coating. After spin-coating, the film is annealed under an inert atmosphere and cooled to room temperature to obtain a radiation-resistant perovskite film.

[0028] This invention involves doping PEDOT:PSS with arginine. The amino group of arginine forms ion pairs and hydrogen bonds with the sulfonic acid groups of PSS, reducing the effective acidity of free acidic groups in the PEDOT:PSS system. This also induces ionic crosslinking and confinement of the PSS segments, thereby weakening their hygroscopicity and reducing their migration and interfacial enrichment tendencies. Furthermore, the reduction in interfacial acidity and water / oxygen enrichment further inhibits Sn deposition at the hole transport layer and perovskite film interface. 2+ The formation and accumulation of oxidation and halogen-related defects enhance the stability of the thin film under strong light / heat / irradiation conditions, thereby improving the stability of photoelectric conversion efficiency.

[0029] Optionally, in step T1, 1000-1500 volume parts of PEDOT:PSS solution and 0.16-0.5 mass parts of arginine are mixed, magnetically stirred for 30-60 minutes, and filtered through a 0.45μm PTFE membrane to obtain an arginine-PEDOT:PSS solution.

[0030] This invention filters the arginine-PEDOT:PSS solution to remove microgels and aggregated particles generated during stirring, thereby improving the cleanliness and film uniformity of the arginine-PEDOT:PSS solution and reducing the risk of pinholes and interface defects.

[0031] Optionally, the pretreated ITO substrate is obtained by sequentially placing an ITO conductive glass substrate in deionized water, acetone, and isopropanol for ultrasonic cleaning for 10-15 minutes, drying it with nitrogen, and then subjecting it to ultraviolet ozone treatment for 20-30 minutes.

[0032] This invention can effectively remove organic contaminants from the ITO surface and improve its surface energy and wettability through pretreatment, thereby enhancing the spread and film formation of the hole transport layer and the interfacial bonding, and reducing interfacial defects.

[0033] Optionally, in step T2, the arginine-PEDOT:PSS solution is dropped onto the pretreated ITO substrate, spin-coated at 4000 rpm for 25-35 s, annealed on a heating plate at 130-140℃ for 20-30 min, and cooled to obtain the hole transport layer.

[0034] Optionally, in step T3, a perovskite precursor solution is further added to the hole transport layer and spin-coated at 1000 rpm for 8-12 seconds, followed by spin-coating at 5000 rpm for 40-50 seconds. When the second spin-coating is in progress with 10 seconds remaining, anhydrous chlorobenzene is added, and spin-coating continues until the end. After spin-coating, the film is annealed at 85°C for 10-15 minutes under a nitrogen atmosphere, then heated to 100-115°C for annealing for 5-8 minutes, and finally cooled to room temperature to obtain a radiation-resistant perovskite film.

[0035] The radiation-resistant perovskite thin film prepared by this invention has both a low-defect dense structure and interface stability, which can effectively suppress radiation-induced oxidation, ion migration and performance degradation, thereby improving the stability and performance retention rate under irradiation conditions.

[0036] The above-described technical solution of the present invention has at least the following beneficial effects:

[0037] 1. In the perovskite precursor solution of this invention, the usnic acid, relying on hydroxyl and polycarbonyl groups as interaction sites, can interact with uncoordinated Sn at grain boundaries. 2+ It coordinates with halogen-related defects through coordination / hydrogen bonding / electrostatic interactions, reduces grain boundary defects and carrier trapping, decreases nonradiative recombination, and extends lifetime; at the same time, it stabilizes and passivates halogen vacancies, inhibits ion migration, reduces pinhole expansion and local phase separation, and slows down irradiation-induced defect evolution.

[0038] 2. In this invention, α-tocopherol in the perovskite precursor solution can capture free radical / reactive oxygen intermediates and terminate the oxidation chain reaction, inhibiting Sn. 2+ Oxidation and decomposition side reactions improve the storage stability of the precursor solution; its hydrophobic long chain interacts with phenolic hydroxyl groups to form a protective layer on the grain surface / grain boundary, reducing water and oxygen adsorption and diffusion, and improving oxygen and light resistance stability; and through reversible interaction with the precursor, it regulates complexation and crystallization, making crystallization smoother, the film denser, and pinhole defects fewer.

[0039] 3. The 1,4-divinylperfluorobutane in the perovskite precursor solution of this invention has low surface energy and hydrophobic properties, and is easy to accumulate at grain boundaries / surfaces to form a barrier layer, reducing water and oxygen permeation and weakening ion migration channels; during the AIBN initiation and annealing process, its vinyl groups undergo in-situ free radical polymerization to generate fluorinated polymers / crosslinked structures, which seal and solidify grain boundary pores and micropores, reduce through channels and defect propagation, and further improve the film density and resistance to degradation. Attached Figure Description

[0040] Figure 1 This is a SEM image of the radiation-resistant perovskite thin film prepared in Example 1 of the present invention.

[0041] Figure 2 The images show the photoluminescence spectra of the radiation-resistant perovskite thin films prepared in Example 1 and Comparative Examples 1-4 of this invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. The described embodiments are some embodiments of the present invention, and all other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0043] Example 1

[0044] 3g of I2 was added to the reactor, and the mixture was purged with high-purity nitrogen three times. 2.8g of tetrafluoroethylene was added, and the mixture was heated and stirred at 120℃ for 2 hours. After cooling to room temperature, 0.015g of CuI was added, and the mixture was purged with nitrogen three times. Then, 1.8g of ethylene was added, and the mixture was heated to 180℃ and reacted for 5.5 hours. 0.9g of KOH and 8mL of ethanol were added to the reactor, and the mixture was stirred and refluxed at 90℃ for 20 minutes. After cooling to room temperature, the mixture was filtered, washed with deionized water until neutral, dried, and distilled under reduced pressure to obtain 1,4-divinylperfluorobutane.

[0045] In a nitrogen glove box, 0.1 g of usnic acid and 1.8 g of α-tocopherol were added to 100 mL of anhydrous DMF and magnetically stirred at 50 °C for 20 min, followed by ultrasonic dispersion for 5 min. 900 mL of DMSO was added and mixed well. Then, 140 g of FAI, 300 g of SnI2, 12 g of SnF2, and 2.5 g of EDAI2 were added sequentially and magnetically stirred at 45 °C for 2 h. 0.08 g of 1,4-divinylperfluorobutane was added and stirring was continued for 20 min. Finally, 0.005 g of AIBN was added and stirred for 20 min, followed by ultrasonic treatment for 5 min. The mixture was filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

[0046] Mix 1000 mL of PEDOT:PSS solution with 0.16 g of arginine, stir magnetically for 30 min, and then pass through a 0.45 μm filter. The arginine-PEDOT:PSS solution was obtained by filtration through a PTFE membrane. An ITO conductive glass substrate was then ultrasonically cleaned in deionized water, acetone, and isopropanol for 10 min, dried with nitrogen, and subjected to UV ozone treatment for 20 min. 0.4 mL of the arginine-PEDOT:PSS solution was then dropped onto the pretreated ITO substrate and spin-coated at 4000 rpm for 25 s. The substrate was then annealed on a 130℃ hot plate for 20 min to obtain an arginine-doped PEDOT:PSS hole transport layer. After cooling, 0.3 mL of perovskite precursor solution was added and spin-coated at 1000 rpm for 8 s, followed by spin-coating at 5000 rpm for 40 s. With 10 s remaining in the second spin-coating step, 1.2 mL of anhydrous chlorobenzene was added, and spin-coating continued until completion. After spin-coating, the substrate was annealed at 85℃ for 10 min under a nitrogen atmosphere, then heated to 100℃ for 5 min, and cooled to room temperature to obtain a radiation-resistant perovskite film.

[0047] Example 2

[0048] 3.1 g I2 was added to the reactor, and the mixture was purged with high-purity nitrogen three times. 2.9 g tetrafluoroethylene was added, and the mixture was heated and stirred at 125 °C for 2.2 h. After cooling to room temperature, 0.016 g CuI was added, and the mixture was purged with nitrogen three times. Then 1.85 g ethylene was added, and the mixture was heated to 190 °C and reacted for 5.7 h. 0.91 g KOH and 8.5 mL ethanol were added to the reactor, and the mixture was stirred and refluxed at 90 °C for 22 min. After cooling to room temperature, the mixture was filtered, washed with deionized water until neutral, dried, and distilled under reduced pressure to obtain 1,4-divinylperfluorobutane.

[0049] In a nitrogen glove box, 0.12 g of usnic acid and 2.2 g of α-tocopherol were added to 110 mL of anhydrous DMF and magnetically stirred at 51 °C for 20 min, followed by ultrasonic dispersion for 6 min. 920 mL of DMSO was added and mixed well. Then, 150 g of FAI, 310 g of SnI2, 13 g of SnF2, and 3 g of EDAI2 were added sequentially and magnetically stirred at 48 °C for 2.3 h. 0.09 g of 1,4-divinylperfluorobutane was added and stirring was continued for 22 min. Finally, 0.0055 g of AIBN was added and stirred for 22 min, followed by ultrasonic treatment for 6 min. The mixture was filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

[0050] Mix 1100 mL of PEDOT:PSS solution with 0.2 g of arginine, stir magnetically for 40 min, and then pass through a 0.45 μm filter. The arginine-PEDOT:PSS solution was obtained by filtration through a PTFE membrane. An ITO conductive glass substrate was then ultrasonically cleaned in deionized water, acetone, and isopropanol for 12 min, dried with nitrogen, and subjected to UV ozone treatment for 22 min. 0.42 mL of the arginine-PEDOT:PSS solution was then dropped onto the pretreated ITO substrate and spin-coated at 4000 rpm for 28 s. The substrate was then annealed on a 132℃ hot plate for 22 min to obtain an arginine-doped PEDOT:PSS hole transport layer. After cooling, 0.32 mL of perovskite precursor solution was added and spin-coated at 1000 rpm for 9 s, followed by spin-coating at 5000 rpm for 42 s. With 10 s remaining in the second spin-coating step, 1.30 mL of anhydrous chlorobenzene was added, and spin-coating continued until completion. After spin-coating, the substrate was annealed at 85℃ for 11 min under a nitrogen atmosphere, then heated to 105℃ for 6 min, and cooled to room temperature to obtain a radiation-resistant perovskite film.

[0051] Example 3

[0052] 3.5 g I2 was added to the reactor, and the mixture was purged with high-purity nitrogen three times. 3.3 g tetrafluoroethylene was added, and the mixture was heated and stirred at 150 °C for 3 h. After cooling to room temperature, 0.02 g CuI was added, and the mixture was purged with nitrogen three times. 2 g ethylene was then added, and the mixture was heated to 220 °C and reacted for 6.5 h. 0.95 g KOH and 11 mL ethanol were added to the reactor, and the mixture was stirred and refluxed at 90 °C for 30 min. After cooling to room temperature, the mixture was filtered, washed with deionized water until neutral, dried, and distilled under reduced pressure to obtain 1,4-divinylperfluorobutane.

[0053] In a nitrogen glove box, 0.2 g of usnic acid and 3.6 g of α-tocopherol were added to 150 mL of anhydrous DMF and magnetically stirred at 55 °C for 20 min, followed by ultrasonic dispersion for 8 min. 1000 mL of DMSO was added and mixed well. Then, 180 g of FAI, 350 g of SnI2, 16 g of SnF2, and 5 g of EDAI2 were added sequentially and magnetically stirred at 55 °C for 3 h. 0.13 g of 1,4-divinylperfluorobutane was added and stirring was continued for 30 min. Finally, 0.008 g of AIBN was added and stirred for 30 min, followed by ultrasonic treatment for 10 min. The mixture was then filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

[0054] Mix 1500 mL of PEDOT:PSS solution with 0.5 g of arginine, stir magnetically for 60 min, and then pass through a 0.45 μm filter. The arginine-PEDOT:PSS solution was obtained by filtration through a PTFE membrane. An ITO conductive glass substrate was sequentially ultrasonically cleaned in deionized water, acetone, and isopropanol for 15 min, dried with nitrogen, and subjected to UV ozone treatment for 30 min. Then, 0.5 mL of the arginine-PEDOT:PSS solution was dropped onto the pretreated ITO substrate and spin-coated at 4000 rpm for 35 s. The substrate was then annealed on a 140℃ hot plate for 30 min to obtain an arginine-doped PEDOT:PSS hole transport layer. After cooling, 0.4 mL of perovskite precursor solution was added and spin-coated at 1000 rpm for 12 s, followed by spin-coating at 5000 rpm for 50 s. With 10 s remaining in the second spin-coating step, 1.6 mL of anhydrous chlorobenzene was added, and spin-coating continued until completion. After spin-coating, the substrate was annealed at 85℃ for 15 min under a nitrogen atmosphere, then heated to 115℃ for 8 min, and cooled to room temperature to obtain a radiation-resistant perovskite film.

[0055] Example 4

[0056] 3.3 g I2 was added to a reactor, and the mixture was purged with high-purity nitrogen three times. 3.1 g tetrafluoroethylene was added, and the mixture was heated and stirred at 140 °C for 2.8 h. After cooling to room temperature, 0.018 g CuI was added, and the mixture was purged with nitrogen three times. Then 1.95 g ethylene was added, and the mixture was heated to 210 °C and reacted for 6.2 h. 0.93 g KOH and 9.5 mL ethanol were added to the reactor, and the mixture was stirred and refluxed at 90 °C for 27 min. After cooling to room temperature, the mixture was filtered, washed with deionized water until neutral, dried, and distilled under reduced pressure to obtain 1,4-divinylperfluorobutane.

[0057] In a nitrogen glove box, 0.16 g of usnic acid and 2.8 g of α-tocopherol were added to 130 mL of anhydrous DMF and magnetically stirred at 53 °C for 20 min, followed by ultrasonic dispersion for 7 min. 970 mL of DMSO was added and mixed well. Then, 165 g of FAI, 330 g of SnI2, 14.5 g of SnF2, and 4 g of EDAI2 were added sequentially and magnetically stirred at 52 °C for 2.7 h. 0.11 g of 1,4-divinylperfluorobutane was added and stirring was continued for 27 min. Finally, 0.006 g of AIBN was added and stirred for 27 min, followed by ultrasonic treatment for 8 min. The mixture was filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

[0058] Mix 1300 mL of PEDOT:PSS solution with 0.36 g of arginine, stir magnetically for 50 min, and then pass through a 0.45 μm filter. The arginine-PEDOT:PSS solution was obtained by filtration through a PTFE membrane. An ITO conductive glass substrate was sequentially ultrasonically cleaned in deionized water, acetone, and isopropanol for 13 min, dried with nitrogen, and subjected to UV ozone treatment for 27 min. Then, 0.47 mL of the arginine-PEDOT:PSS solution was dropped onto the pretreated ITO substrate and spin-coated at 4000 rpm for 32 s. The substrate was then annealed on a 138℃ hot plate for 28 min to obtain an arginine-doped PEDOT:PSS hole transport layer. After cooling, 0.37 mL of perovskite precursor solution was further added and spin-coated at 1000 rpm for 11 s, followed by spin-coating at 5000 rpm for 47 s. With 10 s remaining in the second spin-coating step, 1.5 mL of anhydrous chlorobenzene was added, and spin-coating continued until completion. After spin-coating, the substrate was annealed at 85℃ for 13 min under a nitrogen atmosphere, then heated to 112℃ for 7 min, and cooled to room temperature to obtain a radiation-resistant perovskite film.

[0059] Example 5

[0060] 3.4 g of I2 was added to a reaction vessel, and the mixture was purged with high-purity nitrogen three times. Then, 3.2 g of tetrafluoroethylene was added. The mixture was heated and stirred at 145 °C for 3 h, then cooled to room temperature. 0.019 g of CuI was added, and the mixture was purged with nitrogen three times. Then, 1.98 g of ethylene was added, and the mixture was heated to 215 °C and reacted for 6.4 h. 0.94 g of KOH and 10.5 mL of ethanol were added to the reactor, and the mixture was stirred and refluxed at 90 °C for 29 min. The mixture was then cooled to room temperature, filtered, washed with deionized water until neutral, dried, and distilled under reduced pressure to obtain 1,4-divinylperfluorobutane.

[0061] In a nitrogen glove box, 0.18 g of usnic acid and 3.2 g of α-tocopherol were added to 140 mL of anhydrous DMF and magnetically stirred at 54 °C for 20 min, followed by ultrasonic dispersion for 7.5 min. 990 mL of DMSO was added and mixed well. Then, 175 g of FAI, 340 g of SnI2, 15.5 g of SnF2, and 4.5 g of EDAI2 were added sequentially and magnetically stirred at 54 °C for 2.9 h. 0.12 g of 1,4-divinylperfluorobutane was added and stirring was continued for 29 min. Finally, 0.0072 g of AIBN was added and stirred for 29 min. The mixture was then ultrasonicated for 9 min and filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

[0062] 1400 mL of PEDOT:PSS solution and 0.42 g of arginine were mixed and magnetically stirred for 55 min. The mixture was then filtered through a 0.45 μm PTFE membrane to obtain an arginine-PEDOT:PSS solution. An ITO conductive glass substrate was ultrasonically cleaned in deionized water, acetone, and isopropanol for 14 min, dried with nitrogen, and subjected to UV ozone treatment for 28 min. 0.49 mL of the arginine-PEDOT:PSS solution was then dropped onto the pretreated ITO substrate and spin-coated at 4000 rpm for 34 s. The substrate was then annealed on a 140 °C hot plate for 30 min to obtain arginine-doped PEDOT:PSS. EDOT: PSS hole transport layer. After cooling, 0.39 mL of perovskite precursor solution was added dropwise and spin-coated at 1000 rpm for 12 s, followed by spin-coating at 5000 rpm for 49 s. When there were 10 s left in the second spin-coating step, 1.55 mL of anhydrous chlorobenzene was added dropwise, and spin-coating continued until the end. After spin-coating, the film was annealed at 85 °C for 14 min under a nitrogen atmosphere, then heated to 114 °C for annealing for 7.5 min, and cooled to room temperature to obtain a radiation-resistant perovskite film.

[0063] Example 6

[0064] 3.2 g I2 was added to a reaction vessel, and the mixture was purged with high-purity nitrogen three times. 3 g tetrafluoroethylene was added, and the mixture was heated and stirred at 130 °C for 2.5 h. After cooling to room temperature, 0.017 g CuI was added, and the mixture was purged with nitrogen three times. 1.9 g ethylene was then added, and the mixture was heated to 200 °C and reacted for 6 h. 0.92 g KOH and 9 mL ethanol were added to the reactor, and the mixture was stirred and refluxed at 90 °C for 25 min. After cooling to room temperature, the mixture was filtered, washed with deionized water until neutral, dried, and distilled under reduced pressure to obtain 1,4-divinylperfluorobutane.

[0065] In a nitrogen glove box, 0.14 g of usnic acid and 2.4 g of α-tocopherol were added to 120 mL of anhydrous DMF and magnetically stirred at 52 °C for 20 min, followed by ultrasonic dispersion for 6.5 min. 950 mL of DMSO was added and mixed well. Then, 160 g of FAI, 320 g of SnI2, 14 g of SnF2, and 3.5 g of EDAI2 were added sequentially and magnetically stirred at 50 °C for 2.5 h. 0.1 g of 1,4-divinylperfluorobutane was added and stirring was continued for 25 min. Finally, 0.006 g of AIBN was added and stirred for 25 min, followed by ultrasonic treatment for 7 min. The mixture was then filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

[0066] 1200 mL of PEDOT:PSS solution and 0.28 g of arginine were mixed and magnetically stirred for 45 min. The mixture was then filtered through a 0.45 μm PTFE membrane to obtain the arginine-PEDOT:PSS solution. An ITO conductive glass substrate was sequentially ultrasonically cleaned in deionized water, acetone, and isopropanol for 12 min, dried with nitrogen, and subjected to UV ozone treatment for 25 min. Then, 0.45 mL of the arginine-PEDOT:PSS solution was dropped onto the pretreated ITO substrate and spin-coated at 4000 rpm for 30 s. The substrate was then annealed on a 135 °C hot plate for 25 min to obtain arginine-doped PEDOT:PSS. EDOT: PSS hole transport layer. After cooling, 0.35 mL of perovskite precursor solution was added dropwise and spin-coated at 1000 rpm for 10 s, followed by spin-coating at 5000 rpm for 45 s. When there were 10 s left in the second spin-coating step, 1.40 mL of anhydrous chlorobenzene was added dropwise, and spin-coating continued until the end. After spin-coating, the film was annealed at 85 °C for 12 min under a nitrogen atmosphere, then heated to 110 °C for annealing for 6.5 min, and cooled to room temperature to obtain a radiation-resistant perovskite film.

[0067] The present invention also includes comparative examples and related experiments.

[0068] Comparative Example 1

[0069] Compared with Example 3, the only difference is that no isocrine acid was added, but the other preparation methods and components are completely the same, and the radiation-resistant perovskite film is finally obtained.

[0070] Comparative Example 2

[0071] Compared with Example 3, the only difference is that α-tocopherol was not added, but the other preparation methods and components were completely consistent, and the radiation-resistant perovskite film was finally obtained.

[0072] Comparative Example 3

[0073] Compared with Example 3, the only difference is that 1,4-divinylperfluorobutane was not added. The other preparation methods and components are completely consistent, and the radiation-resistant perovskite film is finally obtained.

[0074] Comparative Example 4

[0075] Compared with Example 3, the only difference is that arginine was not added, but the other preparation methods and components are completely the same, and the radiation-resistant perovskite film is finally obtained.

[0076] Performance testing

[0077] The performance of the radiation-resistant perovskite films prepared in Examples 1-6 and Comparative Examples 1-4 was tested and analyzed. The specific test and analysis are as follows:

[0078] (1) The morphology of the thin film was analyzed using a field emission scanning electron microscope (model JSM-7610F). The scanning electron microscope image of the radiation-resistant perovskite thin film prepared in Example 1 is shown in the figure. Figure 1 ;

[0079] (2) The charge recombination performance and carrier lifetime of the radiation-resistant perovskite solar cell films prepared in Examples 1-6 and Comparative Examples 1-4 were evaluated using photoluminescence characteristics. Measurements were performed using a Hitachi F-4600 spectrophotometer equipped with a 485nm laser excitation source (average power 0.25mW). The photoluminescence spectra of Examples 1 and Comparative Examples 1-4 are shown below. Figure 2 And record the initial photoluminescence peak intensity (PL0) of each sample.

[0080] (3) The radiation-resistant perovskite solar cell thin films prepared in Examples 1-6 and Comparative Examples 1-4 were subjected to ultraviolet radiation stability tests in accordance with the national standard GB / T19394-2003 "Photovoltaic (PV) Module Ultraviolet Test" and damp heat stability tests in accordance with GB / T2423.3-2016 "Environmental Testing Part 2: Test Methods Test Cab: Constant Damp Heat Test". The peak photoluminescence intensity (PL1) after irradiation and the peak photoluminescence intensity (PL2) after damp heat were measured and recorded by Hitachi F-4600 spectrophotometer for the samples after ultraviolet radiation stability test and damp heat stability test. The luminescence intensity retention rate (%) was calculated by the following formula (Ⅰ) to evaluate the radiation resistance and damp heat resistance.

[0081] Luminous intensity retention rate = (PL1 / PL0) × 100% (or (PL2 / PL0) × 100%) (Ⅰ)

[0082] In addition, the surface hydrophobicity performance was tested in accordance with the national standard GB / T30447-2013 "Method for Measurement of Contact Angle of Nanofilms"; the specific test results are shown in Table 1.

[0083] (4) The battery samples prepared using the radiation-resistant perovskite thin films of Examples 1-6 and Comparative Examples 1-4 were tested using an AM1.5G standard solar simulator (light intensity 100mW / cm²). 2 The current-voltage (JV) characteristics were tested using a PT-SUN2S instrument and a Keithley 2400 test source meter, with the illumination area set to 0.051 cm² using a mask. 2 During testing, the scan range was -0.2V to 1.2V, and the scan rate was 0.025V / s. The specific open-circuit voltage (V...) oc (V), short-circuit current density (J) sc mA / cm 2The test results for fill factor (FF, %) and photoelectric conversion efficiency (PCE, %) are shown in Table 2.

[0084] Table 1

[0085]

[0086] First, from Figure 1 As shown in Example 1, the radiation-resistant perovskite film has a relatively smooth surface, large and uniformly distributed grain size, and no obvious pinholes or through cracks. This indicates that the embodiments of the present invention can promote dense film formation and reduce the probability of grain boundary defect enrichment. Combined with the analysis of Table 1 and... Figure 2 The test results further show that the radiation-resistant perovskite films prepared in Examples 1-6 of this invention have good luminescence intensity and exhibit high luminescence intensity retention rates after both ultraviolet irradiation and damp heat aging, which are significantly better than those of Comparative Examples 1-4. Specifically, the luminescence intensity retention rates after irradiation in Examples 1-6 are 84%-93%, and after damp heat aging, they are 80%-92%, with contact angles of 92°-103°, indicating that the films possess low non-radiative recombination loss, relatively stable defect states, and good surface hydrophobic barrier properties.

[0087] In contrast, the absence of usnic acid or α-tocopherol in Comparative Examples 1 and 2 significantly reduced the luminescence intensity retention rate of the samples after UV irradiation and damp heat stability tests, respectively. This indicates that the introduction of usnic acid and α-tocopherol reduced the defect and non-radiative recombination of the radiation-resistant perovskite film under irradiation / damp heat conditions, thereby improving the luminescence intensity retention rate. Comparative Example 3, lacking 1,4-divinylperfluorobutane, had a contact angle of only 62°, significantly lower than Examples 1-6, and its luminescence intensity retention rate decreased significantly after damp heat. Furthermore, the absence of arginine in Comparative Example 4 also resulted in a significant decrease in luminescence intensity retention rate after irradiation and damp heat, indicating that the introduction of arginine into the PEDOT:PSS system also plays a positive role in resisting radiation perovskite films.

[0088] Table 2

[0089]

[0090] As shown in Table 2, the battery samples prepared using the radiation-resistant perovskite thin films of Examples 1-6 exhibit superior J-V output parameters and higher photoelectric conversion efficiency, significantly outperforming Comparative Examples 1-4. Comparative Examples 1 and 2, lacking either usnic acid or α-tocopherol, resulted in a significant decrease in Voc and FF; Comparative Example 3, lacking 1,4-divinylperfluorobutane, showed a significant decrease in FF; and Comparative Example 4, lacking arginine, also resulted in a decrease in Voc and FF. In summary, the results in Table 2 further demonstrate that the technical solution of this invention can significantly reduce device voltage and fill factor loss while improving thin film stability, thereby improving the photoelectric conversion efficiency and performance retention of the prepared battery samples.

[0091] The above are preferred embodiments of the present invention. Those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a perovskite precursor solution, characterized by, Includes the following steps: S1. In a nitrogen glove box, add usnic acid and α-tocopherol to anhydrous DMF, heat and stir, disperse by ultrasonication, and then add DMSO and mix well to obtain a usnic acid / α-tocopherol solution. S2. FAI, SnI2, SnF2 and EDAI2 are added sequentially to the usnic acid / α-tocopherol solution and magnetically stirred. Then 1,4-divinylperfluorobutane and AIBN are added and stirred again. The mixture is then sonicated and filtered through a PTFE membrane to obtain the perovskite precursor solution.

2. The method for preparing a perovskite precursor solution according to claim 1, characterized in that, In step S1, in a nitrogen glove box, usnic acid and α-tocopherol are added to anhydrous DMF, and after magnetic stirring at 50-55°C for 20-25 minutes, ultrasonic dispersion is carried out for 5-8 minutes. Then, DMSO is added and mixed to obtain a usnic acid / α-tocopherol solution.

3. The method of claim 1, wherein the perovskite precursor solution is prepared by adding a halide salt and a metal salt to a solvent. The 1,4-divinylperfluorobutane was prepared by adding 3-3.5 parts by mass of I2 into a reactor, purging and replacing it three times with high-purity nitrogen, adding 2.8-3.3 parts by mass of tetrafluoroethylene, heating and stirring at 120-150°C for 2-3 hours, cooling to room temperature, adding 0.015-0.02 parts by mass of CuI, purging and replacing it three more times with nitrogen, adding 1.8-2 parts by mass of ethylene, heating to 180-220°C and reacting for 5.5-6.5 hours, adding 0.9-0.95 parts by mass of KOH and 8-11 parts by volume of ethanol to the reactor, stirring and refluxing at 90°C for 20-30 minutes, cooling to room temperature, filtering, washing with deionized water until neutral, drying, and distilling under reduced pressure.

4. The method of claim 1, wherein the perovskite precursor solution is prepared by adding a halide salt and a metal salt to a solvent. In step S2, FAI, SnI2, SnF2, and EDAI2 are added sequentially to the usnic acid / α-tocopherol solution, and the mixture is magnetically stirred at 45-55°C for 2-3 hours. Then, 1,4-divinylperfluorobutane is added and stirring is continued for 20-30 minutes. Finally, AIBN is added and stirred for 20-30 minutes. The mixture is then sonicated for 5-10 minutes and filtered through a 0.22 μm PTFE membrane to obtain the perovskite precursor solution.

5. The method of claim 1, wherein the perovskite precursor solution is prepared by adding a halide salt and a metal salt to a solvent. The perovskite precursor solution comprises the following raw materials in parts by weight: 140-180 parts by weight of FAI, 300-350 parts by weight of SnI2, 12-16 parts by weight of SnF2, 2.5-5 parts by weight of EDAI2, 0.08-0.13 parts by weight of 1,4-divinylperfluorobutane, 0.005-0.008 parts by weight of AIBN, 0.1-0.2 parts by weight of usnic acid, and 1.8-3.6 parts by weight of α-tocopherol, and further comprises 100-150 parts by volume of anhydrous DMF and 900-1000 parts by volume of DMSO.

6. A radiation-resistant perovskite thin film, characterized in that, The sample was prepared by comprising 0.4–0.5 volume parts of arginine-PEDOT:PSS solution, 0.3–0.4 volume parts of perovskite precursor solution, and 1.2–1.6 volume parts of anhydrous chlorobenzene, and using the following steps: T1. Mix PEDOT:PSS solution and arginine, stir magnetically, and filter to obtain arginine-PEDOT:PSS solution; T2. Arginine-PEDOT:PSS solution was dropped onto the pretreated ITO substrate, spin-coated, annealed, and cooled to obtain the hole transport layer. T3. Further drop a perovskite precursor solution onto the hole transport layer and spin-coat it. Add anhydrous chlorobenzene during spin-coating. After spin-coating, anneal the film under an inert atmosphere and cool it to room temperature to obtain a radiation-resistant perovskite film. The perovskite precursor solution is prepared by the method for preparing a perovskite precursor solution according to any one of claims 1 to 5.

7. The radiation tolerant perovskite film of claim 6, wherein, In step T1, 1000-1500 volume parts of PEDOT:PSS solution and 0.16-0.5 mass parts of arginine are mixed, magnetically stirred for 30-60 minutes, and filtered through a 0.45μm PTFE membrane to obtain arginine-PEDOT:PSS solution.

8. The radiation tolerant perovskite film of claim 6, wherein, The pretreated ITO substrate is obtained by sequentially placing an ITO conductive glass substrate in deionized water, acetone, and isopropanol for ultrasonic cleaning for 10-15 minutes, drying it with nitrogen, and then subjecting it to ultraviolet ozone treatment for 20-30 minutes.

9. The radiation tolerant perovskite film of claim 6, wherein, In step T2, the arginine-PEDOT:PSS solution is dropped onto the pretreated ITO substrate, spin-coated at 4000 rpm for 25-35 s, annealed on a heating plate at 130-140℃ for 20-30 min, and cooled to obtain the hole transport layer.

10. The radiation tolerant perovskite film of claim 6, wherein, In step T3, a perovskite precursor solution is further added to the hole transport layer and spin-coated at 1000 rpm for 8-12 seconds, followed by spin-coating at 5000 rpm for 40-50 seconds. When there are 10 seconds left in the second spin-coating, anhydrous chlorobenzene is added, and spin-coating continues until the end. After spin-coating, the film is annealed at 85°C for 10-15 minutes under a nitrogen atmosphere, then heated to 100-115°C for annealing for 5-8 minutes, and finally cooled to room temperature to obtain a radiation-resistant perovskite film.

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