A method for improving the quality of perovskite thin film by dual application of 5-fluoro-2-aminothiazole

Abstract

This invention discloses a method for improving the quality of perovskite thin films through the dual application of 5-fluoro-2-aminothiazole, particularly suitable for perovskite solar cells in space environments. This method utilizes NiO... X A 5-fluoro-2-aminothiazole / IPA solution is spin-coated onto the surface and then doped with the perovskite phase to achieve synergistic passivation of the upper and lower interfaces. This invention significantly improves the structural stability and photoelectric performance retention of perovskite thin films in extreme space environments, such as high-energy particle radiation, wide-temperature thermal cycling, and ultraviolet irradiation, meeting the requirements of long lifespan and high reliability for space photovoltaic devices.

Description

Technical Field

[0001] This invention relates to the field of quality improvement of perovskite thin films in space, specifically a method for improving the quality of perovskite thin films through the dual application of 5-fluoro-2-aminothiazole. Background Technology

[0002] Perovskite materials, as light-absorbing layers, possess advantages such as high absorption coefficient, low exciton binding energy, and long carrier lifetime, and are widely used in the light-absorbing layers of perovskite solar cells. Compared to other thin-film solar cells, perovskite solar cells have the greatest potential to replace traditional silicon cells. Currently, the photoelectric conversion efficiency of perovskite solar cells has exceeded 26.9%, but there is still a certain gap compared to its theoretical efficiency of 33%. Related research shows that due to the ionic properties of perovskite materials, solution-prepared perovskite films have a large number of defect sites on the upper and lower surfaces of the bulk material. The generation of defect sites affects the effective conduction of charge carriers, thereby affecting the film quality and cell performance. In light of this, as described in M. Vasilopoulou, A. Fakharuddin, AGCoutsolelos, et al. Molecular materials as interfacial layers and additives in perovskite solar cells [J]. Chemical Society Reviews, 2020, 49(13): 4496-4526, perovskite doping strategies are one of the effective means to optimize thin film performance and battery performance. However, in space applications, perovskite thin films face multiple harsh environmental challenges such as extreme temperature fluctuations, high-energy particle radiation, ultraviolet irradiation, and high vacuum, which can easily lead to material degradation, increased defects, and performance decline. Currently, improving the interface quality and bulk stability of perovskite thin films, especially for design in space environments, has become a research focus in this field. Interface passivation and bulk doping are effective means to improve the environmental tolerance of perovskite, but further development of integrated methods that can simultaneously ensure high efficiency and high stability is still needed. Summary of the Invention

[0003] The purpose of this invention is to provide a method for improving the quality of perovskite thin films through the dual application of 5-fluoro-2-aminothiazole. By applying 5-fluoro-2-aminothiazole, the passivation of defects at the upper and lower interfaces and the improvement of bulk stability are achieved simultaneously, which significantly enhances the durability of perovskite in space environments such as radiation and thermal cycling.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for improving the quality of perovskite thin films through the dual application of 5-fluoro-2-aminothiazole, the specific steps of which are as follows: Weigh an appropriate amount of 5-fluoro-2-aminothiazole and use DMF as a solvent to obtain a 5-fluoro-2-aminothiazole / IPA solution with a concentration of 0.1–0.5 mg / ml. Then spin-coat the 5-fluoro-2-aminothiazole / IPA solution onto the surface of a NiOx thin film substrate to obtain a NiOx / 5-fluoro-2-aminothiazole (IPA) substrate. Weigh appropriate amounts of PbI2, PbBr2, CsI, and FAI to prepare a perovskite precursor solution, wherein the perovskite precursor solution is FAI. 1-x CsxPbIyBr 3-y (0≤x≤1, 0≤y≤3), after stirring at 60℃ for 2 hours, the solution was cooled to room temperature to obtain a perovskite precursor solution; Take an appropriate amount of 5-fluoro-2-aminothiazole and add it to the prepared perovskite precursor solution at a concentration of 3.0 mg / ml. Heat at 60-80℃ for 10-15 minutes and let it cool to room temperature for later use. A high-quality perovskite thin film is obtained by depositing a doped perovskite precursor solution onto a NiOx / 5-fluoro-2-aminothiazole (IPA) substrate using one of the following methods: spin coating, thermal evaporation, slot coating, or inkjet printing. The film is then annealed at 100°C–150°C for 10–15 minutes. The perovskite thin film material has an ABX3 structure, where the A-site is one or both of formidium and cesium ions, the B-site is lead ion, and the X-site is one of chloride, bromide, or iodide ions, or a mixture of multiple ABX3 ions under different ion conditions.

[0005] Preferably, the method further includes the following steps: depositing a gradient SiO2 protective layer on the surface of the annealed perovskite film using plasma-enhanced chemical vapor deposition (PECVD); the gradient SiO2 protective layer includes: a dense barrier layer adjacent to the perovskite film, with a thickness of 20-30 nm, used to block water vapor and particle erosion; and a stress buffer layer above the dense barrier layer, with a thickness of 60-90 nm and a porosity controlled at 5%-15%, used to release thermal cycling stress; wherein the deposition temperature is controlled at 80-100℃, the deposition time is 15-25 min, and the total thickness is 80-120 nm; the surface of the perovskite film is subjected to Ar before deposition. + Plasma pre-cleaning, with a power of 20-40W, a bias voltage of -30 to -60V, and a time of 3-5 minutes, is used to remove surface adsorbates and increase surface roughness. During deposition, a planetary rotating fixture or auxiliary heating on the back of the substrate is used to ensure that the substrate temperature uniformity is controlled within ±3℃ and the film thickness non-uniformity is <5%. The SiO2 protective layer is used to block external moisture and particle erosion, prevent carboxyl functional groups from reacting with external substances, and ensure long-term passivation.

[0006] Preferably, before depositing the gradient SiO2 protective layer, an ultraviolet light-assisted passivation step is included: the annealed perovskite film is placed in a sealed microenvironment chamber, which is filled with dry nitrogen and maintained at a positive pressure of 0.05-0.15 MPa, relative humidity ≤30%, and temperature of 25-30℃; the surface of the perovskite film is irradiated with a pulsed ultraviolet LED array with a wavelength of 365 nm, a pulse duty cycle of 40%-60%, a frequency of 0.5-2 kHz, an irradiation power density of 50-80 mW / cm², and an irradiation time of 20-30 min; during the irradiation process, a quartz light homogenizer is used to ensure that the irradiation uniformity deviation is <±5%, and the surface temperature of the perovskite film is controlled not to exceed 35℃ by a water-cooled base; ultraviolet light irradiation is used to promote the coordination binding efficiency of the carboxyl functional group of 5-fluoro-2-aminothiazole with the perovskite defect sites, and at the same time activate the synergistic enhancement effect of fluorine atoms and thiazole rings.

[0007] As a preferred embodiment, the SiO2 protective layer is doped with 0.5 wt% of an aminosilane coupling agent. The amino group of the aminosilane coupling agent can form hydrogen bonds with the carboxyl group of 5-fluoro-2-aminothiazole, which further enhances the bonding force between the SiO2 protective layer and the perovskite film. At the same time, it helps the carboxyl functional group to be fixed at the defect site, avoiding the breakage of the coordination bond.

[0008] Compared with the prior art, the beneficial effects of the present invention are: 1. A 5-fluoro-2-aminothiazole IPA solution is spin-coated onto a NiOx surface. Subsequently, a 5-fluoro-2-aminothiazole-doped perovskite precursor solution is deposited on the NiOx / 5-fluoro-2-aminothiazole (IPA) film surface. By binding the carboxyl functional groups in 5-fluoro-2-aminothiazole to the defect sites, the defect states on both the upper and lower surfaces of the perovskite film are reduced. Unlike traditional films that only have an upper surface, this method achieves both surfaces, thereby optimizing the performance of the perovskite film. 2. This invention effectively reduces the defect states on the upper and lower surfaces of the perovskite film, significantly enhancing the quality of the perovskite film; 3. The oxygen atom in the carboxyl group (-COOH) of 3-fluoro-2-aminothiazole has a lone pair of electrons, which can react with Pb on the upper and lower surfaces of the perovskite film and in the bulk phase. 2+ The empty orbitals at the defect sites form O-Pb coordination bonds (monodentate or dipentate coordination), effectively eliminating Pb. 2+ Dangling bonds, grain boundary defects, and interface state defects reduce the defect state density of perovskite; at the same time, carboxyl functional groups can form hydrogen bonds with hydroxyl groups at the NiOx interface, enhancing the bonding force between the interface passivation layer and NiOx. A hydrogen bond / covalent bond hybrid connection network is constructed between the SiO+ protective layer and the perovskite interface through an aminosilane coupling agent to avoid interface delamination. 4. The strong electronegativity of fluorine atoms can increase the polarity of 5-fluoro-2-aminothiazole molecules, enhance their interaction with perovskite, and at the same time, the steric hindrance effect of fluorine atoms can inhibit the abnormal growth of perovskite grains, improve the uniformity of grain size distribution, reduce grain boundary density, and the conjugated structure of the thiazole ring can improve the chemical stability of the molecule, avoid molecular degradation in the extreme environment of space, and ensure the long-term effectiveness of passivation.

[0009] 5. Through the synergistic encapsulation of a gradient SiO2 protective layer and an interface coupling layer, the perovskite thin film exhibits excellent resistance to thermal shock, vibration, and atomic oxygen: After MIL-STD-1540E random vibration testing (frequency range 20-2000 Hz, root mean square acceleration 14.1g, 5 min per axial direction), the film showed no peeling or cracking; after rapid thermal shock testing (-150℃↔+120℃, temperature change rate >50℃ / min, 100 cycles), the film showed no cracking (acoustic microscopy showed no debonding); after ground-based simulated atomic oxygen exposure (flux >10... 21 The mass loss of the SiO2 protective layer is <0.1 mg / cm² (equivalent to 3 years in low Earth orbit), and the photoelectric performance degradation of the perovskite film is <5%. The synergistic effect of the ultraviolet-assisted passivation and gradient encapsulation structure enables the perovskite film to maintain a vacuum level ≤10... -5 Under the combined space environment of Pa, temperature difference ±100℃, ultraviolet irradiation and proton irradiation, the photoelectric conversion efficiency is maintained at >94%, meeting the requirements of spacecraft power systems for long life and high reliability. Attached Figure Description

[0010] Figure 1 SEM images of the lower surface grains of perovskite films treated with and untreated with 5-fluoro-2-aminothiazole (IPA).

[0011] Figure 2 UV absorption spectra of perovskite films treated with and untreated with 5-fluoro-2-aminothiazole (IPA).

[0012] Figure 3 SEM images of cross-sectional grains of perovskite films doped with and undoped with 5-fluoro-2-aminothiazole.

[0013] Figure 4 XRD patterns of 5-fluoro-2-aminothiazole-doped and untreated perovskite films.

[0014] Figure 5 XPS images of 5-fluoro-2-aminothiazole-doped and untreated perovskite films.

[0015] Figure 6 PL images of 5-fluoro-2-aminothiazole-doped and untreated perovskite films.

[0016] Figure 7 PL images of perovskite thin films after CBL doping, CBL(DMF) surface treatment, and combined treatment of the upper and lower surfaces.

[0017] Figure 8 The curve showing the retention rate of photoelectric conversion efficiency (PCE) of perovskite solar cells as a function of the number of thermal cycles; Figure 9 Two-dimensional line graph comparing the PL strength retention rate of perovskite thin films under ultraviolet irradiation; Figure 10 A comprehensive comparison of the performance and stability of perovskite solar cells under proton irradiation; Figure 11 Comparison of the performance and structural stability of perovskite thin films after high vacuum exposure. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see Figures 1 to 11 This invention provides a technical solution for improving the quality of perovskite thin films through the dual application of 5-fluoro-2-aminothiazole: in: Figure 8 Conditions: -80℃ (30 minutes) ↔ +80℃ (30 minutes) constitutes one cycle, for a total of 200 cycles.

[0020] Standard: Refer to ESA-ECSS-Q-70-04A Thermal Cycling Test Specification.

[0021] Results: The film showed no cracks or peeling, and the intensity of the XRD characteristic peaks decreased by less than 3%.

[0022] Figure 9 Conditions: AM0 spectrum, ultraviolet band (280-400 nm) irradiation intensity 1.5 SUN, duration 100 hours.

[0023] Results: The UV-Vis absorption rate of the thin film was maintained at >97%, and the PL intensity decay was <5%.

[0024] Figure 10 Conditions: Energy 100 keV, Flux 1×10 11 p / cm².

[0025] Results: The photoelectric conversion efficiency (PCE) of the thin film was maintained at >94% after irradiation, and the dark current did not increase significantly.

[0026] Figure 11 Conditions: Vacuum degree ≤ 10⁻ 5 Pa, temperature 25℃, for 30 days.

[0027] Results: The film color and crystallinity showed no significant changes, and no volatiles were precipitated on the surface. Example 1

[0028] S1: Use deionized water, acetone, ethanol and isopropanol to ultrasonically clean ITO sequentially, with each ultrasonic cleaning time being 10 minutes. Then, treat the dried ITO with a plasma device for 6 minutes and take it out for later use. Spin-coat NiOx solution onto the ITO surface at 600 rpm for 30 seconds. Then, heat the NiOx-covered ITO at 100°C for 10 minutes and then let it cool to room temperature for later use.

[0029] S2: Weigh PbI2 (426.4 mg), CsI (52 mg), PbBr2 (27.5 mg) and FAI (137.6 mg), use a DMF and DMSO mixed solution with a volume ratio of 3:1 as solvent, heat at 60°C for 2 hours and then let it cool to room temperature to prepare a perovskite precursor solution, which is FA0.2Cs0.8Pb(I0.95Br0.05)3.

[0030] S3: Using IPA as a solvent, prepare a 0.3 mg / ml 5-fluoro-2-aminothiazole / IPA solution. Take 50 μL of the 0.3 mg / ml 5-fluoro-2-aminothiazole / IPA solution and spin-coat it onto the surface of the NiOx film to obtain the NiOx / CBL(DMF) substrate for later use.

[0031] S4: Take 70 μL of perovskite precursor solution and spin-coat it onto the surface of the NiOx / 5-fluoro-2-aminothiazole (IPA) film obtained in S3. The spin-coating process is 600 rpm for 10 s, followed by 300 rpm for 30 s. After heating the film at 100 °C for 10 minutes, it is placed at room temperature to obtain a perovskite (PVK) film with 5-fluoro-2-aminothiazole modified perovskite underside.

[0032] Meanwhile, perovskite films were obtained as a reference group using the same process, with NiOx substrates not treated with 5-fluoro-2-aminothiazole (IPA) / PVK and NiOx / PVK films as a control. After treating the NiOx / 5-fluoro-2-aminothiazole (IPA) / PVK and NiOx / PVK films, the PVK film was peeled off from the NiOx / 5-fluoro-2-aminothiazole (IPA) and NiOx surfaces, respectively. The morphology of the PVK underside surface was obtained by scanning electron microscopy, as shown below. Figure 1 As shown, compared with the reference group, the white bright spots on the lower surface of the perovskite film treated with 5-fluoro-2-aminothiazole (IPA) were significantly reduced. Based on the literature X. Yang, D. Luo, Y. Xiang, et al., Buried Interfaces in Halide Perovskite Photovoltaics [J]. Advanced Materials. 2021, 33, 2006435, the white bright spots are PbI2, because the defects on the lower surface of the PVK film treated with 5-fluoro-2-aminothiazole (IPA) were significantly reduced compared to the reference group. Figure 2 As shown, the NiOx / CBL(DMF) / PVK film exhibits stronger UV absorption, indicating that 5-fluoro-2-aminothiazole can significantly enhance the quality of perovskite films. Example 2

[0033] S1: Weigh PbI2 (426.4 mg), CsI (52 mg), PbBr2 (27.5 mg), and FAI (137.6 mg). Use a 3:1 (v / v) mixed solution of DMF and DMSO as solvent. Heat at 60°C for 2 hours and then cool to room temperature to prepare a perovskite precursor solution, which is FAI. 0.2 Cs 0.8 Pb(I 0.95 Br 0.05 3. Take CBL (3mg) and add it to 1ml of perovskite precursor solution. Then, heat at 60℃ for 10 minutes and let it cool to room temperature for later use.

[0034] S2: Use deionized water, acetone, ethanol and isopropanol to ultrasonically clean the ITO in sequence, each cleaning time is 10 minutes. Then, treat the dried ITO with plasma equipment for 6 minutes and take it out for use.

[0035] S3: Spin-coat the NiOx solution onto the ITO surface obtained in S2 at 600 rpm for 30 s. Then, heat the NiOx-covered ITO at 100°C for 10 minutes and then let it cool to room temperature for later use.

[0036] S4: Spin-coat the 5-fluoro-2-aminothiazole-doped perovskite precursor solution obtained in S1 onto the surface of the NiOx film obtained in S3. The spin-coating process is 600 rpm for 10 s, followed by 300 rpm for 30 s. The film is then heated at 100 °C for 10 minutes and then placed at room temperature to obtain the 5-fluoro-2-aminothiazole-doped perovskite film.

[0037] Undoped 5-fluoro-2-aminothiazole perovskite films were obtained using the same process. Scanning electron microscopy analysis showed that, as Figure 3 As shown, the grain size of the doped PVK film is increased, indicating a reduction in grain boundaries and defect states. Meanwhile, as... Figure 4 As shown, XRD results indicate that the film quality was significantly enhanced after doping with 5-fluoro-2-aminothiazole, and no new signal peaks appeared, indicating that 5-fluoro-2-aminothiazole did not participate in the perovskite crystallization process. Figure 5 As shown, the shift in the XPS signal indicates the binding of carboxyl functional groups in the dopant to lead ions at defect sites in the perovskite film; furthermore, as Figure 6 As shown, the perovskite film doped with 5-fluoro-2-aminothiazole exhibits higher PL intensity, indicating that the nonradiative recombination rate is reduced, effectively enhancing carrier transport. Example 3

[0038] Surface treatment with 5-fluoro-2-aminothiazole (IPA) and doping with 5-fluoro-2-aminothiazole together improve the surface quality of perovskite thin films. S1: The ITO was ultrasonically cleaned sequentially with deionized water, acetone, ethanol and isopropanol for 10 minutes each time. After that, the dried ITO was treated with plasma equipment for 6 minutes and then taken out for use. NiOx solution was spin-coated onto the ITO surface at 600 rpm for 30 seconds. Then, the NiOx-covered ITO was heated at 100°C for 10 minutes and then placed at room temperature for use.

[0039] S2: Weigh PbI+ (426.4 mg), CsI (52 mg), PbBr+ (27.5 mg), and FAI (137.6 mg). Use a 3:1 (v / v) mixed solution of DMF and DMSO as solvent. Heat at 60°C for 2 hours and then cool to room temperature to prepare a perovskite precursor solution, which is FAI. 0.2 Cs 0.8 Pb(I 0.95 Br 0.05 3. Take CBL (3mg) and add it to 1ml of perovskite precursor solution. Then, heat at 60℃ for 10 minutes and let it stand at room temperature for later use.

[0040] S3: Using IPA as a solvent, prepare a 0.3 mg / ml 5-fluoro-2-aminothiazole / IPA solution. Take 50 μL of the 0.3 mg / ml 5-fluoro-2-aminothiazole / IPA solution and spin-coat it onto the surface of the NiOx film to obtain a NiOx / 5-fluoro-2-aminothiazole (IPA) substrate for later use.

[0041] S4: The 5-fluoro-2-aminothiazole-doped perovskite precursor solution obtained in S2 was deposited on the surface of the NiOx / 5-fluoro-2-aminothiazole (IPA) substrate obtained in S3 by spin coating at 600 rpm for 10 s, followed by 300 rpm for 30 s. The film was heated at 100°C for 10 minutes and then cooled to room temperature to obtain a perovskite film with both the upper and lower surfaces treated with 5-fluoro-2-aminothiazole. PL test results show that, compared to the results of Examples 1 and 2, as... Figure 7 As shown, when CBL is used to treat both the upper and lower surfaces of the perovskite, the PL intensity is lower, indicating that this strategy is more effective in reducing the defect states of the perovskite and is more conducive to the efficient transport of charge carriers.

[0042] As a preferred technical solution, the surface encapsulation and interface strengthening process of the perovskite thin film includes the following steps performed in sequence: S401: UV-assisted surface activation and defect passivation The annealed perovskite film was placed in a sealed microenvironment chamber, which was equipped with a quartz observation window, a nitrogen inlet and a fiber optic humidity sensor. The chamber was maintained at a dry nitrogen positive pressure of 0.05-0.15 MPa, a relative humidity of ≤30% and a temperature of 25-30℃. The perovskite thin film surface is irradiated with a pulsed ultraviolet LED array with a wavelength of 360-370 nm (preferably 365 nm), a pulse duty cycle of 40%-60%, a frequency of 0.5-2 kHz, a power density of 50-80 mW / cm², and an irradiation time of 15-30 min. A quartz homogenizer (haze ≥80%) is set in the irradiation path to ensure that the irradiation uniformity deviation is <±5%, and the surface temperature of the thin film is controlled to ≤35℃ by a water-cooled base. The ultraviolet light irradiation promotes the interaction of the carboxyl functional group of 5-fluoro-2-aminothiazole with Pb on the perovskite surface. 2+ Defect sites form coordination bonds, while fluorine atoms are partially activated from the molecular backbone to the surface enriched state, constructing a fluorination-coordination synergistic passivation layer, reducing the surface defect state density to 5 × 10⁻⁶. 15 cm -3 the following.

[0043] S402: Interface Coupling Layer Construction An aminosilane coupling agent monolayer was prepared on the surface of a UV-activated perovskite film by spin coating: an isopropanol solution with an aminosilane coupling agent concentration of 1-3 wt% was prepared, wherein the aminosilane coupling agent was a mixture of γ-aminopropyltriethoxysilane (APTES) and γ-glycidoxypropyltrimethoxysilane (GPTMS) in a mass ratio of 1:0.5-1:1; The spin coating parameters are 2000-4000 rpm, 20-40 s, and film thickness controlled at 5-10 nm. Subsequently, the film is hot-pressed and cured at 80-100℃ and 0.05-0.2 MPa for 1-3 h, which causes the silanol groups to condense and form a Si-O-Si covalent network. At the same time, the amino group forms hydrogen bonds or amide covalent bonds with the carboxyl group of 5-fluoro-2-aminothiazole, constructing a three-level interface connection structure of "coordination bond-hydrogen bond-covalent bond", and the interfacial shear strength is increased to >5 MPa.

[0044] S403: Gradient SiO2 protective layer deposition A gradient SiO2 protective layer was deposited using plasma-enhanced chemical vapor deposition (PECVD). Prior to deposition, the substrate was subjected to Ar oxidation. + Plasma pre-cleaning (power 20-40W, bias voltage -30 to -60 V, time 3-5 min) is used to remove surface adsorbates and increase surface roughness. During deposition, a planetary rotating jig or back-side heating of the substrate is used to ensure temperature uniformity of ±3℃; the gradient SiO2 protective layer includes: Inner dense barrier layer (adjacent to the perovskite interface): 20-30 nm thick, density >2.2 g / cm³, used to block water vapor, oxygen atoms and high-energy particles from erosion, and protect the carboxyl functional groups of the interface from oxidation failure. Outer stress buffer layer: 60-90 nm thick, 5%-15% porosity, Young's modulus reduced by 30%-50% compared to the inner layer, used to release shear stress generated by space thermal cycling (-150℃~+120℃); Deposition process parameters: temperature 80-120℃, time 15-25 min, total thickness 80-120 nm, film thickness non-uniformity <5%.

[0045] S404: Post-processing and Performance Optimization After deposition, the film was annealed at 60-80℃ in a vacuum environment (<10 Pa) for 10-15 min to eliminate residual compressive stress in the SiO2 film; the resulting gradient encapsulation structure enables the perovskite film to withstand extreme space environments (vacuum degree ≤10 Pa). -5The photoelectric performance retention rate under (Pa, ultraviolet irradiation, proton irradiation and thermal cycling) is 5%-8% higher than that of the unencapsulated sample, and after 200 cycles of -80℃↔+80℃ thermal cycling, the interfacial shear strength retention rate is >90%, with no delamination or peeling.

[0046] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for improving the quality of perovskite thin films through the dual application of 5-fluoro-2-aminothiazole, characterized in that, Includes the following steps: A NiOx / 5-fluoro-2-aminothiazole (IPA) film was obtained by spin-coating an IPA solution containing 5-fluoro-2-aminothiazole onto the surface of a NiOx film. In addition, 5-fluoro-2-aminothiazole was doped into the perovskite precursor solution and deposited on the surface of the NiOx / 5-fluoro-2-aminothiazole (IPA) film to form a perovskite film on the passivation layer. Annealing forms a perovskite thin film with excellent environmental stability, making it suitable for high-radiation, high-temperature-difference, and high-vacuum environments in space.

2. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 1, characterized in that: In IPA solutions containing 5-fluoro-2-aminothiazole, the concentration of 5-fluoro-2-aminothiazole is 0.5-1 mg / ml.

3. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 1, characterized in that: In the step of doping 5-fluoro-2-aminothiazole into the perovskite precursor solution, the concentration of 5-fluoro-2-aminothiazole is 0.3 mg / ml.

4. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 1, characterized in that: The perovskite precursor solution is FA. 1-x CsxPbIyBr 3-y (0≤x≤1, 0≤y≤3), the preparation process is as follows: weigh several of PbI2, CsI, PbBr2 and FAI, and use a mixed solution of DMF and DMSO with a volume ratio of 3:1 as a solvent for preparation.

5. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 1, characterized in that: The perovskite thin film material has an ABX3 structure, where the A site is one or both of formidium ions and cesium ions, the B site is a lead ion, and the X site is one of chloride ions, bromide ions, and iodide ions, or X is a mixture of multiple ABX3 ions under different ion conditions.

6. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 1, characterized in that: In the step of doping 5-fluoro-2-aminothiazole into the perovskite precursor solution, the solution is heated at 60-80°C for 10-15 minutes and then cooled to room temperature for later use.

7. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 1, characterized in that: The annealing process involves treating the film at 100–150°C for 10–15 minutes, and the resulting film maintains its structural integrity and high performance under thermal cycling and radiation conditions.

8. The method for improving the quality of perovskite thin films through the dual application of 5-fluoro-2-aminothiazole according to claim 1, characterized in that, It also includes the following steps: A gradient SiO2 protective layer was deposited on the surface of the annealed perovskite film using plasma-enhanced chemical vapor deposition (PECVD). The gradient SiO2 protective layer comprises: a dense barrier layer adjacent to the perovskite film, with a thickness of 20-30 nm, used to block moisture and particle erosion; and a stress buffer layer above the dense barrier layer, with a thickness of 60-90 nm and a porosity controlled at 5%-15%, used to release thermal cycling stress. The deposition temperature was controlled at 80-100℃, the deposition time was 15-25 min, and the total thickness was 80-120 nm. Before deposition, the perovskite film surface was pre-cleaned with Ar⁺ plasma at a power of 20-40 W, a bias voltage of -30 to -60 V, and a time of 3-5 min to remove surface adsorbates and increase surface roughness. During deposition, a planetary rotating fixture or back-side heating of the substrate was used to ensure that the substrate temperature uniformity was controlled within ±3℃ and the film thickness non-uniformity was <5%.

9. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 8, characterized in that, Before depositing the gradient SiO2 protective layer, an ultraviolet light-assisted passivation step is included: the annealed perovskite film is placed in a sealed microenvironment chamber, which is filled with dry nitrogen and maintained at a positive pressure of 0.05-0.15 MPa, relative humidity ≤30%, and temperature of 25-30℃; the surface of the perovskite film is irradiated with a pulsed ultraviolet LED array with a wavelength of 365nm, a pulse duty cycle of 40%-60%, a frequency of 0.5-2kHz, an irradiation power density of 50-80 mW / cm², and an irradiation time of 20-30min; during the irradiation process, a quartz light homogenizer is used to ensure that the irradiation uniformity deviation is <±5%, and the surface temperature of the perovskite film is controlled not to exceed 35℃ by a water-cooled base; the ultraviolet light irradiation is used to promote the coordination binding efficiency of the carboxyl functional group of 5-fluoro-2-aminothiazole with the perovskite defect sites, and at the same time activate the synergistic enhancement effect of fluorine atoms and thiazole rings.

10. The method for improving the quality of perovskite thin films by dual application of 5-fluoro-2-aminothiazole according to claim 9, characterized in that, The SiO2 protective layer is doped with 0.5-1 wt% of an aminosilane coupling agent. The amino group of the aminosilane coupling agent can form hydrogen bonds with the carboxyl group of 5-fluoro-2-aminothiazole, which further enhances the bonding force between the SiO2 protective layer and the perovskite film. At the same time, it helps the carboxyl functional group to be fixed at the defect site, avoiding the breakage of the coordination bond.

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